RE: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments)
Well... Canons don't always get what you exåect. I danish guy wrote this at Photo.net: Can anybody help. I have just been to Miami to shoot for a danish magazine and around all my photos (90%) is out of focus ? i use a EOS 1Ds camara and with EF 24-70 L USM - EF 100 USM macro and a 70-200 L USM IS lenses. I never used a tripod and around 250 shutter speed all time and also from bl. 4 to 5.6 mostly because i shoot fashion. I dont understand why most of all my photos is blurered i tough Canon lenses was the best and fastest auto focus on the market. I even tryed single AF point in the middle and also the auto AF point 45 both ways i never got some really sharp pictures. I remember in the old days with film a Canon EOS 5 or Nikon 5 all pictures was focused is there any special rules for Digital i mean, shutter speed and Bl. is same thing right Shutter speed 250 must be shutter speed 250 on both camaras or do you always need a faster shutter speed with digital ? please i need help fast ! kind regard Mugge T answer his question: Yes, there's is a difference. Due to the grater enlargement (crop factor) the shutter speed necessary to freeze movent must be divided by the crop factor: If i.e. a 250mm is used: 1/250 divided by i.e. 1.5 = 1/375 sec. 90% out of focus! That bad! Cheers Jens Bladt mailto:[EMAIL PROTECTED] http://hjem.get2net.dk/bladt
Re: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments)
On 17/1/05, Jens Bladt, discombobulated, unleashed: Well... Canons don't always get what you exåect. I danish guy wrote this at Photo.net: Can anybody help. I have just been to Miami to shoot for a danish magazine and around all my photos (90%) is out of focus ? i use a EOS 1Ds camara and with EF 24-70 L USM - EF 100 USM macro and a 70-200 L USM IS lenses. I never used a tripod and around 250 shutter speed all time and also from bl. 4 to 5.6 mostly because i shoot fashion. I dont understand why most of all my photos is blurered i tough Canon lenses was the best and fastest auto focus on the market. I even tryed single AF point in the middle and also the auto AF point 45 both ways i never got some really sharp pictures. I remember in the old days with film a Canon EOS 5 or Nikon 5 all pictures was focused is there any special rules for Digital i mean, shutter speed and Bl. is same thing right Shutter speed 250 must be shutter speed 250 on both camaras or do you always need a faster shutter speed with digital ? please i need help fast ! kind regard Mugge T answer his question: Yes, there's is a difference. Due to the grater enlargement (crop factor) the shutter speed necessary to freeze movent must be divided by the crop factor: If i.e. a 250mm is used: 1/250 divided by i.e. 1.5 = 1/375 sec. 90% out of focus! That bad! Sorry Jens, the only thing this proves to me is that the operator didn't put enough time/resources into understanding how to operate the gear properly. The fact he's posting to Photo.net illustrates lack of resourcefulness to me. It's a bit like me writing to Cow.net and saying that I bought a cow, put a bucket under the cow and squeezed the teats, but nothing happened. What am I doing wrong? (Answer, of course, is get the cow pregnant first ;-) The point I am making is that just because someone says something doesn't work properly, does not mean that it is not working properly. Ever heard the expression 'a poor workman always blames his tools' ? Cheers, Cotty ___/\__ || (O) | People, Places, Pastiche ||=|http://www.cottysnaps.com _
Re: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments)
On 17/1/05, Cotty, discombobulated, unleashed: T answer his question: Yes, there's is a difference. Due to the grater enlargement (crop factor) the shutter speed necessary to freeze movent must be divided by the crop factor: If i.e. a 250mm is used: 1/250 divided by i.e. 1.5 = 1/375 sec. 90% out of focus! That bad! I mean for crying out loud, it's a 1Ds - there *is no crop factor* involved - it's a full frame camera. What planet do these people come from ? Cheers, Cotty ___/\__ || (O) | People, Places, Pastiche ||=|http://www.cottysnaps.com _
Re: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments)
Cotty [EMAIL PROTECTED] wrote: On 17/1/05, Cotty, discombobulated, unleashed: T answer his question: Yes, there's is a difference. Due to the grater enlargement (crop factor) the shutter speed necessary to freeze movent must be divided by the crop factor: If i.e. a 250mm is used: 1/250 divided by i.e. 1.5 = 1/375 sec. 90% out of focus! That bad! I mean for crying out loud, it's a 1Ds - there *is no crop factor* involved - it's a full frame camera. What planet do these people come from ? Well cut the fellow a little slack, Cotty. Perhaps he just isn't too bright. After all, he *is* a Canon user. ;-) -- Mark Roberts Photography and writing www.robertstech.com
Re: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments)
On Mon, 17 Jan 2005, Cotty wrote: Well cut the fellow a little slack, Cotty. Perhaps he just isn't too bright. After all, he *is* a Canon user. ;-) ARGHH Point taken LOL I thought Jens shoots Pentax! ;-))) Kostas
Re: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments)
I thought Jens shoots Pentax! ;-))) better shoot with Pentax than being shot by Canon ;-) Bedo.
Re: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments)
On 17/1/05, Mark Roberts, discombobulated, unleashed: Cotty [EMAIL PROTECTED] wrote: On 17/1/05, Cotty, discombobulated, unleashed: T answer his question: Yes, there's is a difference. Due to the grater enlargement (crop factor) the shutter speed necessary to freeze movent must be divided by the crop factor: If i.e. a 250mm is used: 1/250 divided by i.e. 1.5 = 1/375 sec. 90% out of focus! That bad! I mean for crying out loud, it's a 1Ds - there *is no crop factor* involved - it's a full frame camera. What planet do these people come from ? Well cut the fellow a little slack, Cotty. Perhaps he just isn't too bright. After all, he *is* a Canon user. ;-) ARGHH Point taken LOL Cheers, Cotty ___/\__ || (O) | People, Places, Pastiche ||=|http://www.cottysnaps.com _
Re: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments)
- Original Message - From: Cotty Subject: Re: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments) I mean for crying out loud, it's a 1Ds - there *is no crop factor* involved - it's a full frame camera. What planet do these people come from ? Uranus. Or if not ur's, somebody's. This allows me to bring up my pet peeve of the past couple of decades, which is: The cameras are taking on so much of the technical side of photography, freeing up the photographer to do what? Well, it seems often, it is freeing up the photographer to be stupid, not know his theory, and hence screw up on the practical side of things, which is the taking of photographs. Sadly, this doltishness is not limited to snapshooters with point and shoots. Often, the pro boys are not much better. William Robb
Re: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments)
Q. To be a successful professional photographer, what 3 things do you most need to know about photography? A. 1. Marketing, 2. Marketing, 3. Marketing. graywolf http://www.graywolfphoto.com Idiot Proof == Expert Proof --- William Robb wrote: - Original Message - From: Cotty Subject: Re: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments) I mean for crying out loud, it's a 1Ds - there *is no crop factor* involved - it's a full frame camera. What planet do these people come from ? Uranus. Or if not ur's, somebody's. This allows me to bring up my pet peeve of the past couple of decades, which is: The cameras are taking on so much of the technical side of photography, freeing up the photographer to do what? Well, it seems often, it is freeing up the photographer to be stupid, not know his theory, and hence screw up on the practical side of things, which is the taking of photographs. Sadly, this doltishness is not limited to snapshooters with point and shoots. Often, the pro boys are not much better. William Robb -- No virus found in this outgoing message. Checked by AVG Anti-Virus. Version: 7.0.300 / Virus Database: 265.6.13 - Release Date: 1/16/2005
Re: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments)
I guess 10-30mm off could be considered out of focus. The camera may have been foccusing at the nose, not the eyes! Jens Bladt mailto:[EMAIL PROTECTED] http://hjem.get2net.dk/bladt -Oprindelig meddelelse- Fra: Cotty [mailto:[EMAIL PROTECTED] Sendt: 17. januar 2005 14:44 Til: pentax list Emne: Re: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments) On 17/1/05, Mark Roberts, discombobulated, unleashed: Cotty [EMAIL PROTECTED] wrote: On 17/1/05, Cotty, discombobulated, unleashed: T answer his question: Yes, there's is a difference. Due to the grater enlargement (crop factor) the shutter speed necessary to freeze movent must be divided by the crop factor: If i.e. a 250mm is used: 1/250 divided by i.e. 1.5 = 1/375 sec. 90% out of focus! That bad! I mean for crying out loud, it's a 1Ds - there *is no crop factor* involved - it's a full frame camera. What planet do these people come from ? Well cut the fellow a little slack, Cotty. Perhaps he just isn't too bright. After all, he *is* a Canon user. ;-) ARGHH Point taken LOL Cheers, Cotty ___/\__ || (O) | People, Places, Pastiche ||=|http://www.cottysnaps.com _
RE: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments)
I agree, Cotty. He probably had the camera choose the wrong focus points most of the time. Furthermore 1/250 sec. is perhaps a bit on the slow side. Jens Bladt mailto:[EMAIL PROTECTED] http://hjem.get2net.dk/bladt -Oprindelig meddelelse- Fra: Cotty [mailto:[EMAIL PROTECTED] Sendt: 17. januar 2005 10:24 Til: pentax list Emne: Re: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments) On 17/1/05, Jens Bladt, discombobulated, unleashed: Well... Canons don't always get what you exåect. I danish guy wrote this at Photo.net: Can anybody help. I have just been to Miami to shoot for a danish magazine and around all my photos (90%) is out of focus ? i use a EOS 1Ds camara and with EF 24-70 L USM - EF 100 USM macro and a 70-200 L USM IS lenses. I never used a tripod and around 250 shutter speed all time and also from bl. 4 to 5.6 mostly because i shoot fashion. I dont understand why most of all my photos is blurered i tough Canon lenses was the best and fastest auto focus on the market. I even tryed single AF point in the middle and also the auto AF point 45 both ways i never got some really sharp pictures. I remember in the old days with film a Canon EOS 5 or Nikon 5 all pictures was focused is there any special rules for Digital i mean, shutter speed and Bl. is same thing right Shutter speed 250 must be shutter speed 250 on both camaras or do you always need a faster shutter speed with digital ? please i need help fast ! kind regard Mugge T answer his question: Yes, there's is a difference. Due to the grater enlargement (crop factor) the shutter speed necessary to freeze movent must be divided by the crop factor: If i.e. a 250mm is used: 1/250 divided by i.e. 1.5 = 1/375 sec. 90% out of focus! That bad! Sorry Jens, the only thing this proves to me is that the operator didn't put enough time/resources into understanding how to operate the gear properly. The fact he's posting to Photo.net illustrates lack of resourcefulness to me. It's a bit like me writing to Cow.net and saying that I bought a cow, put a bucket under the cow and squeezed the teats, but nothing happened. What am I doing wrong? (Answer, of course, is get the cow pregnant first ;-) The point I am making is that just because someone says something doesn't work properly, does not mean that it is not working properly. Ever heard the expression 'a poor workman always blames his tools' ? Cheers, Cotty ___/\__ || (O) | People, Places, Pastiche ||=|http://www.cottysnaps.com _
RE: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments)
I don't know the 1Ds. But, I believe 95% of all digies are less than full frame. Jens Bladt mailto:[EMAIL PROTECTED] http://hjem.get2net.dk/bladt -Oprindelig meddelelse- Fra: Cotty [mailto:[EMAIL PROTECTED] Sendt: 17. januar 2005 12:48 Til: pentax list Emne: Re: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments) On 17/1/05, Cotty, discombobulated, unleashed: T answer his question: Yes, there's is a difference. Due to the grater enlargement (crop factor) the shutter speed necessary to freeze movent must be divided by the crop factor: If i.e. a 250mm is used: 1/250 divided by i.e. 1.5 = 1/375 sec. 90% out of focus! That bad! I mean for crying out loud, it's a 1Ds - there *is no crop factor* involved - it's a full frame camera. What planet do these people come from ? Cheers, Cotty ___/\__ || (O) | People, Places, Pastiche ||=|http://www.cottysnaps.com _
Re: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments)
the 1Ds does lock on a subject and track its motion provided that it stays under any one of the focus points. it will track a moving bird or football player provided that you aim the camera roughly aimed correctly. no Pentax camera does this well enough to really useful, but the Canon 1D system does. Herb... - Original Message - From: Jens Bladt [EMAIL PROTECTED] To: pentax-discuss@pdml.net Sent: Monday, January 17, 2005 2:01 AM Subject: RE: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments) I agree. But my point was that there's no locking on to the subject. It's just the focus system catching whatever comes by, close to the previous focusing distance. If I was photographing a group of kids running at the playground, the camera might catch a girl, then a boy, next time a dog or a bird. There' s no locking onto anything. I don't believe any mass produced camera system can do that.
Re: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments)
Herb Chong wrote: the 1Ds does lock on a subject and track its motion provided that it stays under any one of the focus points. it will track a moving bird or football player provided that you aim the camera roughly aimed correctly. no Pentax camera does this well enough to really useful, but the Canon 1D system does. I'll second Herb's point. The 1D___'s seem to do this very well- the results even look more successful than what you're seeing in the viewfinder. -Ryan
Re: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments)
On 17/1/05, Jens Bladt, discombobulated, unleashed: I agree, Cotty. He probably had the camera choose the wrong focus points most of the time. Furthermore 1/250 sec. is perhaps a bit on the slow side. Yes but for what focal length? and at what ISO?? And what was the condition of the photographer? was he missing his morning line of coke?? There are so many variables. My favourite line from one of my favourite movies is the scene in The War Room in Kubrick's 'Dr. Strangelove' where General Buck Turgidson (played brilliantly by George C Scott) ushers caution to President Muffley (Peter Sellers) by saying: 'Well, I'd like to hold off judgment on a thing like that, sir, until all the facts are in.' I agree. Cheers, Cotty ___/\__ || (O) | People, Places, Pastiche ||=|http://www.cottysnaps.com _
RE: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments)
Didn't Contax make one too? Jens Bladt mailto:[EMAIL PROTECTED] http://hjem.get2net.dk/bladt -Oprindelig meddelelse- Fra: Peter J. Alling [mailto:[EMAIL PROTECTED] Sendt: 17. januar 2005 22:42 Til: pentax-discuss@pdml.net Emne: Re: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments) Just the Canon, and the Kodak semi twins, (c/n), are full frame as far as I can recall. Jens Bladt wrote: I don't know the 1Ds. But, I believe 95% of all digies are less than full frame. Jens Bladt mailto:[EMAIL PROTECTED] http://hjem.get2net.dk/bladt -Oprindelig meddelelse- Fra: Cotty [mailto:[EMAIL PROTECTED] Sendt: 17. januar 2005 12:48 Til: pentax list Emne: Re: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments) On 17/1/05, Cotty, discombobulated, unleashed: T answer his question: Yes, there's is a difference. Due to the grater enlargement (crop factor) the shutter speed necessary to freeze movent must be divided by the crop factor: If i.e. a 250mm is used: 1/250 divided by i.e. 1.5 = 1/375 sec. 90% out of focus! That bad! I mean for crying out loud, it's a 1Ds - there *is no crop factor* involved - it's a full frame camera. What planet do these people come from ? Cheers, Cotty ___/\__ || (O) | People, Places, Pastiche ||=|http://www.cottysnaps.com _ -- I can understand why mankind hasn't given up war. During a war you get to drive tanks through the sides of buildings and shoot foreigners - two things that are usually frowned on during peacetime. --P.J. O'Rourke
Re: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments)
If we knew, could we send them back? Cotty wrote: On 17/1/05, Cotty, discombobulated, unleashed: T answer his question: Yes, there's is a difference. Due to the grater enlargement (crop factor) the shutter speed necessary to freeze movent must be divided by the crop factor: If i.e. a 250mm is used: 1/250 divided by i.e. 1.5 = 1/375 sec. 90% out of focus! That bad! I mean for crying out loud, it's a 1Ds - there *is no crop factor* involved - it's a full frame camera. What planet do these people come from ? Cheers, Cotty ___/\__ || (O) | People, Places, Pastiche ||=|http://www.cottysnaps.com _ -- I can understand why mankind hasn't given up war. During a war you get to drive tanks through the sides of buildings and shoot foreigners - two things that are usually frowned on during peacetime. --P.J. O'Rourke
Re: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments)
Just the Canon, and the Kodak semi twins, (c/n), are full frame as far as I can recall. Jens Bladt wrote: I don't know the 1Ds. But, I believe 95% of all digies are less than full frame. Jens Bladt mailto:[EMAIL PROTECTED] http://hjem.get2net.dk/bladt -Oprindelig meddelelse- Fra: Cotty [mailto:[EMAIL PROTECTED] Sendt: 17. januar 2005 12:48 Til: pentax list Emne: Re: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments) On 17/1/05, Cotty, discombobulated, unleashed: T answer his question: Yes, there's is a difference. Due to the grater enlargement (crop factor) the shutter speed necessary to freeze movent must be divided by the crop factor: If i.e. a 250mm is used: 1/250 divided by i.e. 1.5 = 1/375 sec. 90% out of focus! That bad! I mean for crying out loud, it's a 1Ds - there *is no crop factor* involved - it's a full frame camera. What planet do these people come from ? Cheers, Cotty ___/\__ || (O) | People, Places, Pastiche ||=|http://www.cottysnaps.com _ -- I can understand why mankind hasn't given up war. During a war you get to drive tanks through the sides of buildings and shoot foreigners - two things that are usually frowned on during peacetime. --P.J. O'Rourke
Re: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments)
Oooh, good one! Mark Roberts wrote: Cotty [EMAIL PROTECTED] wrote: On 17/1/05, Cotty, discombobulated, unleashed: T answer his question: Yes, there's is a difference. Due to the grater enlargement (crop factor) the shutter speed necessary to freeze movent must be divided by the crop factor: If i.e. a 250mm is used: 1/250 divided by i.e. 1.5 = 1/375 sec. 90% out of focus! That bad! I mean for crying out loud, it's a 1Ds - there *is no crop factor* involved - it's a full frame camera. What planet do these people come from ? Well cut the fellow a little slack, Cotty. Perhaps he just isn't too bright. After all, he *is* a Canon user. ;-) -- I can understand why mankind hasn't given up war. During a war you get to drive tanks through the sides of buildings and shoot foreigners - two things that are usually frowned on during peacetime. --P.J. O'Rourke
Re: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments)
You're right and a good example of why Pentax abandoned marketing the MZ-D or whatever it would have been called. Jens Bladt wrote: Didn't Contax make one too? Jens Bladt mailto:[EMAIL PROTECTED] http://hjem.get2net.dk/bladt -Oprindelig meddelelse- Fra: Peter J. Alling [mailto:[EMAIL PROTECTED] Sendt: 17. januar 2005 22:42 Til: pentax-discuss@pdml.net Emne: Re: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments) Just the Canon, and the Kodak semi twins, (c/n), are full frame as far as I can recall. Jens Bladt wrote: I don't know the 1Ds. But, I believe 95% of all digies are less than full frame. Jens Bladt mailto:[EMAIL PROTECTED] http://hjem.get2net.dk/bladt -Oprindelig meddelelse- Fra: Cotty [mailto:[EMAIL PROTECTED] Sendt: 17. januar 2005 12:48 Til: pentax list Emne: Re: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments) On 17/1/05, Cotty, discombobulated, unleashed: T answer his question: Yes, there's is a difference. Due to the grater enlargement (crop factor) the shutter speed necessary to freeze movent must be divided by the crop factor: If i.e. a 250mm is used: 1/250 divided by i.e. 1.5 = 1/375 sec. 90% out of focus! That bad! I mean for crying out loud, it's a 1Ds - there *is no crop factor* involved - it's a full frame camera. What planet do these people come from ? Cheers, Cotty ___/\__ || (O) | People, Places, Pastiche ||=|http://www.cottysnaps.com _ -- I can understand why mankind hasn't given up war. During a war you get to drive tanks through the sides of buildings and shoot foreigners - two things that are usually frowned on during peacetime. --P.J. O'Rourke -- I can understand why mankind hasn't given up war. During a war you get to drive tanks through the sides of buildings and shoot foreigners - two things that are usually frowned on during peacetime. --P.J. O'Rourke
RE: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments)
Full Frame: Kodak can, Canon can, Nikon can, Contax just about did it, Pentax nearly could! Ths makes Pentax a winner! I see. Thank you. Jens Bladt mailto:[EMAIL PROTECTED] http://hjem.get2net.dk/bladt -Oprindelig meddelelse- Fra: Peter J. Alling [mailto:[EMAIL PROTECTED] Sendt: 18. januar 2005 02:46 Til: pentax-discuss@pdml.net Emne: Re: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments) You're right and a good example of why Pentax abandoned marketing the MZ-D or whatever it would have been called. Jens Bladt wrote: Didn't Contax make one too? Jens Bladt mailto:[EMAIL PROTECTED] http://hjem.get2net.dk/bladt -Oprindelig meddelelse- Fra: Peter J. Alling [mailto:[EMAIL PROTECTED] Sendt: 17. januar 2005 22:42 Til: pentax-discuss@pdml.net Emne: Re: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments) Just the Canon, and the Kodak semi twins, (c/n), are full frame as far as I can recall. Jens Bladt wrote: I don't know the 1Ds. But, I believe 95% of all digies are less than full frame. Jens Bladt mailto:[EMAIL PROTECTED] http://hjem.get2net.dk/bladt -Oprindelig meddelelse- Fra: Cotty [mailto:[EMAIL PROTECTED] Sendt: 17. januar 2005 12:48 Til: pentax list Emne: Re: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments) On 17/1/05, Cotty, discombobulated, unleashed: T answer his question: Yes, there's is a difference. Due to the grater enlargement (crop factor) the shutter speed necessary to freeze movent must be divided by the crop factor: If i.e. a 250mm is used: 1/250 divided by i.e. 1.5 = 1/375 sec. 90% out of focus! That bad! I mean for crying out loud, it's a 1Ds - there *is no crop factor* involved - it's a full frame camera. What planet do these people come from ? Cheers, Cotty ___/\__ || (O) | People, Places, Pastiche ||=|http://www.cottysnaps.com _ -- I can understand why mankind hasn't given up war. During a war you get to drive tanks through the sides of buildings and shoot foreigners - two things that are usually frowned on during peacetime. --P.J. O'Rourke -- I can understand why mankind hasn't given up war. During a war you get to drive tanks through the sides of buildings and shoot foreigners - two things that are usually frowned on during peacetime. --P.J. O'Rourke
RE: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments)
Yes. ...what they all will say, in order to sell. Don't believe everything you read in an ad! I guess tracking describes the currently available AF functions better than locking. What they mean by locking is simply focus or obtain focus confirmation. But focus confirmation just indicates that something is in focus. Tracking might be close to what Minolta called predictable auto focus when the Dynaxes were introduced. The camera can predict a (single) subjects movement across the screen to determine the place where it will be, at the real time of the release. Since the introduction of multiple focus points, I haven't seen predictable AF in the ads anymore. Pentax PZ-1 had a similar description (predictable AF in Continuous mode) in its user manual. Today this is just called continuous focus C. C jsut means the camera will try to refocus whenever the subject gets out of focus. It will then perhaps focus onsomthning else - perhaps the next guy in a line. I don't know they (C) can actually predict anything anymore. In my world (Pentax) there's just Single and Continuous. And then there's the automatic selection of focusing point. This simply means multiple sigle or multiple continuous. These features will allow the camera to focus on just about anything. I suppose that's quite the opposite of locking on to a (single) subject. I'd love to be around on the day they invent a camera you can point at the centre forward at the beginning of a soccer game, give you focus confirmation and then stay focused on the guy for the rest of that half. I suppose true locking will require some kind of 3D focusing system combined with computerized optical recognition. Jens Bladt mailto:[EMAIL PROTECTED] http://hjem.get2net.dk/bladt -Oprindelig meddelelse- Fra: Herb Chong [mailto:[EMAIL PROTECTED] Sendt: 16. januar 2005 00:53 Til: pentax-discuss@pdml.net Emne: Re: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments) tracking and locking are the same thing in most manufacturer's literature. Herb - Original Message - From: Jens Bladt [EMAIL PROTECTED] To: pentax-discuss@pdml.net Sent: Saturday, January 15, 2005 6:43 PM Subject: RE: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments) About locking onto something: To me this means focusing on a subject, then stay focused at the same subject, even if it moves. No camera that I know of does this. Not even the Canon D1. Cameras loose focus when things move, but may refocus at the same subject after a while. Or it may focus on something else! That's not locking onto a subject, is it? Tracking perhaps, but certainly not locking.
RE: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments)
I'd love to be around on the day they invent a camera you can point at the centre forward at the beginning of a soccer game, give you focus confirmation and then stay focused on the guy for the rest of that half. I suppose true locking will require some kind of 3D focusing system combined with computerized optical recognition. I guess it would be even better if the camera could just stay focused on the ball! :-) Jens mailto:[EMAIL PROTECTED] http://hjem.get2net.dk/bladt -Oprindelig meddelelse- Fra: Jens Bladt [mailto:[EMAIL PROTECTED] Sendt: 16. januar 2005 09:21 Til: pentax-discuss@pdml.net Emne: RE: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments) Yes. ...what they all will say, in order to sell. Don't believe everything you read in an ad! I guess tracking describes the currently available AF functions better than locking. What they mean by locking is simply focus or obtain focus confirmation. But focus confirmation just indicates that something is in focus. Tracking might be close to what Minolta called predictable auto focus when the Dynaxes were introduced. The camera can predict a (single) subjects movement across the screen to determine the place where it will be, at the real time of the release. Since the introduction of multiple focus points, I haven't seen predictable AF in the ads anymore. Pentax PZ-1 had a similar description (predictable AF in Continuous mode) in its user manual. Today this is just called continuous focus C. C jsut means the camera will try to refocus whenever the subject gets out of focus. It will then perhaps focus onsomthning else - perhaps the next guy in a line. I don't know they (C) can actually predict anything anymore. In my world (Pentax) there's just Single and Continuous. And then there's the automatic selection of focusing point. This simply means multiple sigle or multiple continuous. These features will allow the camera to focus on just about anything. I suppose that's quite the opposite of locking on to a (single) subject. I'd love to be around on the day they invent a camera you can point at the centre forward at the beginning of a soccer game, give you focus confirmation and then stay focused on the guy for the rest of that half. I suppose true locking will require some kind of 3D focusing system combined with computerized optical recognition. Jens Bladt mailto:[EMAIL PROTECTED] http://hjem.get2net.dk/bladt -Oprindelig meddelelse- Fra: Herb Chong [mailto:[EMAIL PROTECTED] Sendt: 16. januar 2005 00:53 Til: pentax-discuss@pdml.net Emne: Re: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments) tracking and locking are the same thing in most manufacturer's literature. Herb - Original Message - From: Jens Bladt [EMAIL PROTECTED] To: pentax-discuss@pdml.net Sent: Saturday, January 15, 2005 6:43 PM Subject: RE: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments) About locking onto something: To me this means focusing on a subject, then stay focused at the same subject, even if it moves. No camera that I know of does this. Not even the Canon D1. Cameras loose focus when things move, but may refocus at the same subject after a while. Or it may focus on something else! That's not locking onto a subject, is it? Tracking perhaps, but certainly not locking.
Re: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments)
On 16/1/05, Jens Bladt, discombobulated, unleashed: I handled one of the very first five Canon D1's, when they first came to Europe (2001?) at a Canon presentation in Cork, Ireland. It had 45 focus points. The viewfinder was totally covered with focus points - they lit up like the neon lights of Las Vegas, when the camera was moved. The focus changed as fast as I could move the camera. And it took 4-8 frames every time I pressed the shutter (8 fps). It sounded like a freaking Uzi! The focus points can be set so that they do not light up, and can be set so that all or some or one are active. About locking onto something: To me this means focusing on a subject, then stay focused at the same subject, even if it moves. No camera that I know of does this. Not even the Canon D1. The 1D can do this no problem. It also has predictive focussing so that if a bird is flying towards you, it realises this and moves the focus to stay with it. I tend to use manual focus for most things, but I was shooting a soccer match the other day at a school (my son was playing) until I was spotted and told photography was not permitted on school grounds with written permission (shoot first ask questions later). Out of about a hundred frames, I noticed one was a bit soft on the subject (my son) - and that was because he darted behind another player and the camera got confused. I think the ideal focus system would be like that super-duper handheld weapon in 'The Fifth Element' that Zorg demonstrates to a horde of unruly aliens whereby when it is fired at the target, all subsequent firings hit the same target no matter where the weapon is pointed! http://www.geekroar.com/film/archives/5th_goldman.jpg :-) Cheers, Cotty ___/\__ || (O) | People, Places, Pastiche ||=|http://www.cottysnaps.com _
RE: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments)
I wouldn't be sure the D1 would focus/refocus at the same object every time! Jens Bladt mailto:[EMAIL PROTECTED] http://hjem.get2net.dk/bladt -Oprindelig meddelelse- Fra: Herb Chong [mailto:[EMAIL PROTECTED] Sendt: 16. januar 2005 14:22 Til: pentax-discuss@pdml.net Emne: Re: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments) this is the reason for my original comments. i know the 1D can do this. i've seen the photographic results. Herb - Original Message - From: Cotty [EMAIL PROTECTED] To: pentax list pentax-discuss@pdml.net Sent: Sunday, January 16, 2005 5:48 AM Subject: Re: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments) About locking onto something: To me this means focusing on a subject, then stay focused at the same subject, even if it moves. No camera that I know of does this. Not even the Canon D1. The 1D can do this no problem. It also has predictive focussing so that if a bird is flying towards you, it realises this and moves the focus to stay with it.
Re: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments)
this is the reason for my original comments. i know the 1D can do this. i've seen the photographic results. Herb - Original Message - From: Cotty [EMAIL PROTECTED] To: pentax list pentax-discuss@pdml.net Sent: Sunday, January 16, 2005 5:48 AM Subject: Re: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments) About locking onto something: To me this means focusing on a subject, then stay focused at the same subject, even if it moves. No camera that I know of does this. Not even the Canon D1. The 1D can do this no problem. It also has predictive focussing so that if a bird is flying towards you, it realises this and moves the focus to stay with it.
Re: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments)
every time isn't the issue. 90% is good enough to make not using it when available stupid. Herb... - Original Message - From: Jens Bladt [EMAIL PROTECTED] To: pentax-discuss@pdml.net Sent: Sunday, January 16, 2005 10:17 AM Subject: RE: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments) I wouldn't be sure the D1 would focus/refocus at the same object every time!
RE: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments)
I agree. But my point was that there's no locking on to the subject. It's just the focus system catching whatever comes by, close to the previous focusing distance. If I was photographing a group of kids running at the playground, the camera might catch a girl, then a boy, next time a dog or a bird. There s no locking onto anything. I don't believe any mass produced camera system can do that. I have tried to walk slowly towards a fixed subject with great contrast, having set the AF on the *ist D to Continuous. When walking quite slowly, the camera could give focus confirmation once for every single step I took. That's app. once every second or every half-second. That is certainly not very impressing. In fact I can do better using manual focus. Jens Bladt mailto:[EMAIL PROTECTED] http://hjem.get2net.dk/bladt -Oprindelig meddelelse- Fra: Herb Chong [mailto:[EMAIL PROTECTED] Sendt: 17. januar 2005 01:33 Til: pentax-discuss@pdml.net Emne: Re: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments) every time isn't the issue. 90% is good enough to make not using it when available stupid. Herb... - Original Message - From: Jens Bladt [EMAIL PROTECTED] To: pentax-discuss@pdml.net Sent: Sunday, January 16, 2005 10:17 AM Subject: RE: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments) I wouldn't be sure the D1 would focus/refocus at the same object every time!
Re: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments)
Hi, Herb Chong wrote: you're deliberately conflating two entirely different field's terminologies to make your point, just like JCO's pointless argument that no lens can possibly show anything 3D because the imaging surface is a flat plane. locking on in autofocus cameras means what i said. But _as Jens said_ it is not the same as locking on in weaponry, which is an active system compared to autofocus. Not the correct terminology, I know, but is the best descriptor I can use. IAC, I suspect we agree that a system where the photographer decides what is to be focused on is best. If we cannot have a system that will work to maintain focus (no matter where the focus point goes afterwards) once the lock is enabled, then present systems are the best we can hope for. Herb - Original Message - From: mike wilson [EMAIL PROTECTED] To: pentax-discuss@pdml.net Sent: Friday, January 14, 2005 3:49 PM Subject: Re: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments) Herb Chong wrote: you obviously haven't done any lately then. even the *istD locks onto flying birds. and it's one of the slowest out there nowadays at continuous AF. That's not the same as locking on.
Re: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments)
the Nikon and Canon cameras can track an object wandering across the FOV once it has acquired focus once, you don't even have to keep it on the same sensor. that's part of the reason the Canon 1Ds Mk2 has so many sensors. Herb... - Original Message - From: mike wilson [EMAIL PROTECTED] To: pentax-discuss@pdml.net Sent: Saturday, January 15, 2005 9:49 AM Subject: Re: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments) But _as Jens said_ it is not the same as locking on in weaponry, which is an active system compared to autofocus. Not the correct terminology, I know, but is the best descriptor I can use. IAC, I suspect we agree that a system where the photographer decides what is to be focused on is best. If we cannot have a system that will work to maintain focus (no matter where the focus point goes afterwards) once the lock is enabled, then present systems are the best we can hope for.
RE: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments)
I handled one of the very first five Canon D1's, when they first came to Europe (2001?) at a Canon presentation in Cork, Ireland. It had 45 focus points. The viewfinder was totally covered with focus points - they lit up like the neon lights of Las Vegas, when the camera was moved. The focus changed as fast as I could move the camera. And it took 4-8 frames every time I pressed the shutter (8 fps). It sounded like a freaking Uzi! Now, that's fast AF. Pentax never made anything close to that. Comparing this Canon to the *ist D is like comparing a Saab 9-3 to a Lamborghini Gallardo. Saab still make very nice cars, even though they are perhaps not the state of the art. The same goes for the Pentax *ist D, I suppose. About locking onto something: To me this means focusing on a subject, then stay focused at the same subject, even if it moves. No camera that I know of does this. Not even the Canon D1. Cameras loose focus when things move, but may refocus at the same subject after a while. Or it may focus on something else! That's not locking onto a subject, is it? Tracking perhaps, but certainly not locking. Jens Bladt mailto:[EMAIL PROTECTED] http://hjem.get2net.dk/bladt -Oprindelig meddelelse- Fra: Herb Chong [mailto:[EMAIL PROTECTED] Sendt: 16. januar 2005 00:04 Til: pentax-discuss@pdml.net Emne: Re: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments) the Nikon and Canon cameras can track an object wandering across the FOV once it has acquired focus once, you don't even have to keep it on the same sensor. that's part of the reason the Canon 1Ds Mk2 has so many sensors. Herb... - Original Message - From: mike wilson [EMAIL PROTECTED] To: pentax-discuss@pdml.net Sent: Saturday, January 15, 2005 9:49 AM Subject: Re: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments) But _as Jens said_ it is not the same as locking on in weaponry, which is an active system compared to autofocus. Not the correct terminology, I know, but is the best descriptor I can use. IAC, I suspect we agree that a system where the photographer decides what is to be focused on is best. If we cannot have a system that will work to maintain focus (no matter where the focus point goes afterwards) once the lock is enabled, then present systems are the best we can hope for.
Re: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments)
tracking and locking are the same thing in most manufacturer's literature. Herb - Original Message - From: Jens Bladt [EMAIL PROTECTED] To: pentax-discuss@pdml.net Sent: Saturday, January 15, 2005 6:43 PM Subject: RE: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments) About locking onto something: To me this means focusing on a subject, then stay focused at the same subject, even if it moves. No camera that I know of does this. Not even the Canon D1. Cameras loose focus when things move, but may refocus at the same subject after a while. Or it may focus on something else! That's not locking onto a subject, is it? Tracking perhaps, but certainly not locking.
Re: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments)
Herb Chong wrote: you obviously haven't done any lately then. even the *istD locks onto flying birds. and it's one of the slowest out there nowadays at continuous AF. That's not the same as locking on. Herb... - Original Message - From: mike wilson [EMAIL PROTECTED] To: pentax-discuss@pdml.net Sent: Thursday, January 13, 2005 5:50 PM Subject: Re: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments) In any case, I suspect Jens is saying that locking on in (autofocus) photography is not the same as locking on using guided weaponry. In other words, the weaponry will stay locked on to its target unless drastic countermeasures are undertaken. Cameras will change focus if the photographer breathes.
Re: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments)
you're deliberately conflating two entirely different field's terminologies to make your point, just like JCO's pointless argument that no lens can possibly show anything 3D because the imaging surface is a flat plane. locking on in autofocus cameras means what i said. Herb - Original Message - From: mike wilson [EMAIL PROTECTED] To: pentax-discuss@pdml.net Sent: Friday, January 14, 2005 3:49 PM Subject: Re: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments) Herb Chong wrote: you obviously haven't done any lately then. even the *istD locks onto flying birds. and it's one of the slowest out there nowadays at continuous AF. That's not the same as locking on.
Re: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments)
Hi, Herb Chong wrote: the February Popular Photography Your Best Shot column reproduces a USAF photo of a pilot ejecting from his F-16 as the plane was coming straight at the photographer. the camera locked onto the front of the airplane as it flew directly toward and then crashed to a stop about 100 feet from the photographer. it allowed him to take an in-focus image as it moved. the article captions says that the camera was a Nikon D1X, not noted for its AF speed, on a 300/2.8. figure the aircraft was travelling a couple of hundred miles an hour. http://www.rapp.org/archives/2004/01/thunderbird_crash/ Not a very good example at all. The photographer was almost certainly expecting the plane to be there (though maybe not doing _that_) and there is also a luck factor involved. There is also the good old English word bollocks to consider. In any case, I suspect Jens is saying that locking on in (autofocus) photography is not the same as locking on using guided weaponry. In other words, the weaponry will stay locked on to its target unless drastic countermeasures are undertaken. Cameras will change focus if the photographer breathes. mike Herb - Original Message - From: Jens Bladt [EMAIL PROTECTED] To: pentax-discuss@pdml.net Sent: Wednesday, January 12, 2005 2:19 AM Subject: RE: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments) Cameras cannot lock on to anything. Like an electronic weapon system in an F18-Hornet. I wish it could. It can only focus on a subject/distance. Then perhaps refocus on annother subject/distance.
Re: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments)
you obviously haven't done any lately then. even the *istD locks onto flying birds. and it's one of the slowest out there nowadays at continuous AF. Herb... - Original Message - From: mike wilson [EMAIL PROTECTED] To: pentax-discuss@pdml.net Sent: Thursday, January 13, 2005 5:50 PM Subject: Re: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments) In any case, I suspect Jens is saying that locking on in (autofocus) photography is not the same as locking on using guided weaponry. In other words, the weaponry will stay locked on to its target unless drastic countermeasures are undertaken. Cameras will change focus if the photographer breathes.
Re: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments)
why not? they are the same principle as optical target acquisition in a missile weapon system. not as smart, to be sure, but there is a human in back making sure that the camera is aimed at the target. Herb... - Original Message - From: Jens Bladt [EMAIL PROTECTED] To: pentax-discuss@pdml.net Sent: Wednesday, January 12, 2005 2:19 AM Subject: RE: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments) Cameras cannot lock on to anything. Like an electronic weapon system in an F18-Hornet. I wish it could. It can only focus on a subject/distance. Then perhaps refocus on annother subject/distance.
Re: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments)
the February Popular Photography Your Best Shot column reproduces a USAF photo of a pilot ejecting from his F-16 as the plane was coming straight at the photographer. the camera locked onto the front of the airplane as it flew directly toward and then crashed to a stop about 100 feet from the photographer. it allowed him to take an in-focus image as it moved. the article captions says that the camera was a Nikon D1X, not noted for its AF speed, on a 300/2.8. figure the aircraft was travelling a couple of hundred miles an hour. http://www.rapp.org/archives/2004/01/thunderbird_crash/ Herb - Original Message - From: Jens Bladt [EMAIL PROTECTED] To: pentax-discuss@pdml.net Sent: Wednesday, January 12, 2005 2:19 AM Subject: RE: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments) Cameras cannot lock on to anything. Like an electronic weapon system in an F18-Hornet. I wish it could. It can only focus on a subject/distance. Then perhaps refocus on annother subject/distance.
Re: Sigma 2.8 Zoom lens comments
On 2005-01-11, at 07:09, Alan Chan wrote: I am glad all the whining about the poor viewfinder years ago had finally paid off. Perhaps Pentax was listening afterall. vbg And thus they will probably finally improve AF in their future DSLRs many years from now ;-) -- Best regards Sylwek
Re: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments)
On 2005-01-11, at 00:47, John Coyle wrote: My experience with the AF of the MZ-S and the *istD tells me that the MZ-S is far better than the digital, with any of the lens I have used on both cameras. I find the MZ-S very quick and accurate, and able to AF in very dim conditions and low contrast. On the other hand, using the *istD at a wedding on Saturday, I got only two focussed shots in a 6-7 second opportunity (when the couple were walking back down the aisle after the ceremony) using AF-C and the SMC-Takumar 28-105 4-5.6: sensitivity 400ASA and exposures were in the 1/60 @ 4.5 to1/90 @ 5.6 region. I have to confess that this is my first real disappointment with the *istD: perhaps, however, it was due to battery state, as I did get the half-full to empty warning several times during about an hour's use - turning it off and back on again gave me a full indicator every time though! Alternatively, the state of the batteries together with the fact that this is a solid and heavy lens may have contributed. This is exactly the same experience as mine. And that was a reason why I had to sell *istD - disappointment during weddings at low light. For film use I still have MZ-S, which has very good (enough for action shots during wedding) low-light AF. -- Best regards Sylwek
Re: Sigma 2.8 Zoom lens comments
that's only showing your ignrance of how AF works. Herb - Original Message - From: Shel Belinkoff [EMAIL PROTECTED] To: pentax-discuss@pdml.net Sent: Monday, January 10, 2005 11:27 PM Subject: Re: Sigma 2.8 Zoom lens comments That's a red herring, Herb. We're talking about auto focus and how YOU choose to use it in a certain situation. Something is either in focus or it's not, and whether your pics are in focus because you rely of DOF rather than the focusing accuracy of the camera.
Re: Sigma 2.8 Zoom lens comments
you didn't even understand the issue. i can achieve focus lock under entirely dark conditions while Bill wasn't able to. that was the point. Herb - Original Message - From: Shel Belinkoff [EMAIL PROTECTED] To: pentax-discuss@pdml.net Sent: Monday, January 10, 2005 11:27 PM Subject: Re: Sigma 2.8 Zoom lens comments That's a red herring, Herb. We're talking about auto focus and how YOU choose to use it in a certain situation. Something is either in focus or it's not, and whether your pics are in focus because you rely of DOF rather than the focusing accuracy of the camera.
Re: Sigma 2.8 Zoom lens comments
- Original Message - From: Herb Chong Subject: Re: Sigma 2.8 Zoom lens comments you didn't even understand the issue. i can achieve focus lock under entirely dark conditions while Bill wasn't able to. that was the point. I think our entirely dark conditions must differ enough that what I am shooting is much harder on the camera. William Robb
Re: Sigma 2.8 Zoom lens comments
Perhaps Pentax was listening afterall. vbg Based on my years with this list, I'd say their hearing is very selective. Kenneth Waller -Original Message- From: Sylwester Pietrzyk [EMAIL PROTECTED] Subject: Re: Sigma 2.8 Zoom lens comments On 2005-01-11, at 07:09, Alan Chan wrote: I am glad all the whining about the poor viewfinder years ago had finally paid off. Perhaps Pentax was listening afterall. vbg And thus they will probably finally improve AF in their future DSLRs many years from now ;-) PeoplePC Online A better way to Internet http://www.peoplepc.com
Re: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments)
Boy, you have me confused. I have shot a lot of weddings, and I don't recall action shots being a part of it. If you can't focus follow someone walking down the aisle, then perhaps you might consider that action. I never use AF for weddings. -- Best regards, Bruce Tuesday, January 11, 2005, 2:26:19 AM, you wrote: SP On 2005-01-11, at 00:47, John Coyle wrote: My experience with the AF of the MZ-S and the *istD tells me that the MZ-S is far better than the digital, with any of the lens I have used on both cameras. I find the MZ-S very quick and accurate, and able to AF in very dim conditions and low contrast. On the other hand, using the *istD at a wedding on Saturday, I got only two focussed shots in a 6-7 second opportunity (when the couple were walking back down the aisle after the ceremony) using AF-C and the SMC-Takumar 28-105 4-5.6: sensitivity 400ASA and exposures were in the 1/60 @ 4.5 to1/90 @ 5.6 region. I have to confess that this is my first real disappointment with the *istD: perhaps, however, it was due to battery state, as I did get the half-full to empty warning several times during about an hour's use - turning it off and back on again gave me a full indicator every time though! Alternatively, the state of the batteries together with the fact that this is a solid and heavy lens may have contributed. SP This is exactly the same experience as mine. And that was a reason why SP I had to sell *istD - disappointment during weddings at low light. For SP film use I still have MZ-S, which has very good (enough for action SP shots during wedding) low-light AF. SP -- SP Best regards SP Sylwek
RE: Sigma 2.8 Zoom lens comments
They still don't - and never will (if it's reflected metering/a built-in one), until you find a way to tell it, whether you are photographing a white horse or a black cow. You have to know, the camera/meter doesn't. Both should be exposed exactly the same. No meter will suggest that (incident metering exempted). Jens Bladt mailto:[EMAIL PROTECTED] http://hjem.get2net.dk/bladt -Oprindelig meddelelse- Fra: Herb Chong [mailto:[EMAIL PROTECTED] Sendt: 11. januar 2005 02:55 Til: pentax-discuss@pdml.net Emne: Re: Sigma 2.8 Zoom lens comments how long has it been since light meters gave perfect exposure every time? Herb - Original Message - From: Shel Belinkoff [EMAIL PROTECTED] To: pentax-discuss@pdml.net Sent: Monday, January 10, 2005 11:48 AM Subject: RE: Sigma 2.8 Zoom lens comments If you're paying for AF the feature should work properly, every time. It's been about twenty years since the inception of AF cameras and you'd think that by now the technology would be refined enough so that complaints and concerns would be nonexistent. It seems to me that fast focusing in low light would be the raison d'etre for AF.
Re: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments)
Bruce Dayton wrote on 11.01.05 16:29: Boy, you have me confused. I have shot a lot of weddings, and I don't recall action shots being a part of it. If you can't focus follow someone walking down the aisle, then perhaps you might consider that action. I never use AF for weddings. Bruce, it's all a matter of habbits. If I'm used to using AF in these situations, than I shouldn't change my habbits should I? ;-) -- Balance is the ultimate good... Best Regards Sylwek
Re: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments)
- Original Message - From: Bruce Dayton Subject: Re: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments) Boy, you have me confused. I have shot a lot of weddings, and I don't recall action shots being a part of it. If you can't focus follow someone walking down the aisle, then perhaps you might consider that action. I never use AF for weddings. The istD seems to have a very steep AF falloff, it goes from quite good (my experience is limited, I admit) to totally useless within about 1EV of light. He was using AF-C, which is a great way to get out of focus images. William Robb
(Now OT): Re: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments)
Sylwek wrote: And that was a reason why I had to sell *istD - disappointment during weddings at low light. Then Bruce wrote: Boy, you have me confused. I have shot a lot of weddings, and I don't recall action shots being a part of it. I believe he was referring to the ancient custom, still practiced in some remote villages, wherein the bridesmaids perform a whirling sword dance while tossing babies in the air, while the groom's friends ride a circle around them on half-wild horses batting a severed sheep's head with long poles. The *ist D's autofocus performance won't handle a situation like that. Joe
RE: (Now OT): Re: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments)
I believe he was referring to the ancient custom, still practiced in some remote villages, wherein the bridesmaids perform a whirling sword dance while tossing babies in the air, while the groom's friends ride a circle around them on half-wild horses batting a severed sheep's head with long poles. The *ist D's autofocus performance won't handle a situation like that. Joe Those you call the deliberate soft focus shots.
Re: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments)
Hello Sylwester, Guess I'm with Shel on this one. My experience with AF is that it is either inprecise or that it tends to cause you to compose poorer than you would have using manual focus. Here is my reasoning. The AF sensor (doesn't matter camera brand) is of a certain size. When the focal length changes, the area covered by the sensor changes. It is entirely possible and quite probable that many times, the sensor covers an area that has depth to it. Now in that situation, the exact focus point can be arbitrarily somewhere in the sensor area and on top of that, somewhere in the area marked in the viewfinder. So what you get is a picture that isn't focused exactly where you want it. For many people that is good enough - they don't care beyond that. For me, it is bothersome. My niece is a full-time working pro shooting multiple weddings weekly. Very large volume and has mostly been shooting a Nikon D1X. I have sat down and gone through quite a large number of her pictures and found that many times, the AF put the focus on part of the nose instead of the eyes, etc. In other words, the AF missed the precise spot. Something was focused, just not the desired location. When viewed small, the miss was not noticeable, but if the client asked for an 8X10, they would see it. If you subscribe to the focus lock on subject, then recompose style of AF (I do), then I find that I get lazy, especially in a quicker moving situation and end up having the subject more centered than I really want. I grew up on manual cameras like the OM-1 and MX. The style I shoot is meter, compose, focus, shoot. My images are much better when I do it that way. When shooting AF, it is more like set camera to program or AV, focus, compose, shoot - usually the metering is quite as good and the composition suffers because the AF point becomes more important than the composition. I guess I am saying that I consider AF to be a bad habit. I agree there are situations that should use AF, but weddings is not one of them. I guess we will have to disagree on this one. -- Best regards, Bruce Tuesday, January 11, 2005, 8:03:10 AM, you wrote: SP Bruce Dayton wrote on 11.01.05 16:29: Boy, you have me confused. I have shot a lot of weddings, and I don't recall action shots being a part of it. If you can't focus follow someone walking down the aisle, then perhaps you might consider that action. I never use AF for weddings. SP Bruce, it's all a matter of habbits. If I'm used to using AF in these SP situations, than I shouldn't change my habbits should I? ;-)
Re: Sigma 2.8 Zoom lens comments
Just an OT kinda question... did anyone actually have any comments about the Sigma 2.8 24-70 DG DF zoom lens? thanx dk
Re: Sigma 2.8 Zoom lens comments
i understand that your typical usage conditions are harder. parameterize harder though. it's not just low light, as i can easily show. i'm not even sure that it is a low contrast subject, at least of the ones you photograph. i think that it's moving subjects. Herb... - Original Message - From: William Robb [EMAIL PROTECTED] To: pentax-discuss@pdml.net Sent: Tuesday, January 11, 2005 7:31 AM Subject: Re: Sigma 2.8 Zoom lens comments I think our entirely dark conditions must differ enough that what I am shooting is much harder on the camera.
Re: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments)
as far as i am concerned, a camera with good AF should lock on the person as they are at the end of the aisle and easily track as they approach, if they are the only person advancing. they are not moving that fast and the lighting isn't that bad either. i also understand how the AF system can be fooled into locking on the wrong thing first and after that, all bets are off. Herb - Original Message - From: Bruce Dayton [EMAIL PROTECTED] To: Sylwester Pietrzyk pentax-discuss@pdml.net Sent: Tuesday, January 11, 2005 10:29 AM Subject: Re: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments) Boy, you have me confused. I have shot a lot of weddings, and I don't recall action shots being a part of it. If you can't focus follow someone walking down the aisle, then perhaps you might consider that action. I never use AF for weddings.
Re: Sigma 2.8 Zoom lens comments
so why expect AF systems to be perfect? Shel said why pay for something that doesn't work perfectly. Herb - Original Message - From: Jens Bladt [EMAIL PROTECTED] To: pentax-discuss@pdml.net Sent: Tuesday, January 11, 2005 10:40 AM Subject: RE: Sigma 2.8 Zoom lens comments They still don't - and never will (if it's reflected metering/a built-in one), until you find a way to tell it, whether you are photographing a white horse or a black cow. You have to know, the camera/meter doesn't. Both should be exposed exactly the same. No meter will suggest that (incident metering exempted).
Re: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments)
There are an awful lot of possible points of focus on a person - ear, eye, nose, mouth, chin, forehead, etc. Locking on to what is exactly the problem. On top of that, they are usually not the only person advancing and arms and heads of people in the aisle can suddenly swing out in between the camera and the subject. And you may have to change focus points rapidly if the subject is tall or short or left side or right side. I don't think it is a question of just good AF. -- Best regards, Bruce Tuesday, January 11, 2005, 4:05:26 PM, you wrote: HC as far as i am concerned, a camera with good AF should lock on the person as HC they are at the end of the aisle and easily track as they approach, if they HC are the only person advancing. they are not moving that fast and the HC lighting isn't that bad either. i also understand how the AF system can be HC fooled into locking on the wrong thing first and after that, all bets are HC off. HC Herb HC - Original Message - HC From: Bruce Dayton [EMAIL PROTECTED] HC To: Sylwester Pietrzyk pentax-discuss@pdml.net HC Sent: Tuesday, January 11, 2005 10:29 AM HC Subject: Re: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments) Boy, you have me confused. I have shot a lot of weddings, and I don't recall action shots being a part of it. If you can't focus follow someone walking down the aisle, then perhaps you might consider that action. I never use AF for weddings.
Re: Sigma 2.8 Zoom lens comments
Herb, I'm with you on this. I don't expect the AF to be perfect. It is a tool just like the light meter. Used in a smart fashion, it can be very helpful. Heavily relying on it instead of your photographic skills can cause you to end up with an image you didn't intend. -- Best regards, Bruce Tuesday, January 11, 2005, 4:06:33 PM, you wrote: HC so why expect AF systems to be perfect? Shel said why pay for something that HC doesn't work perfectly. HC Herb HC - Original Message - HC From: Jens Bladt [EMAIL PROTECTED] HC To: pentax-discuss@pdml.net HC Sent: Tuesday, January 11, 2005 10:40 AM HC Subject: RE: Sigma 2.8 Zoom lens comments They still don't - and never will (if it's reflected metering/a built-in one), until you find a way to tell it, whether you are photographing a HC white horse or a black cow. You have to know, the camera/meter doesn't. Both should be exposed exactly the same. No meter will suggest that (incident metering exempted).
Re: Sigma 2.8 Zoom lens comments
i use AF about 80% of the time because it works perfectly about that often. i know when it doesn't work by looking through the viewfinder and also by the AF lock light. i know enough about the DOF i get with most of the lenses i use that i don't need DOF preview to know what's going to be in acceptable focus and what isn't. although most of my landscapes are shot at smaller apertures to get the best combination of DOF and sharpness, whenever, i shoot wildlife, it's essentuially always wide open to get high shutter speeds. knowing the conditions under which my AF works reliably means that i can ignore the step of manually focusing and concentrate on composition under those conditions. since i also know when the metering system works reliably, i know that most of the time, i can ignore the meter except for confirming that i am getting the right shutter speeds for the effects i am after if i am shooting flowing water or similar subjects where i want intentional blurring. by knowing that i can trust my AF and metering to work correctly under most circumstances i shoot under and when they fail to work, i don't have to think about anything except composition most of the time. i let the camera do what it is good at and know when to override. it's my compositions and sense of timing that distinguishes my images from others and enables me to sell them, not my ability to expose and focus correctly. that's assumed and a commodity in my specialty. Herb - Original Message - From: Bruce Dayton [EMAIL PROTECTED] To: Herb Chong pentax-discuss@pdml.net Sent: Tuesday, January 11, 2005 7:22 PM Subject: Re: Sigma 2.8 Zoom lens comments Herb, I'm with you on this. I don't expect the AF to be perfect. It is a tool just like the light meter. Used in a smart fashion, it can be very helpful. Heavily relying on it instead of your photographic skills can cause you to end up with an image you didn't intend.
RE: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments)
Cameras cannot lock on to anything. Like an electronic weapon system in an F18-Hornet. I wish it could. It can only focus on a subject/distance. Then perhaps refocus on annother subject/distance. Jens Bladt mailto:[EMAIL PROTECTED] http://hjem.get2net.dk/bladt -Oprindelig meddelelse- Fra: Bruce Dayton [mailto:[EMAIL PROTECTED] Sendt: 12. januar 2005 01:20 Til: Herb Chong Emne: Re: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments) There are an awful lot of possible points of focus on a person - ear, eye, nose, mouth, chin, forehead, etc. Locking on to what is exactly the problem. On top of that, they are usually not the only person advancing and arms and heads of people in the aisle can suddenly swing out in between the camera and the subject. And you may have to change focus points rapidly if the subject is tall or short or left side or right side. I don't think it is a question of just good AF. -- Best regards, Bruce Tuesday, January 11, 2005, 4:05:26 PM, you wrote: HC as far as i am concerned, a camera with good AF should lock on the person as HC they are at the end of the aisle and easily track as they approach, if they HC are the only person advancing. they are not moving that fast and the HC lighting isn't that bad either. i also understand how the AF system can be HC fooled into locking on the wrong thing first and after that, all bets are HC off. HC Herb HC - Original Message - HC From: Bruce Dayton [EMAIL PROTECTED] HC To: Sylwester Pietrzyk pentax-discuss@pdml.net HC Sent: Tuesday, January 11, 2005 10:29 AM HC Subject: Re: *istD AF performance (was Re: Sigma 2.8 Zoom lens comments) Boy, you have me confused. I have shot a lot of weddings, and I don't recall action shots being a part of it. If you can't focus follow someone walking down the aisle, then perhaps you might consider that action. I never use AF for weddings.
Re: Sigma 2.8 Zoom lens comments
have you tried any other camera using AF under similar conditions? Herb - Original Message - From: William Robb [EMAIL PROTECTED] To: Pentax Discuss pentax-discuss@pdml.net Sent: Sunday, January 09, 2005 10:20 PM Subject: Re: Sigma 2.8 Zoom lens comments I tend to shoot moving subjects with the istD. In low light I can do the focus better myself. I still do my landscapes on a 4x5. Every one is correctly focussed G.
Re: Sigma 2.8 Zoom lens comments
My only expereince in lowish light with the istD is with my 28-105 f 4-5.6. It seems to be fine,for what i have tested on sofar.Even the Sigma 100-300 DL f5.6-6.3 focused well Sunday in extremly dull and flat contrast conditions.The print showed that,however snow lacked all detail in the print,the subjects were fine. However dont forget AF does not like certain items to try and focus on(Geeez, look what group i'm saying this to.LOL). Go ahead and laugh,cause i know you will,but my PZ-1 and my istD lock on quicker then my D1 and sometimes my D2H. With the Nikons it tends to back focus first then lock on.(the D1 more than the other)Not all the time but often enough to be a real pain. I often find my self having to focus,lower the unit, focus, then raise it back up to the subject then focus again then it looks good.Althewill getting the green infocus light in the finder. 1D-MkII users start you laughing now.:-) Dave Brooks I'd be surprised if a faster lens doesn't help low light autofocus performance. However, I have no data to back that up. Although I rarely use autofocus lenses, I'd be interested in any real test results. I was afraid of that. Thanks for the info. Chad On Sun, 09 Jan 2005 16:34:49 -0700, Joseph Tainter [EMAIL PROTECTED] wrote: Poor autofocus performance in low light is a characteristic of the *ist D. A faster lens will not help. In low light with my FA 50 f1.7 on the D, autofocus is slow to impossible. Joe
Re: Sigma 2.8 Zoom lens comments
No, the istD is the only AF cameras I have used for any significant number of pictures. William Robb - Original Message - From: Herb Chong Subject: Re: Sigma 2.8 Zoom lens comments have you tried any other camera using AF under similar conditions? I tend to shoot moving subjects with the istD. In low light I can do the focus better myself. I still do my landscapes on a 4x5. Every one is correctly focussed G.
RE: Sigma 2.8 Zoom lens comments
I think the slow AF of the *ist D is related to a rather weak focus motor, not the optics. It seems to be equally slow no matter what lens is used. The AF of the MZ-S is much better - it works so fast, that the camera actually moves in my hand when I press the shutter release half way down. The focus motor is better/faster/stronger. I wish the *ist D worked this well. I think this is a stupid place for Petnax to save money, because of the marketing issue. FWIW I think the AF works quitewell, though. I takes a second or so to focus, which is not very fast, but most of the time it's good enough, but certainly not impressing. For very fast foucsing in low light I tend to sweitch off the AF. But this takes time as well. Jens Bladt mailto:[EMAIL PROTECTED] http://hjem.get2net.dk/bladt -Oprindelig meddelelse- Fra: Herb Chong [mailto:[EMAIL PROTECTED] Sendt: 10. januar 2005 02:05 Til: pentax-discuss@pdml.net Emne: Re: Sigma 2.8 Zoom lens comments i read about this slow or useless AF performance in low light on the *istD comment and i wonder every time what is really going on. i shoot a lot of waterfall shots with a 10 stop ND filter mounted. that gives me typically 8 second exposures at f11 or f13 at ISO 200. i set the camera to point select AF mode, choose a focus point, press the shutter release half way, it focuses and lock correctly (usually on the first try), and i take my picture. the 10 stop filter is mounted while i am doing this. it's almost impossible to see *anything* in the viewfinder except the readouts, yet the AF works and i get correctly focused images pretty much all the time. Herb... - Original Message - From: Geheim [EMAIL PROTECTED] To: pentax-discuss@pdml.net Sent: Sunday, January 09, 2005 7:40 PM Subject: Re: Sigma 2.8 Zoom lens comments The comments so far do not surprise me much. It was just an idea I had :) I'm hoping someone that has used one of these zooms will chime in in the next few days. My money might be better spent picking up some fast primes, AF or M.
RE: Sigma 2.8 Zoom lens comments
If you're paying for AF the feature should work properly, every time. It's been about twenty years since the inception of AF cameras and you'd think that by now the technology would be refined enough so that complaints and concerns would be nonexistent. It seems to me that fast focusing in low light would be the raison d'etre for AF. Similarly, perhaps too many people have come to rely on AF in too many situations like the one Herb described. What need is there for AF when the camera's tripod mounted and the subject is stationary, like rocks and trees and waterfalls? Instead of getting all shots well focused Herb gets correctly focused images pretty much all the time, and seems to be relying on DOF to get sharply focused pics. While that may be OK in some situations it's easy to imagine situations where minimal DOF would be appropriate for certain photographs, or where shorter shutter speeds would be a better choice. Shel From: Jens Bladt [EMAIL PROTECTED] I think the slow AF of the *ist D is related to a rather weak focus motor, not the optics. It seems to be equally slow no matter what lens is used. The AF of the MZ-S is much better - it works so fast, that the camera actually moves in my hand when I press the shutter release half way down. The focus motor is better/faster/stronger. I wish the *ist D worked this well. I think this is a stupid place for Petnax to save money, because of the marketing issue. FWIW I think the AF works quitewell, though. I takes a second or so to focus, which is not very fast, but most of the time it's good enough, but certainly not impressing. For very fast foucsing in low light I tend to sweitch off the AF. But this takes time as well.
RE: Sigma 2.8 Zoom lens comments
I can't say that I disagree there, Shel. However, in my experience long distance focusing is better with AF. For shots like this, AF is better, especially with the *ist D, with no great focusing help (split field or similar) in the viewfinder: http://images1.fotopic.net/?iid=y5kj3uoutx=600noresize=1nostamp=1 For shots like this, AF speed is not a big issue, though. Jens Bladt mailto:[EMAIL PROTECTED] http://hjem.get2net.dk/bladt -Oprindelig meddelelse- Fra: Shel Belinkoff [mailto:[EMAIL PROTECTED] Sendt: 10. januar 2005 17:48 Til: pentax-discuss@pdml.net Emne: RE: Sigma 2.8 Zoom lens comments If you're paying for AF the feature should work properly, every time. It's been about twenty years since the inception of AF cameras and you'd think that by now the technology would be refined enough so that complaints and concerns would be nonexistent. It seems to me that fast focusing in low light would be the raison d'etre for AF. Similarly, perhaps too many people have come to rely on AF in too many situations like the one Herb described. What need is there for AF when the camera's tripod mounted and the subject is stationary, like rocks and trees and waterfalls? Instead of getting all shots well focused Herb gets correctly focused images pretty much all the time, and seems to be relying on DOF to get sharply focused pics. While that may be OK in some situations it's easy to imagine situations where minimal DOF would be appropriate for certain photographs, or where shorter shutter speeds would be a better choice. Shel From: Jens Bladt [EMAIL PROTECTED] I think the slow AF of the *ist D is related to a rather weak focus motor, not the optics. It seems to be equally slow no matter what lens is used. The AF of the MZ-S is much better - it works so fast, that the camera actually moves in my hand when I press the shutter release half way down. The focus motor is better/faster/stronger. I wish the *ist D worked this well. I think this is a stupid place for Petnax to save money, because of the marketing issue. FWIW I think the AF works quitewell, though. I takes a second or so to focus, which is not very fast, but most of the time it's good enough, but certainly not impressing. For very fast foucsing in low light I tend to sweitch off the AF. But this takes time as well.
Re: Sigma 2.8 Zoom lens comments
In the past, my other AF Pentax bodies have focused fine in situations where the *istD does not. I was throw off by this. It seems the *istD has issues with AF in certain situations. That is when I had the idea of getting a faster zoom in place of the 16-45 4.0 I have now for the *istD. It was just an idea. :) After reading the comments here, I'm going to pickup a few more primes and keep the Pentax digital zoom. That zoom comes in handy sometimes. Thanks, Chad
RE: Sigma 2.8 Zoom lens comments
From: Jens Bladt [EMAIL PROTECTED] I think the slow AF of the *ist D is related to a rather weak focus motor, not the optics. It seems to be equally slow no matter what lens is used. The AF of the MZ-S is much better - it works so fast, that the camera actually moves in my hand when I press the shutter release half way down. The focus motor is better/faster/stronger. I wish the *ist D worked this well. I think this is a stupid place for Petnax to save money, because of the marketing issue. Quite possible weaker AF motor was used for 2 reasons - keep the cost and the power consumption of the D/DS down. MZ/ZX bodies have weaker AF motor than the Z-1/Z-1p for the same reason. = Alan Chan http://www.pbase.com/wlachan __ Do you Yahoo!? Yahoo! Mail - Easier than ever with enhanced search. Learn more. http://info.mail.yahoo.com/mail_250
RE: Sigma 2.8 Zoom lens comments
MZ/ZX bodies have weaker AF motor than the Z-1/Z-1p for the same reason. Does this go for the MZ-S as well Anyway, the PZ-1p has nice and quite fast AF. Jens Bladt mailto:[EMAIL PROTECTED] http://hjem.get2net.dk/bladt -Oprindelig meddelelse- Fra: Alan Chan [mailto:[EMAIL PROTECTED] Sendt: 10. januar 2005 20:15 Til: pentax-discuss@pdml.net Emne: RE: Sigma 2.8 Zoom lens comments From: Jens Bladt [EMAIL PROTECTED] I think the slow AF of the *ist D is related to a rather weak focus motor, not the optics. It seems to be equally slow no matter what lens is used. The AF of the MZ-S is much better - it works so fast, that the camera actually moves in my hand when I press the shutter release half way down. The focus motor is better/faster/stronger. I wish the *ist D worked this well. I think this is a stupid place for Petnax to save money, because of the marketing issue. Quite possible weaker AF motor was used for 2 reasons - keep the cost and the power consumption of the D/DS down. MZ/ZX bodies have weaker AF motor than the Z-1/Z-1p for the same reason. = Alan Chan http://www.pbase.com/wlachan __ Do you Yahoo!? Yahoo! Mail - Easier than ever with enhanced search. Learn more. http://info.mail.yahoo.com/mail_250
RE: Sigma 2.8 Zoom lens comments
--- Jens Bladt [EMAIL PROTECTED] wrote: Does this go for the MZ-S as well Anyway, the PZ-1p has nice and quite fast AF. I believe so because the MZ-S doesn't have the space to fit a bigger and more powerful motor. = Alan Chan http://www.pbase.com/wlachan __ Do you Yahoo!? Yahoo! Mail - now with 250MB free storage. Learn more. http://info.mail.yahoo.com/mail_250
Re: Sigma 2.8 Zoom lens comments
On Sun, 9 Jan 2005 20:05:11 -0500, Herb Chong wrote: i read about this slow or useless AF performance in low light on the *istD comment and i wonder every time what is really going on. i shoot a lot of waterfall shots with a 10 stop ND filter mounted. that gives me typically 8 second exposures at f11 or f13 at ISO 200. i set the camera to point select AF mode, choose a focus point, press the shutter release half way, it focuses and lock correctly (usually on the first try), and i take my picture. the 10 stop filter is mounted while i am doing this. it's almost impossible to see *anything* in the viewfinder except the readouts, yet the AF works and i get correctly focused images pretty much all the time. There are 2 problems with all this discussion. One is that there is no definition of low light, the other is that in truth the problem with the autofocus is with low contrast rather than low light. In day light even with a 10 stop ND filter there is still the inherent contrast in the image to capture focus. In near dark situations the light is generally very diffused which cuts down on contrast and makes it harder for the AF to find something to lock on to. Leon http://www.bluering.org.au http://www.bluering.org.au/leon
Re: Sigma 2.8 Zoom lens comments
Monday, January 10, 2005, 1:40:41 AM, Geheim wrote: G The comments so far do not surprise me much. It was just an idea I had G :) I'm hoping someone that has used one of these zooms will chime in G in the next few days. Hi Chad, you can search the archives of the list (www.pdml.net) and find there my post about the Sigma 2.8 18-50 DC. it's a rather long, several pages long result of some testing and observations, so I won't clutter the list with it again. Or I can send it to you directly, if I can find it in my computer. When time permits, I can post some images from my tryout of the lens. But images aren't worth a thousand words, unfortunately, and are uncomparable to other images as there are too many variables (my camera is wholy different brand, I use different raw converter, which does some adaptive sharpening or something similar, et cetera...) Of the other lens, the 17-35 2.8-4 EX DG. I have asked about this lens a lot as it is very cheap to come by used. There are now two versions, but for Pentax probably only the first version is made (the second, had HSM added in Nikon mount, and changed cosmetics). I don't know if they differ optically. But several pros here used it, for news work, before their employers gave them something better, and I have asked few times about it. Based on what I heard from people who know what a good lens is, I would advise against this lens. According to all I asked, it exhibits many optical aberations, making it a bow-wow lens, in other words a dog (or a cat, depending on your point of view g). It was also a bit flimsey construction. Again, it might have been sample variation or their hyperbole, Good light! fra
*istD AF performance (was Re: Sigma 2.8 Zoom lens comments)
My experience with the AF of the MZ-S and the *istD tells me that the MZ-S is far better than the digital, with any of the lens I have used on both cameras. I find the MZ-S very quick and accurate, and able to AF in very dim conditions and low contrast. On the other hand, using the *istD at a wedding on Saturday, I got only two focussed shots in a 6-7 second opportunity (when the couple were walking back down the aisle after the ceremony) using AF-C and the SMC-Takumar 28-105 4-5.6: sensitivity 400ASA and exposures were in the 1/60 @ 4.5 to1/90 @ 5.6 region. I have to confess that this is my first real disappointment with the *istD: perhaps, however, it was due to battery state, as I did get the half-full to empty warning several times during about an hour's use - turning it off and back on again gave me a full indicator every time though! Alternatively, the state of the batteries together with the fact that this is a solid and heavy lens may have contributed. John Coyle Brisbane, Australia
Re: Sigma 2.8 Zoom lens comments
my point was that virtually any camera would not have autofocused either under the conditions Bill was thinking of. Herb - Original Message - From: Jens Bladt [EMAIL PROTECTED] To: pentax-discuss@pdml.net Sent: Monday, January 10, 2005 11:29 AM Subject: RE: Sigma 2.8 Zoom lens comments FWIW I think the AF works quitewell, though. I takes a second or so to focus, which is not very fast, but most of the time it's good enough, but certainly not impressing. For very fast foucsing in low light I tend to sweitch off the AF. But this takes time as well.
Re: Sigma 2.8 Zoom lens comments
how long has it been since light meters gave perfect exposure every time? Herb - Original Message - From: Shel Belinkoff [EMAIL PROTECTED] To: pentax-discuss@pdml.net Sent: Monday, January 10, 2005 11:48 AM Subject: RE: Sigma 2.8 Zoom lens comments If you're paying for AF the feature should work properly, every time. It's been about twenty years since the inception of AF cameras and you'd think that by now the technology would be refined enough so that complaints and concerns would be nonexistent. It seems to me that fast focusing in low light would be the raison d'etre for AF.
Re: Sigma 2.8 Zoom lens comments
Thanks for info. I'll look up the lens in the archive. Chad On Mon, 10 Jan 2005 11:56:03 +0100, Frantisek [EMAIL PROTECTED] wrote: Monday, January 10, 2005, 1:40:41 AM, Geheim wrote: G The comments so far do not surprise me much. It was just an idea I had G :) I'm hoping someone that has used one of these zooms will chime in G in the next few days. Hi Chad, you can search the archives of the list (www.pdml.net) and find there my post about the Sigma 2.8 18-50 DC. it's a rather long, several pages long result of some testing and observations, so I won't clutter the list with it again. Or I can send it to you directly, if I can find it in my computer. When time permits, I can post some images from my tryout of the lens. But images aren't worth a thousand words, STUFF DELETED
Re: Sigma 2.8 Zoom lens comments
That's a red herring, Herb. We're talking about auto focus and how YOU choose to use it in a certain situation. Something is either in focus or it's not, and whether your pics are in focus because you rely of DOF rather than the focusing accuracy of the camera. Shel [Original Message] From: Herb Chong [EMAIL PROTECTED] To: pentax-discuss@pdml.net Date: 1/10/2005 5:57:23 PM Subject: Re: Sigma 2.8 Zoom lens comments how long has it been since light meters gave perfect exposure every time? Herb - Original Message - From: Shel Belinkoff [EMAIL PROTECTED] To: pentax-discuss@pdml.net Sent: Monday, January 10, 2005 11:48 AM Subject: RE: Sigma 2.8 Zoom lens comments If you're paying for AF the feature should work properly, every time. It's been about twenty years since the inception of AF cameras and you'd think that by now the technology would be refined enough so that complaints and concerns would be nonexistent. It seems to me that fast focusing in low light would be the raison d'etre for AF.
Re: Sigma 2.8 Zoom lens comments
- Original Message - From: Herb Chong Subject: Re: Sigma 2.8 Zoom lens comments my point was that virtually any camera would not have autofocused either under the conditions Bill was thinking of. I pretty much knew that already. The Canon and Nikon boys have had trouble at the events I have seen them at. I point of fact, because AF doesn't work well in the stuff I seem to find myself doing, the better viewfinder on the Pentax is a major advantage. I do like the multi point AF in the studio, although I find that often I can't get a focus point right where I want it. With static subjects, I find it easier to manually focus than to utilize AF. YMMV. William Robb
Re: Sigma 2.8 Zoom lens comments
--- William Robb [EMAIL PROTECTED] wrote: I point of fact, because AF doesn't work well in the stuff I seem to find myself doing, the better viewfinder on the Pentax is a major advantage. I am glad all the whining about the poor viewfinder years ago had finally paid off. Perhaps Pentax was listening afterall. vbg = Alan Chan http://www.pbase.com/wlachan __ Do you Yahoo!? Take Yahoo! Mail with you! Get it on your mobile phone. http://mobile.yahoo.com/maildemo
Re: Sigma 2.8 Zoom lens comments
Poor autofocus performance in low light is a characteristic of the *ist D. A faster lens will not help. In low light with my FA 50 f1.7 on the D, autofocus is slow to impossible. Joe
Re: Sigma 2.8 Zoom lens comments
I was afraid of that. Thanks for the info. Chad On Sun, 09 Jan 2005 16:34:49 -0700, Joseph Tainter [EMAIL PROTECTED] wrote: Poor autofocus performance in low light is a characteristic of the *ist D. A faster lens will not help. In low light with my FA 50 f1.7 on the D, autofocus is slow to impossible. Joe
Re: Sigma 2.8 Zoom lens comments
I'd be surprised if a faster lens doesn't help low light autofocus performance. However, I have no data to back that up. Although I rarely use autofocus lenses, I'd be interested in any real test results. I was afraid of that. Thanks for the info. Chad On Sun, 09 Jan 2005 16:34:49 -0700, Joseph Tainter [EMAIL PROTECTED] wrote: Poor autofocus performance in low light is a characteristic of the *ist D. A faster lens will not help. In low light with my FA 50 f1.7 on the D, autofocus is slow to impossible. Joe
Re: Sigma 2.8 Zoom lens comments
- Original Message - From: [EMAIL PROTECTED] Subject: Re: Sigma 2.8 Zoom lens comments I'd be surprised if a faster lens doesn't help low light autofocus performance. However, I have no data to back that up. Although I rarely use autofocus lenses, I'd be interested in any real test results. No real test results, but I have to agree with Joe on this one. I don't use zooms much, and never in low light, most of the time the lenses I have on my istD are f/2 and faster. My experience with the AF in low light is pretty dismal. In my case, I think a slower lens would only make the AF performance worse than the useless that it already is. William Robb
Re: Sigma 2.8 Zoom lens comments
The comments so far do not surprise me much. It was just an idea I had :) I'm hoping someone that has used one of these zooms will chime in in the next few days. My money might be better spent picking up some fast primes, AF or M. Chad
Re: Sigma 2.8 Zoom lens comments
i read about this slow or useless AF performance in low light on the *istD comment and i wonder every time what is really going on. i shoot a lot of waterfall shots with a 10 stop ND filter mounted. that gives me typically 8 second exposures at f11 or f13 at ISO 200. i set the camera to point select AF mode, choose a focus point, press the shutter release half way, it focuses and lock correctly (usually on the first try), and i take my picture. the 10 stop filter is mounted while i am doing this. it's almost impossible to see *anything* in the viewfinder except the readouts, yet the AF works and i get correctly focused images pretty much all the time. Herb... - Original Message - From: Geheim [EMAIL PROTECTED] To: pentax-discuss@pdml.net Sent: Sunday, January 09, 2005 7:40 PM Subject: Re: Sigma 2.8 Zoom lens comments The comments so far do not surprise me much. It was just an idea I had :) I'm hoping someone that has used one of these zooms will chime in in the next few days. My money might be better spent picking up some fast primes, AF or M.
Re: Sigma 2.8 Zoom lens comments
William Robb wrote; In my case, I think a slower lens would only make the AF performance worse than the useless that it already is. That's pretty much what I was saying. It stands to reason that a fast lens would improve autofocus performance. Joe says no. Paul In my case, I think a slower lens would only make the AF performance worse than the useless that it already is. William Robb
Re: Sigma 2.8 Zoom lens comments
Hmmm getting correctly focused images pretty much all the time doesn't sound so good. Getting correctly focused images all the time sounds a lot better. Can't help but wonder how much of a role DOF plays in your correctly focused images. I'd be interested to know how well the focus looks at wider apertures, like 2.0. That would seem to be a better indication of how well the camera is focusing. Just ca;ll me an old fashioned skeptic ;-)) Shel [Original Message] From: Herb Chong [EMAIL PROTECTED] i read about this slow or useless AF performance in low light on the *istD comment and i wonder every time what is really going on. i shoot a lot of waterfall shots with a 10 stop ND filter mounted. that gives me typically 8 second exposures at f11 or f13 at ISO 200. i set the camera to point select AF mode, choose a focus point, press the shutter release half way, it focuses and lock correctly (usually on the first try), and i take my picture. the 10 stop filter is mounted while i am doing this. it's almost impossible to see *anything* in the viewfinder except the readouts, yet the AF works and i get correctly focused images pretty much all the time.
Re: Sigma 2.8 Zoom lens comments
I was thinking the same thing. At f11, depth of field helps a lot. I love my *istD, but in low-light, autofocus is definitely not accurate. I can't imagine even attempting it with a 10 stop ND. I think I would focus manually and then screw the filter on. Paul Hmmm getting correctly focused images pretty much all the time doesn't sound so good. Getting correctly focused images all the time sounds a lot better. Can't help but wonder how much of a role DOF plays in your correctly focused images. I'd be interested to know how well the focus looks at wider apertures, like 2.0. That would seem to be a better indication of how well the camera is focusing. Just ca;ll me an old fashioned skeptic ;-)) Shel [Original Message] From: Herb Chong [EMAIL PROTECTED] i read about this slow or useless AF performance in low light on the *istD comment and i wonder every time what is really going on. i shoot a lot of waterfall shots with a 10 stop ND filter mounted. that gives me typically 8 second exposures at f11 or f13 at ISO 200. i set the camera to point select AF mode, choose a focus point, press the shutter release half way, it focuses and lock correctly (usually on the first try), and i take my picture. the 10 stop filter is mounted while i am doing this. it's almost impossible to see *anything* in the viewfinder except the readouts, yet the AF works and i get correctly focused images pretty much all the time.
Re: Sigma 2.8 Zoom lens comments
- Original Message - From: Herb Chong Subject: Re: Sigma 2.8 Zoom lens comments i read about this slow or useless AF performance in low light on the *istD comment and i wonder every time what is really going on. i shoot a lot of waterfall shots with a 10 stop ND filter mounted. that gives me typically 8 second exposures at f11 or f13 at ISO 200. i set the camera to point select AF mode, choose a focus point, press the shutter release half way, it focuses and lock correctly (usually on the first try), and i take my picture. the 10 stop filter is mounted while i am doing this. it's almost impossible to see *anything* in the viewfinder except the readouts, yet the AF works and i get correctly focused images pretty much all the time. I tend to shoot moving subjects with the istD. In low light I can do the focus better myself. I still do my landscapes on a 4x5. Every one is correctly focussed G. William Robb
Re: Sigma 2.8 Zoom lens comments
- Original Message - From: [EMAIL PROTECTED] Subject: Re: Sigma 2.8 Zoom lens comments William Robb wrote; In my case, I think a slower lens would only make the AF performance worse than the useless that it already is. That's pretty much what I was saying. It stands to reason that a fast lens would improve autofocus performance. Joe says no. HAR!! Caught ya with an additive negative. Reread that sentence very slowly. b...
Re: Sigma 2.8 Zoom lens comments
Joseph Tainter mused: Poor autofocus performance in low light is a characteristic of the *ist D. A faster lens will not help. In low light with my FA 50 f1.7 on the D, autofocus is slow to impossible. How low do you need? I was shooting last night with an F50/f1.7 on my *ist-D, ISO 800, recommended epxosure 1/[EMAIL PROTECTED], and autofocus was fast, responsive, and accurate. I lost several shots because of motion of the subjects, and several more because of camera shake, but none caused by AF problems. I filled 1GB with RAW images, so that's around 70 shots in total.
