Re: Another k10D problem
Hello David, Contacted pentaxusa - they could not access the flickr pictures. Suggested I send the camera back in. Ick. Please inform us about the conclusions when you get your camera back. Yes the flickr is tricky for some..:) www.skiboy.com/fiso/italianflagmodeDave.jpg (172k) I am still interested in any speculation and possible attempts of others to duplicate this. Tried again today. Nothing like yours. (My slowest speed is 1/2 s @ 1600 iso and f32) www.skiboy.com/fiso/italianflagmode1.jpg (205k) -- Best regards, Fiso, the guy with too much spare time :) mailto:[EMAIL PROTECTED] -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net
Re: Another k10D problem
Hello David, http://www.flickr.com/photos/[EMAIL PROTECTED]/ This is a series of pictures of a white piece of tissue used to wrap a Christmas gift. Light was natural, white balance manually set. Updated firmware. Obviously, many of these are 1 or 2 stops underexposed, but, I was startled at the bands of color (green to the left, magenta to the right). I have tried everything to produce the artefacts you got, but no luck...:) The 'best' two: (165k) www.skiboy.com/fiso/underexpos1.jpg k10d, supertak M 1.8/55 iso 100 normal daylight through the window, underexposed. Or with iso 1600, all the same settings: (195k) www.skiboy.com/fiso/underexpos2.jpg -- Best regards, Fiso mailto:[EMAIL PROTECTED] -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net
Re: Another k10D problem or just an old one?
I'm with Godders on this one... Maybe something to do with the type of window. For example, argon gas between the panes or a UV (or some other insulating filter) on the glass could cause weird colors that may otherwise not be noticed by your eyes. Better to test outdoors in real natural light. -- Christian http://photography.skofteland.net Godfrey DiGiorgi wrote: Hmm. I would be inclined to think that there's some odd refraction happening through the window which is not visible to the eye. I understand the captures are well-underexposed, that would exacerbate the appearance of the rainbow. Test with other lighting ... particularly one in which there is no glass in the light path. G On Jan 30, 2007, at 6:53 PM, David Weiss wrote: Godfrey, As to your questions below: Light source was sunlight through the window. With the amount of snow on the ground, a lot of that light was reflected sunlight. I adjusted the white balance manually and it seemed fine. I am going to check it again with other light sources and some other subjects and without underexposure. No filters used or hood, but light was at my back so no light entering lens at oblique angles. Thanks for the reply. I sent a note to pentax USA, referring them to my images. Hope they take a look. Dave -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net
Re: Another k10D problem or just an old one?
I think its in Italian flag mode, did you get the K10D World cup edition or something? [EMAIL PROTECTED] wrote: Hello, Well, the other day I decided to take a look at this k lens underexposure issue (which appears to be a real problem) and instead found another problem. Here are the pictures: http://www.flickr.com/photos/[EMAIL PROTECTED]/ This is a series of pictures of a white piece of tissue used to wrap a Christmas gift. Light was natural, white balance manually set. Updated firmware. Obviously, many of these are 1 or 2 stops underexposed, but, I was startled at the bands of color (green to the left, magenta to the right). Photos 1-3: Three is probably close to being exposed properly, but it still has a hint of the problem. The others show it clearly. Photos 4-6: So I decided to look at photos that were overexposed at different f stops. I don't see the problem in 4 and 5, but it shows up again in 6. Photos 7-9: So I thought to change lenses. Still there on 9, small aperture again. Photo 10: Might as well check the problem at 400 sensitivity. A hint of the problem. Photo 11: There it is again. Seems that the combination of high sensitivity, small aperture and underexposure causes the problem. I also tried RAW and normal instead of bright mode, this did not cause the problem to be eliminated. So, is this just the infamous banding problem magnified a bit? Is this just my camera? I hope someone can verify for me that this is just a characteristic of this camera. Not that this would thrill me, because I expect something to work properly, but at least I wouldn't send my camera in again. I know that I am not likely to shoot under these conditions, but it would be nice if the camera worked properly just the same. Dave -- Someone handed me a picture and said, This is a picture of me when I was younger. Every picture of you is when you were younger. ...Here's a picture of me when I'm older. Where'd you get that camera man? - Mitch Hedberg -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net
Re: Another k10D problem or just an old one?
Mark! David Weis wrote: Wow, I thought people on this list could curb the sarcasm and help a person. Tom C. From: David Weiss [EMAIL PROTECTED] Reply-To: Pentax-Discuss Mail List pdml@pdml.net To: Pentax-Discuss Mail List pdml@pdml.net Subject: Re: Another k10D problem or just an old one? Date: Tue, 30 Jan 2007 21:32:12 -0500 Paul Stenquist wrote: He's shooting jpegs on bright setting and underexposing by two to three stops. How can you conclude it's not normal? Wow, I thought people on this list could curb the sarcasm and help a person. Is that beyond everyone these days? I said this problem showed up on RAW photos as well. The problem is evident on picture number 3, which is clearly not underexposed. This problem showed up on non-white subjects. What am I not saying correctly? I just wanted to know if it is a normal for this camera to do this under such conditions, that is all I wanted to know. I wasn't calling it a bad camera or anything else. Geez. Dave Paul On Jan 30, 2007, at 8:53 PM, Digital Image Studio wrote: On 31/01/07, David Weiss [EMAIL PROTECTED] wrote: So, is this just the infamous banding problem magnified a bit? No it's not banding but neither is it normal nor should it have to be tolerated. I would suggest that you pose the question to Pentax and send links to select images, ask them how to remedy the problem and if they can't solve it then have your camera swapped for a new one. -- Rob Studdert HURSTVILLE AUSTRALIA Tel +61-2-9554-4110 UTC(GMT) +10 Hours [EMAIL PROTECTED] http://home.swiftdsl.com.au/~distudio//publications/ Pentax user since 1986, PDMLer since 1998 -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net
Re: Another k10D problem or just an old one?
Gonz wrote: I think its in Italian flag mode, did you get the K10D World cup edition or something? Mark! -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net
Re: Another k10D problem or just an old one?
Christian wrote: I'm with Godders on this one... Maybe something to do with the type of window. For example, argon gas between the panes or a UV (or some other insulating filter) on the glass could cause weird colors that may otherwise not be noticed by your eyes. Better to test outdoors in real natural light. Good idea, but I just went outside and reproduced the colors outside. I went outside and tested the k10d with a fa50f1.4. I shot a brickwall, natural tone jpegs. This was to correct some potential problems as posed by the list yesterday, that is, problems caused by light going through window material and shooting of a white object. First I tested at different speeds, in groups of three, normal, 1 stop under, 2 stops under. Let the lens open up to f4 or f4.5 and varied the shutter speed. Pic's 1-3: 1/8 sec, f4, 100 speed. normal exposure. Underexposed by slowing the shutter by 1 and 2 stops. No color shifts. Pic's 4-6: Repeated of above, except start at 1/15s, f4, 400 speed. No shifting for any of the 3. Pic's 7-9: Similar test at 800 speed. No problems. Pic's 10-12: Repeat for 1/30s, f4.5, 1600 speed. Looks okay. Then I decided to try things that were near what I did yesterday. That is, high sensitivity, long exposure (greater than 1/4s) and small f stops (f22). Pic's 13-15: Repeat situation above starting at .5s, f22, 1600 speed. There it is again, green and magenta. Specially so in the first (normal exposure) and the 1 stop under exposure. Pic's 16-18: 1 sec f22, 800 speed. Same problem as above for first two pictures especially, but not as strongly as the one's at 1600. Then I decided to see if long exposure and small f stops will produce the color shifting at other sensitivities. Pic's 19: 2 sec, f22, 400 speed. Still there, but not strongly. Pic 20: 4 sec, f22, still there, although getting to the point where it is difficult to tell. Pic 21: 2 sec, f22, 200 speed. Still there. Very Faint. So, my conclusions for MY CAMERA (do not know about other k10d's): 1. Color shift will be produced at any sensitivity, during underexposure or normal exposure, if both the shutter speed is long and the f stop is small. 2. At conditions as described in number 1, color shifting is maximized at higher sensitivity and a stop of underexposure. Normal exposures at lower sensitivities minimize the effect. 3. Camera is capable of images without any color shifting at all light sensitivities, even with underexposure if conditions in number 1 are not met. I am beginning to think it is just a limit of the technology. I would bet that others could reproduce this result. On the other hand, I am surprised that someone else has not bumped into this problem. I am convinced that it is not the light source or lens. Could just be the unusual conditions or just my camera. Cannot say unless some others are willing to give it a go. Godfrey (or anyone else), if you are willing, could you try a long exposure, small f stop at a high sensitivity? I posted 6 of these on flickr. 10,11,12 look fine (shot as described above), 13,14,15 show the shifting (shot as described above). If someone would like me to post any others, I could do that. http://www.flickr.com/photos/[EMAIL PROTECTED]/?savedsettings=375990192#photo375990192 Contacted pentaxusa - they could not access the flickr pictures. Suggested I send the camera back in. Ick. I am still interested in any speculation and possible attempts of others to duplicate this. Thanks for your time and patience, Dave x -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net
Re: Another k10D problem
Fiso, Thanks for the efforts. Please have a look at my other recent post to see my latest findings. Seems that the combination of long shutter speed, small f stop, high light sensitivity and some underexposure will do it. If this is just my camera, well you are indeed more lucky than I am. Dave Fiso_PENTAX wrote: Hello David, http://www.flickr.com/photos/[EMAIL PROTECTED]/ This is a series of pictures of a white piece of tissue used to wrap a Christmas gift. Light was natural, white balance manually set. Updated firmware. Obviously, many of these are 1 or 2 stops underexposed, but, I was startled at the bands of color (green to the left, magenta to the right). I have tried everything to produce the artefacts you got, but no luck...:) The 'best' two: (165k) www.skiboy.com/fiso/underexpos1.jpg k10d, supertak M 1.8/55 iso 100 normal daylight through the window, underexposed. Or with iso 1600, all the same settings: (195k) www.skiboy.com/fiso/underexpos2.jpg -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net
Re: Another k10D problem or just an old one?
Couldn't find any situations where I could get longer than about .2 seconds exposure at f/22 with the ISO set to 1600. I found that if I exposed at 3 stops under normal exposure, the camera's sensitivity ran seriously to the blue channel at that point, but the entire field went bluish, no green-magenta banding. The blue-channel predominance was much less at ISO 100. Let Pentax take care of it. Something's weird with your camera. Godfrey On Jan 31, 2007, at 4:44 PM, David Weiss wrote: Good idea, but I just went outside and reproduced the colors outside. I went outside and tested the k10d with a fa50f1.4. I shot a brickwall, natural tone jpegs. This was to correct some potential problems as posed by the list yesterday, that is, problems caused by light going through window material and shooting of a white object. First I tested at different speeds, in groups of three, normal, 1 stop under, 2 stops under. Let the lens open up to f4 or f4.5 and varied the shutter speed. Pic's 1-3: 1/8 sec, f4, 100 speed. normal exposure. Underexposed by slowing the shutter by 1 and 2 stops. No color shifts. Pic's 4-6: Repeated of above, except start at 1/15s, f4, 400 speed. No shifting for any of the 3. Pic's 7-9: Similar test at 800 speed. No problems. Pic's 10-12: Repeat for 1/30s, f4.5, 1600 speed. Looks okay. Then I decided to try things that were near what I did yesterday. That is, high sensitivity, long exposure (greater than 1/4s) and small f stops (f22). Pic's 13-15: Repeat situation above starting at .5s, f22, 1600 speed. There it is again, green and magenta. Specially so in the first (normal exposure) and the 1 stop under exposure. Pic's 16-18: 1 sec f22, 800 speed. Same problem as above for first two pictures especially, but not as strongly as the one's at 1600. Then I decided to see if long exposure and small f stops will produce the color shifting at other sensitivities. Pic's 19: 2 sec, f22, 400 speed. Still there, but not strongly. Pic 20: 4 sec, f22, still there, although getting to the point where it is difficult to tell. Pic 21: 2 sec, f22, 200 speed. Still there. Very Faint. So, my conclusions for MY CAMERA (do not know about other k10d's): 1. Color shift will be produced at any sensitivity, during underexposure or normal exposure, if both the shutter speed is long and the f stop is small. 2. At conditions as described in number 1, color shifting is maximized at higher sensitivity and a stop of underexposure. Normal exposures at lower sensitivities minimize the effect. 3. Camera is capable of images without any color shifting at all light sensitivities, even with underexposure if conditions in number 1 are not met. I am beginning to think it is just a limit of the technology. I would bet that others could reproduce this result. On the other hand, I am surprised that someone else has not bumped into this problem. I am convinced that it is not the light source or lens. Could just be the unusual conditions or just my camera. Cannot say unless some others are willing to give it a go. Godfrey (or anyone else), if you are willing, could you try a long exposure, small f stop at a high sensitivity? I posted 6 of these on flickr. 10,11,12 look fine (shot as described above), 13,14,15 show the shifting (shot as described above). If someone would like me to post any others, I could do that. http://www.flickr.com/photos/[EMAIL PROTECTED]/? savedsettings=375990192#photo375990192 Contacted pentaxusa - they could not access the flickr pictures. Suggested I send the camera back in. Ick. I am still interested in any speculation and possible attempts of others to duplicate this. Thanks for your time and patience, Dave x -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net
Another k10D problem or just an old one?
Hello, Well, the other day I decided to take a look at this k lens underexposure issue (which appears to be a real problem) and instead found another problem. Here are the pictures: http://www.flickr.com/photos/[EMAIL PROTECTED]/ This is a series of pictures of a white piece of tissue used to wrap a Christmas gift. Light was natural, white balance manually set. Updated firmware. Obviously, many of these are 1 or 2 stops underexposed, but, I was startled at the bands of color (green to the left, magenta to the right). Photos 1-3: Three is probably close to being exposed properly, but it still has a hint of the problem. The others show it clearly. Photos 4-6: So I decided to look at photos that were overexposed at different f stops. I don't see the problem in 4 and 5, but it shows up again in 6. Photos 7-9: So I thought to change lenses. Still there on 9, small aperture again. Photo 10: Might as well check the problem at 400 sensitivity. A hint of the problem. Photo 11: There it is again. Seems that the combination of high sensitivity, small aperture and underexposure causes the problem. I also tried RAW and normal instead of bright mode, this did not cause the problem to be eliminated. So, is this just the infamous banding problem magnified a bit? Is this just my camera? I hope someone can verify for me that this is just a characteristic of this camera. Not that this would thrill me, because I expect something to work properly, but at least I wouldn't send my camera in again. I know that I am not likely to shoot under these conditions, but it would be nice if the camera worked properly just the same. Dave -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net
Re: Another k10D problem or just an old one?
Don't know what's going on here, but grossly underexposed pictures, which almost all of these are, will not yield good results. I also think shooting white with the jpeg bright setting might be somewhat of a problem. I think it's possible to generate bad results with any camera if one works hard enough to achieve them. Some of my underexposed transparencies from my Speed Graphic were real clunkers. Paul On Jan 30, 2007, at 7:00 PM, David Weiss wrote: Hello, Well, the other day I decided to take a look at this k lens underexposure issue (which appears to be a real problem) and instead found another problem. Here are the pictures: http://www.flickr.com/photos/[EMAIL PROTECTED]/ This is a series of pictures of a white piece of tissue used to wrap a Christmas gift. Light was natural, white balance manually set. Updated firmware. Obviously, many of these are 1 or 2 stops underexposed, but, I was startled at the bands of color (green to the left, magenta to the right). Photos 1-3: Three is probably close to being exposed properly, but it still has a hint of the problem. The others show it clearly. Photos 4-6: So I decided to look at photos that were overexposed at different f stops. I don't see the problem in 4 and 5, but it shows up again in 6. Photos 7-9: So I thought to change lenses. Still there on 9, small aperture again. Photo 10: Might as well check the problem at 400 sensitivity. A hint of the problem. Photo 11: There it is again. Seems that the combination of high sensitivity, small aperture and underexposure causes the problem. I also tried RAW and normal instead of bright mode, this did not cause the problem to be eliminated. So, is this just the infamous banding problem magnified a bit? Is this just my camera? I hope someone can verify for me that this is just a characteristic of this camera. Not that this would thrill me, because I expect something to work properly, but at least I wouldn't send my camera in again. I know that I am not likely to shoot under these conditions, but it would be nice if the camera worked properly just the same. Dave -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net
Re: Another k10D problem or just an old one?
BTW, I shoot with K lenses quite frequently. No problem. A couple of recent examples: http://www.photo.net/photodb/photo?photo_id=5458250size=lg http://www.photo.net/photodb/photo?photo_id=5458281size=lg On Jan 30, 2007, at 7:00 PM, David Weiss wrote: Hello, Well, the other day I decided to take a look at this k lens underexposure issue (which appears to be a real problem) and instead found another problem. Here are the pictures: http://www.flickr.com/photos/[EMAIL PROTECTED]/ This is a series of pictures of a white piece of tissue used to wrap a Christmas gift. Light was natural, white balance manually set. Updated firmware. Obviously, many of these are 1 or 2 stops underexposed, but, I was startled at the bands of color (green to the left, magenta to the right). Photos 1-3: Three is probably close to being exposed properly, but it still has a hint of the problem. The others show it clearly. Photos 4-6: So I decided to look at photos that were overexposed at different f stops. I don't see the problem in 4 and 5, but it shows up again in 6. Photos 7-9: So I thought to change lenses. Still there on 9, small aperture again. Photo 10: Might as well check the problem at 400 sensitivity. A hint of the problem. Photo 11: There it is again. Seems that the combination of high sensitivity, small aperture and underexposure causes the problem. I also tried RAW and normal instead of bright mode, this did not cause the problem to be eliminated. So, is this just the infamous banding problem magnified a bit? Is this just my camera? I hope someone can verify for me that this is just a characteristic of this camera. Not that this would thrill me, because I expect something to work properly, but at least I wouldn't send my camera in again. I know that I am not likely to shoot under these conditions, but it would be nice if the camera worked properly just the same. Dave -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net
Re: Another k10D problem or just an old one?
Which lens is that Paul? Very nice ice pictures, btw. Dave Paul Stenquist wrote: BTW, I shoot with K lenses quite frequently. No problem. A couple of recent examples: http://www.photo.net/photodb/photo?photo_id=5458250size=lg http://www.photo.net/photodb/photo?photo_id=5458281size=lg On Jan 30, 2007, at 7:00 PM, David Weiss wrote: Hello, Well, the other day I decided to take a look at this k lens underexposure issue (which appears to be a real problem) and instead found another problem. Here are the pictures: http://www.flickr.com/photos/[EMAIL PROTECTED]/ This is a series of pictures of a white piece of tissue used to wrap a Christmas gift. Light was natural, white balance manually set. Updated firmware. Obviously, many of these are 1 or 2 stops underexposed, but, I was startled at the bands of color (green to the left, magenta to the right). Photos 1-3: Three is probably close to being exposed properly, but it still has a hint of the problem. The others show it clearly. Photos 4-6: So I decided to look at photos that were overexposed at different f stops. I don't see the problem in 4 and 5, but it shows up again in 6. Photos 7-9: So I thought to change lenses. Still there on 9, small aperture again. Photo 10: Might as well check the problem at 400 sensitivity. A hint of the problem. Photo 11: There it is again. Seems that the combination of high sensitivity, small aperture and underexposure causes the problem. I also tried RAW and normal instead of bright mode, this did not cause the problem to be eliminated. So, is this just the infamous banding problem magnified a bit? Is this just my camera? I hope someone can verify for me that this is just a characteristic of this camera. Not that this would thrill me, because I expect something to work properly, but at least I wouldn't send my camera in again. I know that I am not likely to shoot under these conditions, but it would be nice if the camera worked properly just the same. Dave -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net
Re: Another k10D problem or just an old one?
Paul Stenquist wrote: Don't know what's going on here, but grossly underexposed pictures, I know, but once I found the problem to be seen more clearly when underexposed, I just left it that way. Wouldn't this just mimic shadow areas in a well exposed photo? which almost all of these are, will not yield good results. I also I know, but colored bands? That just doesn't seem right to me. I guess I would be more tolerant of other problems that you might see with film, this just seems like a defect in the design. Or maybe I am just old fashion in my thinking. think shooting white with the jpeg bright setting might be somewhat of a problem. I think it's possible to generate bad results with any camera if one works hard enough to achieve them. Some of my underexposed transparencies from my Speed Graphic were real clunkers. I know, I have had my share of clunkers too, just I understood why in those cases. Could someone see if they could reproduce these weird results so I can stop thinking about sending my new camera back to Colorado? Do you think that this is just that banding issue? Seems like it is happening in the same conditions. Dave Paul On Jan 30, 2007, at 7:00 PM, David Weiss wrote: Hello, Well, the other day I decided to take a look at this k lens underexposure issue (which appears to be a real problem) and instead found another problem. Here are the pictures: http://www.flickr.com/photos/[EMAIL PROTECTED]/ This is a series of pictures of a white piece of tissue used to wrap a Christmas gift. Light was natural, white balance manually set. Updated firmware. Obviously, many of these are 1 or 2 stops underexposed, but, I was startled at the bands of color (green to the left, magenta to the right). Photos 1-3: Three is probably close to being exposed properly, but it still has a hint of the problem. The others show it clearly. Photos 4-6: So I decided to look at photos that were overexposed at different f stops. I don't see the problem in 4 and 5, but it shows up again in 6. Photos 7-9: So I thought to change lenses. Still there on 9, small aperture again. Photo 10: Might as well check the problem at 400 sensitivity. A hint of the problem. Photo 11: There it is again. Seems that the combination of high sensitivity, small aperture and underexposure causes the problem. I also tried RAW and normal instead of bright mode, this did not cause the problem to be eliminated. So, is this just the infamous banding problem magnified a bit? Is this just my camera? I hope someone can verify for me that this is just a characteristic of this camera. Not that this would thrill me, because I expect something to work properly, but at least I wouldn't send my camera in again. I know that I am not likely to shoot under these conditions, but it would be nice if the camera worked properly just the same. Dave -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net
Re: Another k10D problem or just an old one?
It's not banding. It seems to be due to a combination of things. Do you have your jpeg settings at highly saturated as well as bright? Underexposing white doesn't give you the same thing you would get shooting normal shadow detail at a correct exposre. How well does your camera take real photographs? I don't see any benefit in trying to create weird results by shooting things one would never shoot. An all white surface should be overexposed 1.5 to 2.5 stops to get normal results. Your meter thinks everything is 18% gray. Meters are dumb. Photographers have to provide the intelligence. I suspect that these results are a combination of your jpeg settings and the underexposure. Lets see some of your properly exposed photographs. Then we can see if there is any problem with your camera. Paul On Jan 30, 2007, at 7:49 PM, David Weiss wrote: Paul Stenquist wrote: Don't know what's going on here, but grossly underexposed pictures, I know, but once I found the problem to be seen more clearly when underexposed, I just left it that way. Wouldn't this just mimic shadow areas in a well exposed photo? which almost all of these are, will not yield good results. I also I know, but colored bands? That just doesn't seem right to me. I guess I would be more tolerant of other problems that you might see with film, this just seems like a defect in the design. Or maybe I am just old fashion in my thinking. think shooting white with the jpeg bright setting might be somewhat of a problem. I think it's possible to generate bad results with any camera if one works hard enough to achieve them. Some of my underexposed transparencies from my Speed Graphic were real clunkers. I know, I have had my share of clunkers too, just I understood why in those cases. Could someone see if they could reproduce these weird results so I can stop thinking about sending my new camera back to Colorado? Do you think that this is just that banding issue? Seems like it is happening in the same conditions. Dave Paul On Jan 30, 2007, at 7:00 PM, David Weiss wrote: Hello, Well, the other day I decided to take a look at this k lens underexposure issue (which appears to be a real problem) and instead found another problem. Here are the pictures: http://www.flickr.com/photos/[EMAIL PROTECTED]/ This is a series of pictures of a white piece of tissue used to wrap a Christmas gift. Light was natural, white balance manually set. Updated firmware. Obviously, many of these are 1 or 2 stops underexposed, but, I was startled at the bands of color (green to the left, magenta to the right). Photos 1-3: Three is probably close to being exposed properly, but it still has a hint of the problem. The others show it clearly. Photos 4-6: So I decided to look at photos that were overexposed at different f stops. I don't see the problem in 4 and 5, but it shows up again in 6. Photos 7-9: So I thought to change lenses. Still there on 9, small aperture again. Photo 10: Might as well check the problem at 400 sensitivity. A hint of the problem. Photo 11: There it is again. Seems that the combination of high sensitivity, small aperture and underexposure causes the problem. I also tried RAW and normal instead of bright mode, this did not cause the problem to be eliminated. So, is this just the infamous banding problem magnified a bit? Is this just my camera? I hope someone can verify for me that this is just a characteristic of this camera. Not that this would thrill me, because I expect something to work properly, but at least I wouldn't send my camera in again. I know that I am not likely to shoot under these conditions, but it would be nice if the camera worked properly just the same. Dave -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net
Re: Another k10D problem or just an old one?
Thanks David. It's the SMC Pentax 85/1.8. I also use the SMC Pentax 135/2.5 quite a bit. Paul On Jan 30, 2007, at 7:43 PM, David Weiss wrote: Which lens is that Paul? Very nice ice pictures, btw. Dave Paul Stenquist wrote: BTW, I shoot with K lenses quite frequently. No problem. A couple of recent examples: http://www.photo.net/photodb/photo?photo_id=5458250size=lg http://www.photo.net/photodb/photo?photo_id=5458281size=lg On Jan 30, 2007, at 7:00 PM, David Weiss wrote: Hello, Well, the other day I decided to take a look at this k lens underexposure issue (which appears to be a real problem) and instead found another problem. Here are the pictures: http://www.flickr.com/photos/[EMAIL PROTECTED]/ This is a series of pictures of a white piece of tissue used to wrap a Christmas gift. Light was natural, white balance manually set. Updated firmware. Obviously, many of these are 1 or 2 stops underexposed, but, I was startled at the bands of color (green to the left, magenta to the right). Photos 1-3: Three is probably close to being exposed properly, but it still has a hint of the problem. The others show it clearly. Photos 4-6: So I decided to look at photos that were overexposed at different f stops. I don't see the problem in 4 and 5, but it shows up again in 6. Photos 7-9: So I thought to change lenses. Still there on 9, small aperture again. Photo 10: Might as well check the problem at 400 sensitivity. A hint of the problem. Photo 11: There it is again. Seems that the combination of high sensitivity, small aperture and underexposure causes the problem. I also tried RAW and normal instead of bright mode, this did not cause the problem to be eliminated. So, is this just the infamous banding problem magnified a bit? Is this just my camera? I hope someone can verify for me that this is just a characteristic of this camera. Not that this would thrill me, because I expect something to work properly, but at least I wouldn't send my camera in again. I know that I am not likely to shoot under these conditions, but it would be nice if the camera worked properly just the same. Dave -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net
Re: Another k10D problem or just an old one?
On 31/01/07, David Weiss [EMAIL PROTECTED] wrote: So, is this just the infamous banding problem magnified a bit? No it's not banding but neither is it normal nor should it have to be tolerated. I would suggest that you pose the question to Pentax and send links to select images, ask them how to remedy the problem and if they can't solve it then have your camera swapped for a new one. -- Rob Studdert HURSTVILLE AUSTRALIA Tel +61-2-9554-4110 UTC(GMT) +10 Hours [EMAIL PROTECTED] http://home.swiftdsl.com.au/~distudio//publications/ Pentax user since 1986, PDMLer since 1998 -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net
Re: Another k10D problem or just an old one?
He's shooting jpegs on bright setting and underexposing by two to three stops. How can you conclude it's not normal? Paul On Jan 30, 2007, at 8:53 PM, Digital Image Studio wrote: On 31/01/07, David Weiss [EMAIL PROTECTED] wrote: So, is this just the infamous banding problem magnified a bit? No it's not banding but neither is it normal nor should it have to be tolerated. I would suggest that you pose the question to Pentax and send links to select images, ask them how to remedy the problem and if they can't solve it then have your camera swapped for a new one. -- Rob Studdert HURSTVILLE AUSTRALIA Tel +61-2-9554-4110 UTC(GMT) +10 Hours [EMAIL PROTECTED] http://home.swiftdsl.com.au/~distudio//publications/ Pentax user since 1986, PDMLer since 1998 -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net
Re: Another k10D problem or just an old one?
Paul Stenquist wrote: It's not banding. It seems to be due to a combination of things. Do you have your jpeg settings at highly saturated as well as bright? No. I saw the same problem on RAW images and the non-bright setting. The saturation is at normal. Underexposing white doesn't give you the same thing you would get shooting normal shadow detail at a correct exposre. How well does your camera take real photographs? I don't see any benefit in trying to create weird results by shooting things one would never shoot. An all white surface should be overexposed 1.5 to 2.5 stops to get normal results. I know, like I said, I just thought it showed up better this way. If you look at photo 3, that one is about exposed right, maybe a bit overexposed, and it still has the color problem. It isn't as pronounced, but it is there. Your meter thinks everything is 18% gray. Meters are dumb. Photographers have to provide the intelligence. I suspect that these results are a combination of your jpeg settings and the underexposure. Lets see some of your properly exposed photographs. I will take some new ones tomorrow and post. Not a problem, in general. I just got this camera from Pentax USA as a replacement for my first k10D. Weather has not allowed a lot of outside work. I did not want the flash to be a possible source of this color problem, so do not want to take any pictures inside right now. It is just my opinion, but I should think that this should never happen, regardless of the set-up. Even in photo 3 and 10, which is somewhat normal (1/10s, f13, 400), the problem is there. The first set of photos I noticed this did not have any strong white objects, a lot of green carpet and brown blanket chest. It would help me if I knew if anyone else has a camera that acts this way. Dave -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net
Re: Another k10D problem or just an old one?
- Original Message - From: David Weiss Subject: Another k10D problem or just an old one? I know that I am not likely to shoot under these conditions, but it would be nice if the camera worked properly just the same. You get reciprocity failure with film, why not with digital? Almost every time I see a problem with digital, it is the same type of scene. Someone takes an evenly lit white object, underexposes it 4 or so stops by stopping the lens way down, and then finds a problem. The technology ain't perfect, but at least you aren't whining about scratched negatives and lousy processing. William Robb -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net
Re: Another k10D problem or just an old one?
Paul Stenquist wrote: He's shooting jpegs on bright setting and underexposing by two to three stops. How can you conclude it's not normal? Wow, I thought people on this list could curb the sarcasm and help a person. Is that beyond everyone these days? I said this problem showed up on RAW photos as well. The problem is evident on picture number 3, which is clearly not underexposed. This problem showed up on non-white subjects. What am I not saying correctly? I just wanted to know if it is a normal for this camera to do this under such conditions, that is all I wanted to know. I wasn't calling it a bad camera or anything else. Geez. Dave Paul On Jan 30, 2007, at 8:53 PM, Digital Image Studio wrote: On 31/01/07, David Weiss [EMAIL PROTECTED] wrote: So, is this just the infamous banding problem magnified a bit? No it's not banding but neither is it normal nor should it have to be tolerated. I would suggest that you pose the question to Pentax and send links to select images, ask them how to remedy the problem and if they can't solve it then have your camera swapped for a new one. -- Rob Studdert HURSTVILLE AUSTRALIA Tel +61-2-9554-4110 UTC(GMT) +10 Hours [EMAIL PROTECTED] http://home.swiftdsl.com.au/~distudio//publications/ Pentax user since 1986, PDMLer since 1998 -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net
Re: Another k10D problem or just an old one?
William Robb wrote: - Original Message - From: David Weiss Subject: Another k10D problem or just an old one? I know that I am not likely to shoot under these conditions, but it would be nice if the camera worked properly just the same. You get reciprocity failure with film, why not with digital? Almost every time I see a problem with digital, it is the same type of scene. Someone takes an evenly lit white object, underexposes it 4 or so stops by stopping the lens way down, and then finds a problem. The technology ain't perfect, but at least you aren't whining about scratched negatives and lousy processing. William Robb William, Like I said, if this is just a fault of the technology, while I would like it to be perfect, I could live with it. I am just trying to gather information and make a rational decision on whether this is a quirk of the particular camera in my hands so that I might know if I should send it in. The problem might be symptomatic of some larger problem with this particular camera. I should think a new camera (less than 10 days in my hands) should operate as intended. Again, as far as only showing problems if underexposed by 4 stops as you say, I can clearly point to my photo marked 3 as not being underexposed but yet showing the problem. And I clearly say that I am not likely to shoot often at 1600, especially at small f stops, but I still think it should operate correctly (that is, as any other example of the camera operates). Dave Dave -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net
Re: Another k10D problem or just an old one?
On Jan 30, 2007, at 4:00 PM, David Weiss wrote: So, is this just the infamous banding problem magnified a bit? No. Is this just my camera? I hope someone can verify for me that this is just a characteristic of this camera. Not that this would thrill me, because I expect something to work properly, but at least I wouldn't send my camera in again. I know that I am not likely to shoot under these conditions, but it would be nice if the camera worked properly just the same. No idea what's going on in these pictures. My K10D does not produce anything of the sort nor can I make it happen. What is the light source? You say it is natural light ... is it coming through a window? at an angle? Does it happen in any other lighting circumstances? Do you have UV or other filters on these lenses? Do you have lens hoods on them? G -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net
Re: Another k10D problem or just an old one?
I'm not being sarcastic. I didn't see the RAW images. If they were underexposed as badly as the jpegs, I wouldn't be surprised to see color appearing on white. I'm sorry if I wasn't helpful. You may have a problem. But as I said, it would be easier to tell with correct exposures and a normal range of tones. Your examples caused my scepticism. Sorry if I offended you. You may have a problem. Let's see some more examples. It's certainly not normal for the camera to produce color bands under standard or even somewhat extreme conditions. Can you shot a color scale card and a gray scale card in open shade? That could be revealing. You might also shoot something of a general neutral tone -- something close to medium gray or light brown-- in even light. Paul On Jan 30, 2007, at 9:32 PM, David Weiss wrote: Paul Stenquist wrote: He's shooting jpegs on bright setting and underexposing by two to three stops. How can you conclude it's not normal? Wow, I thought people on this list could curb the sarcasm and help a person. Is that beyond everyone these days? I said this problem showed up on RAW photos as well. The problem is evident on picture number 3, which is clearly not underexposed. This problem showed up on non-white subjects. What am I not saying correctly? I just wanted to know if it is a normal for this camera to do this under such conditions, that is all I wanted to know. I wasn't calling it a bad camera or anything else. Geez. Dave Paul On Jan 30, 2007, at 8:53 PM, Digital Image Studio wrote: On 31/01/07, David Weiss [EMAIL PROTECTED] wrote: So, is this just the infamous banding problem magnified a bit? No it's not banding but neither is it normal nor should it have to be tolerated. I would suggest that you pose the question to Pentax and send links to select images, ask them how to remedy the problem and if they can't solve it then have your camera swapped for a new one. -- Rob Studdert HURSTVILLE AUSTRALIA Tel +61-2-9554-4110 UTC(GMT) +10 Hours [EMAIL PROTECTED] http://home.swiftdsl.com.au/~distudio//publications/ Pentax user since 1986, PDMLer since 1998 -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net
Re: Another k10D problem or just an old one?
Godfrey, As to your questions below: Light source was sunlight through the window. With the amount of snow on the ground, a lot of that light was reflected sunlight. I adjusted the white balance manually and it seemed fine. I am going to check it again with other light sources and some other subjects and without underexposure. No filters used or hood, but light was at my back so no light entering lens at oblique angles. Thanks for the reply. I sent a note to pentax USA, referring them to my images. Hope they take a look. Dave Godfrey DiGiorgi wrote: On Jan 30, 2007, at 4:00 PM, David Weiss wrote: So, is this just the infamous banding problem magnified a bit? No. Is this just my camera? I hope someone can verify for me that this is just a characteristic of this camera. Not that this would thrill me, because I expect something to work properly, but at least I wouldn't send my camera in again. I know that I am not likely to shoot under these conditions, but it would be nice if the camera worked properly just the same. No idea what's going on in these pictures. My K10D does not produce anything of the sort nor can I make it happen. What is the light source? You say it is natural light ... is it coming through a window? at an angle? Does it happen in any other lighting circumstances? Do you have UV or other filters on these lenses? Do you have lens hoods on them? G -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net
Re: Another k10D problem or just an old one?
- Original Message - From: David Weiss Subject: Re: Another k10D problem or just an old one? Paul Stenquist wrote: He's shooting jpegs on bright setting and underexposing by two to three stops. How can you conclude it's not normal? Wow, I thought people on this list could curb the sarcasm and help a person. Is that beyond everyone these days? I said this problem showed up on RAW photos as well. The problem is evident on picture number 3, which is clearly not underexposed. Dave, what part of reciprocity failure did you miss? I think it has to do with the low intensity of light playing havoc with the sensor. Try repeating the test at a wider aperture and see what happens. William Robb -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net
Re: Another k10D problem or just an old one?
Paul Stenquist wrote: I'm not being sarcastic. I didn't see the RAW images. If they were underexposed as badly as the jpegs, I wouldn't be surprised to see color appearing on white. I'm sorry if I wasn't helpful. You may have a problem. But as I said, it would be easier to tell with correct exposures and a normal range of tones. Your examples caused my scepticism. Sorry if I offended you. You may have a problem. Let's see some more examples. It's certainly not normal for the camera to produce color bands under standard or even somewhat extreme conditions. Can you shot a color scale card and a gray scale card in open shade? That could be revealing. You might also shoot something of a general neutral tone -- something close to medium gray or light brown-- in even light. Paul I'm sorry Paul, I was wrong in taking exception to what you said. I am sure if we were talking face to face, this would not have happened. I am a bit peeved with the whole situation as I just got the camera back and it seems I might have to send it back again. Never spent so much on one camera. Was just away for 3 weeks and was looking forward to using it. Of course, winter finally struck and that has slowed things down a bit. By the time I get home, it is getting dark during the week. I do understand your comments and will try to get some other examples. I was afraid that if I just showed you image 3 (the one that is about right in terms of exposure) that everyone would say I am imagining the problem or that my monitor is off or something like that. I could be wrong, but it looked to me that around f16 or so, the problem will be evident regardless. I will shoot a gray card, hopefully tomorrow, although I am going to an ENT specialist for a pinched nerve in my face. Well, that can put you on edge too! Maybe I will just shoot the graycard with the flash. Just not having a great week. Sorry again. Dave On Jan 30, 2007, at 9:32 PM, David Weiss wrote: Paul Stenquist wrote: He's shooting jpegs on bright setting and underexposing by two to three stops. How can you conclude it's not normal? Wow, I thought people on this list could curb the sarcasm and help a person. Is that beyond everyone these days? I said this problem showed up on RAW photos as well. The problem is evident on picture number 3, which is clearly not underexposed. This problem showed up on non-white subjects. What am I not saying correctly? I just wanted to know if it is a normal for this camera to do this under such conditions, that is all I wanted to know. I wasn't calling it a bad camera or anything else. Geez. Dave Paul On Jan 30, 2007, at 8:53 PM, Digital Image Studio wrote: On 31/01/07, David Weiss [EMAIL PROTECTED] wrote: So, is this just the infamous banding problem magnified a bit? No it's not banding but neither is it normal nor should it have to be tolerated. I would suggest that you pose the question to Pentax and send links to select images, ask them how to remedy the problem and if they can't solve it then have your camera swapped for a new one. -- Rob Studdert HURSTVILLE AUSTRALIA Tel +61-2-9554-4110 UTC(GMT) +10 Hours [EMAIL PROTECTED] http://home.swiftdsl.com.au/~distudio//publications/ Pentax user since 1986, PDMLer since 1998 -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net
Re: Another k10D problem or just an old one?
Hmm. I would be inclined to think that there's some odd refraction happening through the window which is not visible to the eye. I understand the captures are well-underexposed, that would exacerbate the appearance of the rainbow. Test with other lighting ... particularly one in which there is no glass in the light path. G On Jan 30, 2007, at 6:53 PM, David Weiss wrote: Godfrey, As to your questions below: Light source was sunlight through the window. With the amount of snow on the ground, a lot of that light was reflected sunlight. I adjusted the white balance manually and it seemed fine. I am going to check it again with other light sources and some other subjects and without underexposure. No filters used or hood, but light was at my back so no light entering lens at oblique angles. Thanks for the reply. I sent a note to pentax USA, referring them to my images. Hope they take a look. Dave -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net
Re: Another k10D problem or just an old one?
William Robb wrote: - Original Message - From: David Weiss Subject: Re: Another k10D problem or just an old one? Paul Stenquist wrote: He's shooting jpegs on bright setting and underexposing by two to three stops. How can you conclude it's not normal? Wow, I thought people on this list could curb the sarcasm and help a person. Is that beyond everyone these days? I said this problem showed up on RAW photos as well. The problem is evident on picture number 3, which is clearly not underexposed. Dave, what part of reciprocity failure did you miss? The part that says it applies to digital sensors. If it does, that is something I was totally in the dark about. If you have this documented somewhere, please send the link and I will read-up on it. I am very naive concerning such things. My image labeled 10 still shows the coloring affect, although not as strongly. It was shot at 1/10s, f13, 400 sensitivity. In your opinion, would that still qualify for reciprocity failure? Seems like it should be receiving adequate light, albeit underexposed about 1.5 to 2 stops. It seems to me that if I shot an image with these settings, and shadow of two stops was in the scene, I would still get this color problem in the shadow even if the rest of the scene was exposed correctly. I am not claiming this to be true, it just seems logical to me. If it is not, please explain why as I would truly like to understand this better. I am really just trying to understand this whole situation. I think it has to do with the low intensity of light playing havoc with the sensor. Try repeating the test at a wider aperture and see what happens. William Robb I will, hopefully in the next few days. Sorry for hassling the list. Dave -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net
Re: Another k10D problem or just an old one?
On 31/01/07, David Weiss [EMAIL PROTECTED] wrote: Light source was sunlight through the window. With the amount of snow on the ground, a lot of that light was reflected sunlight. I adjusted the white balance manually and it seemed fine. I am going to check it again with other light sources and some other subjects and without underexposure. Good move, this maybe the source of your problems, still very strange coloration though. -- Rob Studdert HURSTVILLE AUSTRALIA Tel +61-2-9554-4110 UTC(GMT) +10 Hours [EMAIL PROTECTED] http://home.swiftdsl.com.au/~distudio//publications/ Pentax user since 1986, PDMLer since 1998 -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net
Re: Another k10D problem or just an old one?
On 31/01/07, William Robb [EMAIL PROTECTED] wrote: You get reciprocity failure with film, why not with digital? Almost every time I see a problem with digital, it is the same type of scene. Someone takes an evenly lit white object, underexposes it 4 or so stops by stopping the lens way down, and then finds a problem. The technology ain't perfect, but at least you aren't whining about scratched negatives and lousy processing. Sorry Bill digicams don't exhibit reciprocity failure, just bad design and noise. -- Rob Studdert HURSTVILLE AUSTRALIA Tel +61-2-9554-4110 UTC(GMT) +10 Hours [EMAIL PROTECTED] http://home.swiftdsl.com.au/~distudio//publications/ Pentax user since 1986, PDMLer since 1998 -- PDML Pentax-Discuss Mail List PDML@pdml.net http://pdml.net/mailman/listinfo/pdml_pdml.net
