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Finney pinhole body caps?

Auer

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I have a f200 0.13" Finney cap for a Pentax 645N, not sure if I like it or not...
What you guys think of these?


Canal House by Eric Auer, on Flickr

Pentax 645N | Finney Pinhole Cap 70mm ƒ200 0.13" Dia | Kodak Ektar 100 | CS Cd41 | CS F96 | Bleach Bypass
 
Nice photo considering the lighting and the camera used. However, detail that a pinhole camera can record increases with camera size and decreases with focal length. An 8x10" wide angle camera with a properly sized pinhole for 6" focal length will produce images that are obviously unsharp, but much sharper than this image. Sharpness is not always necessary in a photograph, but most subjects are not flattered with the amount of blur in an image from a small camera. A site with much information on pinhole cameras is https://jongrepstad.com/pinhole-photography/. If the pinhole bug really bites you, Eric Renner's book, Pinhole Photography: Rediscovering a Historic Technique, is a valuable resource.
 

Thanks, its allright for a first try.
I'll try some Ilford XP2 next.

Thanks for the links, I most likely will not go up in format size tho as I got too much on my plate already.
 
I've used a pinhole body cap on an M42 SLR on several occasions. At 43 mm projection distance (IIRC, that's flange to film for M42), with an optimal size pinhole it's possible to sort-of hand hold with film pushed to EI 1600 or higher.

If you have an existing plate camera, field camera, press camera, or other large format camera, you can unscrew the lens elements from the shutter, make up a pinhole that slips into the front of the shutter, collapse the bellows (most of the way) and get good results without spending a dime -- only an hour or so to make the pinhole insert -- and you'll already be set up to develop the film in that size. And if you don't, you can widen your 645 some if you look for a pinhole lens cap with a cone that juts into the body, and use it with mirror lock up. This will let you roughly halve your projection distance -- which, if you reduce the hole size enough to remain optimal, will significantly improve your overall sharpness.
 
Auer said:
Pentax 645N | Finney Pinhole Cap 70mm ƒ200 0.13" Dia | Kodak Ektar 100 | CS Cd41 | CS F96 | Bleach Bypass
Click to expand...

I have never used a Finney Pinhole Cap but I have used other pinhole body caps. Based on the other pinhole body caps I have used, I have not been satisfied with their image quality. In most cases, the pinhole size was off. I was able to make better images with pinholes made to my specifications.

The pinhole cameras I have made with a 70mm pinhole to image plane distance have had a pinhole diameter closer to 0.016 inch instead of the 0.13 inch of your pinhole body cap.

I think the Finney pinhole size may be too large.
 
The OP is likely mis-stating the body cap pinhole size. 0.13" is an eighth of an inch - that would be more like a lens aperture than a pinhole. It's probably 0.013" = 0.33mm. That would be f/200 at 66mm, which is about right for a body cap for a 645 camera.
 
Yeah, it's .013", a typo
 
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