Pinhole and filters
I am planning a backpacking trip into the high country in Montana this weekend. And I am considering bringing only my Zero Image 45 with me to push myself a little and step out of the comfort zone (plus it's way lighter then the Hasselblad). However, due to the bad fire year out here there is a lot of smoke and haze in the air. Does anyone use filters with their pinhole? I kind of feel like that defeats the purpose of "lensless" and might alter some of the feel of the inherent pinhole look. But it might be worth it to cut on the haze with either UV, CP or even yellow/orange and just tape it to the body or simply hold it. Also how do you compensate for the filter factor? I don't think UV would have any compensation but I just want to double check if the calcs are the same as with any other camera.
Anyway, any advice would be much appreciated. I plan on using one of the images from this trip as my contribution to the print exchange so one of you could really benefit from helping me out :D
I once used an 80B to finish off a roll of tungsten film in daylight, using a pinhole body cap -- it worked!
I have not used filters with B&W pinhole, but there has been discussion that reducing the spectrum width can produce a sharper image because the optimum pinhole diameter is light wavelength dependent. I would assume the same filter factors would apply. Because there is no light gathering or in/out of focus as with a lens, any specs of dirt on a filter are more likely to show in the photo than with a lens.
If going with paper negatives on graded paper, which is blue sensitive, a yellow filter can reduce burn-in of the sky.
I would lean toward a test or two before going. It's always nice to have a little confidence built before you're out in the field.
I have little cut up pieces of a kodak r29 gel behind all my pinholes. Only reason is to separate sky and clouds and get movement from long exposures.
I gave up on figuring exposure with reciprocity and filter factor. Seems like 1m 45s to 2m 15s works with about any 100 speed film.
I'd run some tests. I've found that my pinhole cameras do a lot of lovely things with clouds that you would need a yellow filter for if you were using a lens. I have no experience with the haze question, but never worried much about it either.
as for filter factors, less light is less light, the same amount less with or without a lens will mean the same compensation.
Originally Posted by aleksmiesak
I'm sure someone else will know better than I, but I'd think you might want the filter behind the pinhole if possible, since any smudges or dust or imperfections will be in the DOF of the pinhole!
I taped a piece of a gelatin filter behind the pinhole in my Zero Image 2-1/4 sq camera once to try to separate the sky & clouds... every scratch, dust speck, fingerprint etc showed up... didn't try it again.
As far as dust particulates in the sky... I am not sure that any type of filter will help eliminate that. Polarizers can help reduce fog and atmospheric haze, but not smoke or dust... I seem to remember reading that somewhere some time ago.
Hmmm... good comments so far. I think I'll try both ways and see what happens. I also have some old polaroid film that I might bring with me for test shots. I kind of feel the fire haze might not be as bad up that high anyway so I think I'll be fine. But I'll fire off a few polaroids just to be sure.
Thanks for all the good advice, I'll definitely let you all know how it went and maybe post a few shots on here when I get back.
Hope you all have a wonderful weekend!
I use filters on pinhole all the times and have never seen any dust or scratches. I put the filter in front of the pinhole. Some are proper screw in filters and some are cut up gel filters held in place with blu-tack. Same filter factors as when used with a lens of course.
If you're shooting sheet film, I'd be worrying more about reciprocity failure and calculating proper exposures. The type of film is important. Many people claim good results with Fuji Acros B/W, minimal reciprocity effect up to a minute or so (don't quote me on the exact time, it would pay to do your own homework). So you've got to have a system already in place regarding film and exposures.
For paper negatives, which I have some experience with, I'd recommend grade 2 RC paper rather than MG paper. Yes, some people claim good results (e.g. more moderate contrast) using a yellow filter with MG paper, but you'd have to do exposure tests, and also risk dust & scratches being visible from the filter, which are at least as bad as atmospheric haze. You also lose several stops of exposure with a yellow filter.
My current setup is to preflash (at home, in the darkroom) Freestyle's Arista-brand grade 2 RC paper, expose it at ISO12, and give it an extended development in dilute developer. Good contrast control, but of course with an actinic, 19th-century tonal range (e.g. blown out skies and dark skin tones). In cloudy daylight, exposure times with this paper can often be shorter than using traditional sheet film where you then have to extend your exposure times because of reciprocity failure. It especially helps to have it working at ISO12 and not having to apply a yellow filter, your exposure times remain moderately short.
Other advantages of paper over sheet film are less cost, less issues with dust (only one side shows dust vs two with film), scans easily on any flatbed scanner and quicker drying, especially RC paper negatives, a squeegee and hair dryer. Disadvantages of paper are slow ISO, less resolution if enlargement printing (yes, RC paper is translucent enough to projection enlarge) and slightly less sharpness if contact printing.
Paper negatives are ideal for a hybrid workflow of paper negative that's then scanned to digital for processing and printing or posting online, easier than any film.