Re: [pinhole-discussion] re: calculating exposure
The Black Cat Exposure Calculator sold at Pinhole Resource is a dial calculator that extends to very small aperatures ( f/ 1024) and long exposure times (27 hours). It doesn't include reciprocity, since that varies from one film type to the next. Mike Vande Bunt Richard Koolish wrote: It's easy to make a dial calculator like the one on an exposure meter, but that goes to longer exposures and slower film speeds. I've got one on my web page at http://linux.bbn.com/~koolish ___ Pinhole-Discussion mailing list Pinhole-Discussion@p at ??? unsubscribe or change your account at http://www.p at ???/discussion/
Re: [pinhole-discussion] re: calculating exposure
Thanks for the dial calculator. I downloaded it and am going to make one. I have been using something similar but it is a bit more cumbersome. I made a long slide-rule with all of the f-stops and speeds projected beyond my handheld light meter. The only information my slide rule has that the dial doesn't have is that I have included f-stops and shutter speeds halfway between each of the standard settings. For example: the extra f-stop between f/22 and f/32 would be f/27.25. I have done this all the way up to f/4096 and 16,384 seconds (or 4.5 hours). Most people don't need to go that high but you never know. I just copied the dial on my LunaPro meter and extended it. First I made a pencil copy, then figured out how to do it in postscript. Certainly beats trying to do it in your head. Your slide rule idea works too. It's just the dial straightened out. I tried it straight before trying the dial.
Re: [pinhole-discussion] re: calculating exposure
It's easy to make a dial calculator like the one on an exposure meter, but that goes to longer exposures and slower film speeds. I've got one on my web page at http://linux.bbn.com/~koolish Thanks for the dial calculator. I downloaded it and am going to make one. I have been using something similar but it is a bit more cumbersome. I made a long slide-rule with all of the f-stops and speeds projected beyond my handheld light meter. The only information my slide rule has that the dial doesn't have is that I have included f-stops and shutter speeds halfway between each of the standard settings. For example: the extra f-stop between f/22 and f/32 would be f/27.25. I have done this all the way up to f/4096 and 16,384 seconds (or 4.5 hours). Most people don't need to go that high but you never know. Andrew ___ Send a cool gift with your E-Card http://www.bluemountain.com/giftcenter/
[pinhole-discussion] re: calculating exposure
It's easy to make a dial calculator like the one on an exposure meter, but that goes to longer exposures and slower film speeds. I've got one on my web page at http://linux.bbn.com/~koolish
Re: [pinhole-discussion] calculating exposure when you know the pinhole diameter.
Or you can use my calculator and print out a chart of the exposures at http://www.MrPinhole.com/Exposure.html Larry -Original Message- From: William Erickson erick...@ic.mankato.mn.us To: pinhole Discussion pinhole-discussion@p at ??? List-Post: pinhole-discussion@pinhole.com Date: Thursday, December 28, 2000 2:14 PM Subject: [pinhole-discussion] calculating exposure when you know the pinhole diameter. I just read the article G. Penate referred to about calculating exposures, by calulating the f stop of the pinhole and trying to devine the exposure by
Re: [pinhole-discussion] calculating exposure when you know the pinhole diameter.
I just read the article G. Penate referred to about calculating exposures, by calulating the f stop of the pinhole and trying to devine the exposure by counting f stops from a referral point. It doesn't need to be that hard. 1. Measure the pinhole to film distance and divide by 22. That gives you the diameter of f22 for that distance. 2 Then calculate the area of this f22 aperture by multiplying half the diameter x half the diameter x 3.14. 3.Then measure the diameter of the pinhole, using the same measure as you did before, inches or millimeters both times. 4.Then calculate the area of the pinhole using the same formula. 5. Then divide the area of the pinhole into the area of the F22 aperture you calulated, and use the result to multiply times the metered exposure at f22. At an optimal pinhole to film distance of three inches, for instance, the multiplier is about 120. If the metered exposure at f22 is 1/10 second, the calculated metered exposure for the pinhole would be 12 seconds. You can drive yourself batty trying to work it through the f stop comparison method. The beauty of math is you can get to Rome using many roads. The example I give is using sunny-16, so I ask you to find the number of stops separating f/16 to the f/stop of your pinhole, in the case of the example is 9. Then I ask you to double the exposure time 9 times, which is the same as finding 2 to the power of 9 or 2^9 = 512 that 512 is the MULTIPLIER, again in the example the exposure using sunny-16 is f/16 and 1/6secs then the exposure for the pinhole would be 1/6 * 512 or 512 / 6 = 85 which is the same thing as doubling 1/6 9 times. The idea of doublings is that you are just adding, sometimes I am afraid of suggesting anything that has powers or roots because I want the explanation to be as down to basics as possible. Nevertheless, anybody that has at least high school should know that doubling the number two n number of times is equal to 2^n. Guillermo
Re: [pinhole-discussion] Recommended Exposures onto Paper
Guillermo, The picture mentioned in your article looks like one of the Big Banks' doors in Toronto. Is that the case? It belongs to the a Greek Ortodox church in the Don Mills area. Hmmm... 19 degrees below freezing (Celsius or Farenheight?) sounds just about like the kind of weather you would get on a really bad day in Toronto Celsius, but still freezing cold. Why would anyone want to do 55 minutes exposures in that kind of weather? I was in my honey moon with pinholing, back then!! Don't tell me you didn't do one or two crazy thing when you were in love with something or someone. :-) I hope that your body was well covered! -:)) Had car parked and running near by so from time to time I went inside to warm up a bit. Love wasn't that deep after all!!. in Montréal, where the temperature is currently 10 Celsius below freezing (about minus 30 Fareinheight) and not too happy to have to go out shopping with his lovely wife when I could be staying relaxing in the warmth of my home...! -:)) I don't care if it is -10 or +25 celsius, I just don't go shopping, I just don't go to malls. BTW, -10 celsius are +14 Farenheight. Guillermo Guillermo
Re: [pinhole-discussion] pinhole 411
thanks!!! :) -jm
[pinhole-discussion] calculating exposure when you know the pinhole diameter.
I just read the article G. Penate referred to about calculating exposures, by calulating the f stop of the pinhole and trying to devine the exposure by counting f stops from a referral point. It doesn't need to be that hard. 1. Measure the pinhole to film distance and divide by 22. That gives you the diameter of f22 for that distance. 2 Then calculate the area of this f22 aperture by multiplying half the diameter x half the diameter x 3.14. 3.Then measure the diameter of the pinhole, using the same measure as you did before, inches or millimeters both times. 4.Then calculate the area of the pinhole using the same formula. 5. Then divide the area of the pinhole into the area of the F22 aperture you calulated, and use the result to multiply times the metered exposure at f22. At an optimal pinhole to film distance of three inches, for instance, the multiplier is about 120. If the metered exposure at f22 is 1/10 second, the calculated metered exposure for the pinhole would be 12 seconds. You can drive yourself batty trying to work it through the f stop comparison method.
Re: [pinhole-discussion] Zone Plate Image Generator
Ok, I just cleaned it up a bit and compiled it. You can download it from my local machine at ftp://pinhole:pinh...@cosmic9.dyn.dhs.org:21. Zone.exe is the program itself, and zone prog source.zip is the source code. I'm 56k so it might go pretty slow, but they're small files so it doesn't matter. George expressed interest in posting my program on his website, http://members.home.net/hmpi/, so you can probably get it there also. I'm taking a more advanced visual basic class next semester, so i might improve on it. You will probably need the visual basic run time file to run it, you can get that at ftp://ftp.simtel.net/pub/simtelnet/win95/dll/simvb6-6.zip. John - Original Message - From: Larry Fratkin To: pinhole-discussion@p at ??? Sent: Thursday, December 28, 2006 6:28 AM Subject: Re: [pinhole-discussion] Zone Plate Image Generator John and folks, If people would like one for photographing I would be happy to do it. Just let me know if there's interest. The calculators on my site were usually made because I thought I needed them and then thought that maybe others need them too. I would be interested in seeing the source code to see how you did it. I'm also curious what format you generated. My web host only allows Perl, so I'd have to translate it. Larry -Original Message- From: John Yeo jonn...@thegrid.net To: pinhole-discussion@p at ??? pinhole-discussion@p at ??? Date: Wednesday, December 27, 2000 9:54 PM Subject: Re: [pinhole-discussion] Zone Plate Image Generator Hi Larry, Nevermind that. For some reason, microsoft paint displayed nothing, while photoshop displayed it properly. I was expecting an output that one would photograph from a distance like what they have at http://members.home.net/hmpi/Pinhole/Articles/ZonePlate/Zone_Plate.htm. Is that how it is supposed to work, or does it give one the actual size? I made a zone plate calculator a while ago in visual basic. It calculated ring sizes, magnified sizes (for photographing from a distance) and also calculated the true f stop (just the area of the clear rings). If anyone wants it, I can compile it and send it out. If you want to add to it, let me know and i'll give you the source code. I don't really care what you do with it, post it on the web, whatever. John - Original Message - From: Larry Fratkin To: pinhole-discussion@p at ??? Sent: Wednesday, December 27, 2006 6:47 PM Subject: Re: [pinhole-discussion] Zone Plate Image Generator john, Yes, I did put a few hours into this, but it was fun. Thanks for appreciating that. What were the settings you typed in? I'd like to repeat them to see what I get. Also, sometimes you really have to look for the zone plate in the middle of the image. Larry -Original Message- From: John Yeo jonn...@thegrid.net To: pinhole-discussion@p at ??? pinhole-discussion@p at ??? Date: Wednesday, December 27, 2000 4:48 PM Subject: Re: [pinhole-discussion] Zone Plate Image Generator Larry, Thanks for making this. I'm sure you have already put a lot of work into it... but i get nothing but a blank bitmap. No rings at all. John - Original Message - From: Larry Fratkin To: pinhole list Sent: Wednesday, December 27, 2006 3:52 PM Subject: [pinhole-discussion] Zone Plate Image Generator Folks, I have created a zone plate image generator so that I could make my own zone plates. The program downloads a .BMP so it's PC centric, I think. The idea was to use the program to generate a zone plate image and then take it to the bureau to have it put to film. They charge about $15.00 for this. I haven't tried it out yet so I don't know how well it works. I'll be visiting them on Friday and I'll drop it off then. The calculator/generator is at http://www.MrPinhole.com/zp.html la...@mrpinhole.com
Re: [pinhole-discussion] Recommended Exposures onto Paper
G.Penate wrote: They appear in the small article I wrote and that you can see at: http://members.home.net/penate/pinsize.htm G.Penate wrote in the above mentioned article: When I was making DOOR A big cloud passed by during part of the 40 minutes, that made me extend the exposure time to 55 minutes to compensate. During this time, I also exposed my body for 55 minutes to 19 degrees bellow the freezing mark!! Guillermo, The picture mentioned in your article looks like one of the Big Banks' doors in Toronto. Is that the case? Hmmm... 19 degrees below freezing (Celsius or Farenheight?) sounds just about like the kind of weather you would get on a really bad day in Toronto or similar. Why would anyone want to do 55 minutes exposures in that kind of weather? I hope that your body was well covered! -:)) Best, Guy Glorieux in Montréal, where the temperature is currently 10 Celsius below freezing (about minus 30 Fareinheight) and not too happy to have to go out shopping with his lovely wife when I could be staying relaxing in the warmth of my home...! -:))
[pinhole-discussion] pinhole 411
Hi there!!! Looking for help/ directions on how to build myself a pinhole camera out of a square 'Tide'/like detergent box that I'd like to fit with a 600 series Polaroid film carrier backI have never made a pinhole camera before so have no knowledge of even where to begin (or what I now do with the Polaroid film carrier things that I bought off eBay!) Just know that I've heard I can combine these ingredients to make beautiful photographs I'm hoping you all might be familiar with this, or could lead me to information that could guide me... Again, I'm a complete novice here, so sure hope I'm not asking too much! Thanks very much for the help ... -Jennifer
Re: [pinhole-discussion] Recommended Exposures onto Paper
- Original Message - From: Larry Fratkin la...@mrpinhole.com To: pinhole-discussion@p at ??? Sent: Thursday, December 28, 2006 9:32 AM Subject: Re: [pinhole-discussion] Recommended Exposures onto Paper I'm also interested in knowing about paper's reciprocity. Is it anything like film? I know it's made for longer exposures but I think that just means the curve is a little further out in time. Does anyone have information on this? Larry, There is a book(let) call something like Minimal aperture photography, from it I took the reciprocity correction I have used with some success. They appear in the small article I wrote and that you can see at: http://members.home.net/penate/pinsize.htm Guillermo
Re: [pinhole-discussion] Zone Plate Image Generator
Guy, Yup, it makes perfect sense. You're right, mounting usually involves cutting away most of the film. I'll look into generating multiple zone plates per image. It should be relatively simple. Then, if Eric wants to make zone plates to sell, he can do it economically by having many images in one frame. I also thought about contact printing the image after I get the first one back. Larry -Original Message- From: Guy Glorieux guy.glori...@sympatico.ca To: pinhole-discussion@p at ??? pinhole-discussion@p at ??? Date: Thursday, December 28, 2000 9:08 AM Subject: Re: [pinhole-discussion] Zone Plate Image Generator Larry, Many thanks for this great little tool! I needed a 30mm zone plate for one of my short focal cameras but the last I knew from Eric Renner when I was looking for that short focal length is that he did'nt have any. It occured to me that this is very tiny little spot on a 35mm film size (24x26mm), with a lot of wasted film around it that has to be cut out anyway to fit on the hole of the camera. So what I want to do is to place several zone plates on the same 24x36mm space. I could do this by generating several zone plate files and then cutting and pasting them with Photoshop on one single sheet of film. Or, if you have friends who want zone plates as well, you could share the cost of the lab by placing perhaps 4 zone plates on the same sheet of film. Seems to make sense. Does it? Larry Fratkin wrote: Folks, I have created a zone plate image generator so that I could make my own zone plates. The program downloads a .BMP so it's PC centric, I think. The idea was to use the program to generate a zone plate image and then take it to the bureau to have it put to film. They charge about $15.00 for this. I haven't tried it out yet so I don't know how well it works. I'll be visiting them on Friday and I'll drop it off then. The calculator/generator is at http://www.MrPinhole.com/zp.html la...@mrpinhole.com
Re: [pinhole-discussion] Zone Plate Image Generator
Larry, Many thanks for this great little tool! I needed a 30mm zone plate for one of my short focal cameras but the last I knew from Eric Renner when I was looking for that short focal length is that he did'nt have any. It occured to me that this is very tiny little spot on a 35mm film size (24x26mm), with a lot of wasted film around it that has to be cut out anyway to fit on the hole of the camera. So what I want to do is to place several zone plates on the same 24x36mm space. I could do this by generating several zone plate files and then cutting and pasting them with Photoshop on one single sheet of film. Or, if you have friends who want zone plates as well, you could share the cost of the lab by placing perhaps 4 zone plates on the same sheet of film. Seems to make sense. Does it? Larry Fratkin wrote: Folks, I have created a zone plate image generator so that I could make my own zone plates. The program downloads a .BMP so it's PC centric, I think. The idea was to use the program to generate a zone plate image and then take it to the bureau to have it put to film. They charge about $15.00 for this. I haven't tried it out yet so I don't know how well it works. I'll be visiting them on Friday and I'll drop it off then. The calculator/generator is at http://www.MrPinhole.com/zp.html la...@mrpinhole.com
[pinhole-discussion] FW: PlanetEE Portal
could be an interesting base for a 3-d Pinhole camera... andy -Original Message- From: Ken Wurtzel Sent: Wednesday, December 20, 2000 11:37 AM To: David C Wurtzel (E-mail); Andy Schmitt (E-mail) Subject: PlanetEE Portal Go to the latest issue, Designers Turn LCD Technology Into A Single-Lens, Stereo Image Shutter story... http://www.elecdesign.com/
RE: [pinhole-discussion] print swap publication
Sounds like an interesting concept... andy -Original Message- From: pinhole-discussion-admin@p at ??? [mailto:pinhole-discussion-admin@p at ???]On Behalf Of Kosinski Family Sent: Tuesday, December 26, 2000 8:11 AM To: Pinhole Discussion List Subject: [pinhole-discussion] print swap publication I think it would be easy to organize the whole thing from one place. Everyone sends their print to a coordinator, who arranges for it to be reproduced and distributed. A small book (or portfolio) would be great as books are not that expensive to mail from the USA. I'm for an open theme, with a journal type entry about the picture, contact info, and a self portrait for each participant (if you wish). Will look into reproduction costs right after the New Year Holiday, as there is a very good bw printer in the region with decent pricing. The only inexpensive digital prints that last are those made on laser printers, others fade miserably in less than a year. Will also start looking for sponsors grants and encourage everyone else to do the same. I guess I'm volunteering to coordinate if there is a consensus. Best wishes for the New Year! Jim Kosinski Starlight Cameras PO Box 540 Cherry Valley NY 13320 USA
Re: [pinhole-discussion] PRINT SWAP: Pinhole Puzzle
Guy, Wont' you miss the rain and cold winters of Germany? Well observed, Guy. With the summer and fall busy, I can spend my vavation during the off-season back in the cold [grin];-). Erich P.S. Among other things, I hope to promote 'Fotografia Sin Lente' while I'm there.
Re: [pinhole-discussion] PRINT SWAP: Pinhole Puzzle
Erich wrote: Otherwise you have to come to the Balearic island of Ibiza, where I will live next year. Erich, Oh, this will be a difficult life... Cloistered on an paradisiac island... With all that sun and blue sea around... -:)) My daughter was there in the September. She said it's like a Black Hole: you get drawn into it and when you're inside, you can never can get outside... Wont' you miss the rain and cold winters of Germany? Guy Glorieux
Re: [pinhole-discussion] Recommended Exposures onto Paper
Hi, Someone once told me that the ISO P, the one we find with the paper instructions, is 1/100 of the film ISO. So, using the Ilford paper as an example, w/o. filter the paper is ISO P 500 giving us aprox. ISO 5 for film meters. Using filters for multicontrast, the ISO P might be 200 or 100 thus giving us a meter setting of ISO 2 or 1. If it is true, well I haven't tested yet, but if someone did, I'd love to hear. Joao I would use iso 6 for most papers.I would also recomend rc for the negative.
Re: [pinhole-discussion] PRINT SWAP: Pinhole Puzzle
Hmmm, next time i'm visiting friends in Portland, Or. we could get together for a chat ;-) I'm in Washington... located in Snohomish, 25 miles NE of Seattle. Otherwise you have to come to the Balearic island of Ibiza, where I will live next year. Erich (still Germany)
Re: [pinhole-discussion] PRINT SWAP: Pinhole Puzzle
Leezy, I'm in Washington... located in Snohomish, 25 miles NE of Seattle. Levi
Re: [pinhole-discussion] Zone Plate Image Generator
Hi Larry, Nevermind that. For some reason, microsoft paint displayed nothing, while photoshop displayed it properly. I was expecting an output that one would photograph from a distance like what they have at http://members.home.net/hmpi/Pinhole/Articles/ZonePlate/Zone_Plate.htm. Is that how it is supposed to work, or does it give one the actual size? I made a zone plate calculator a while ago in visual basic. It calculated ring sizes, magnified sizes (for photographing from a distance) and also calculated the true f stop (just the area of the clear rings). If anyone wants it, I can compile it and send it out. If you want to add to it, let me know and i'll give you the source code. I don't really care what you do with it, post it on the web, whatever. John - Original Message - From: Larry Fratkin To: pinhole-discussion@p at ??? Sent: Wednesday, December 27, 2006 6:47 PM Subject: Re: [pinhole-discussion] Zone Plate Image Generator john, Yes, I did put a few hours into this, but it was fun. Thanks for appreciating that. What were the settings you typed in? I'd like to repeat them to see what I get. Also, sometimes you really have to look for the zone plate in the middle of the image. Larry -Original Message- From: John Yeo jonn...@thegrid.net To: pinhole-discussion@p at ??? pinhole-discussion@p at ??? Date: Wednesday, December 27, 2000 4:48 PM Subject: Re: [pinhole-discussion] Zone Plate Image Generator Larry, Thanks for making this. I'm sure you have already put a lot of work into it... but i get nothing but a blank bitmap. No rings at all. John - Original Message - From: Larry Fratkin To: pinhole list Sent: Wednesday, December 27, 2006 3:52 PM Subject: [pinhole-discussion] Zone Plate Image Generator Folks, I have created a zone plate image generator so that I could make my own zone plates. The program downloads a .BMP so it's PC centric, I think. The idea was to use the program to generate a zone plate image and then take it to the bureau to have it put to film. They charge about $15.00 for this. I haven't tried it out yet so I don't know how well it works. I'll be visiting them on Friday and I'll drop it off then. The calculator/generator is at http://www.MrPinhole.com/zp.html la...@mrpinhole.com
