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  1. #31

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    Thomas, all my pinholes have red 25's permanently mounted. I initially put them there because I like sky images and cloud motion, and the reds really darken the sky and add a couple stops exposure. But the only time the hole is exposed is when loading or unloading film in the darkroom, so I have seen no need to clean them.

    The reds appeared to improve "sharpness" compared to unfiltered, by restricting other wavelenghts (so I am told). What really helped was smoking the holes over an oil lamp, then recapitulating them with the needle and checking under the scope. Where there were microscopic metal shards, they were filled in with the soot and the holes now appear laser drilled. What this did to the effective thickness of the hole, I don't know. But it appears to have helped.

    I have a dozen negs I'm working on now, and hope to get some stuff up soon. 'Tis the season to p-hole!

  2. #32

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    As far as the material for my pinhole I have chosen aluminum. The pinhole is to be created with an engraving laser that I use at work
    Bachelor of Fine Arts and Bachelor of Arts: Journalism - University of Arkansas 2014

    Canon A-1, Canon AE-1, Canon Canonet GIII 17, Argus 21, Rolleicord Va, Mamiya RB67, Voigtländer Bessa

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  3. #33
    Thomas Bertilsson's Avatar
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    Rich,

    With pinhole having pretty much infinite depth of field, I have always been wary of using filters with them. But I might purchase some gel filters and give it a go. I'd probably use an orange filter, though.

    Thanks for the tip.

    - Thomas

    Quote Originally Posted by Rich Ullsmith View Post
    Thomas, all my pinholes have red 25's permanently mounted. I initially put them there because I like sky images and cloud motion, and the reds really darken the sky and add a couple stops exposure. But the only time the hole is exposed is when loading or unloading film in the darkroom, so I have seen no need to clean them.

    The reds appeared to improve "sharpness" compared to unfiltered, by restricting other wavelenghts (so I am told). What really helped was smoking the holes over an oil lamp, then recapitulating them with the needle and checking under the scope. Where there were microscopic metal shards, they were filled in with the soot and the holes now appear laser drilled. What this did to the effective thickness of the hole, I don't know. But it appears to have helped.

    I have a dozen negs I'm working on now, and hope to get some stuff up soon. 'Tis the season to p-hole!
    "Often moments come looking for us". - Robert Frank

    "Make good art!" - Neil Gaiman

    "...the heart and mind are the true lens of the camera". - Yousuf Karsh

  4. #34

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    Darkroom, the best material I have found for the holes is stainless steel dental matrix bands. Any dental office would be glad to hand over a couple, they are dirt cheap. The "dead soft" bands I believe are .0015" thick, which is hard to beat. They sand beautifully, and you can probably make four holes out of one band.

    Maybe with your engraving laser it's not necessary or helpful to smoke them.

  5. #35
    bowzart's Avatar
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    My material of choice is pure silver, rolled to .003. I make the hole too big, and with a polished hammer and anvil, I thin and expand the metal with the hole in it. This will make the hole too small, so I repeat this routine over and over, bringing the hole gradually to correct size. There are episodes of dressing, as needed, with a fine jeweler's file. This results in a domed, work hardened square of silver of unknown, but extremely small thickness. I wouldn't blacken with smoke, because of the change in dimension as well as it's susceptibility to rubbing off. Instead, I simply selenium tone the silver, which doesn't affect the dimension. Although it isn't "perfectly" black, the silver, over time, will continue to darken. You know, tarnish.

    I am very leery of laser drilled holes, because they will inevitably be tubes. This would be ok, if the material is thin enough. I believe the best holes to be hand finished, and as close to knife edged as possible. It is handy to have had some jewelry experience and facility in working with metal.

    About the filter thing, I more or less gave up on it. Eric Renner had suggested I research it and contribute my findings to I guess it must have been the second edition of his book. When I put the filter on - this was gels - every little thing that could get on the filter produced an ugly spot in the negative. With 8x10 film, that was pretty expensive. Of course, doing this out on the desert didn't help. I got to thinking that the solution to the problem would be to fill the pinhole with gel, so that any garbage would be both less likely to be there and couldn't produce the kind of problem I was getting.

  6. #36
    bowzart's Avatar
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    Quote Originally Posted by Thomas Bertilsson View Post
    Rich,

    With pinhole having pretty much infinite depth of field, I have always been wary of using filters with them. But I might purchase some gel filters and give it a go. I'd probably use an orange filter, though.

    Thanks for the tip.

    - Thomas
    One thing working for us with filters is that when anything is closer to the hole (in front) than the FL, it is enlarged and progressively less sharp. If it could be close enough to the hole, the image of it would enlarge to the point where it would be so nebulous that it would have very little if any visible effect on the image.

  7. #37

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    I've ran into some sharpness issues. I took the ground glass from RB67 and checked my pinhole camera, nothing appears to be even close to sharp. Is this a good indicator? Do I need to make the pinhole smaller, it is currently .4mm.
    Bachelor of Fine Arts and Bachelor of Arts: Journalism - University of Arkansas 2014

    Canon A-1, Canon AE-1, Canon Canonet GIII 17, Argus 21, Rolleicord Va, Mamiya RB67, Voigtländer Bessa

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  8. #38
    Poisson Du Jour's Avatar
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    A glass filter (gel filters are lousy for any photography) can be successfully employed with no adverse effect on the image by mounting it behind the pinhole, edges masked. It's when you put a filter in front of a pinhole that image quality dramatically suffers.


  9. #39
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    It would be helpful to know your pinhole to focus plane distance, and also, if you can, to see an image of you pinhole made at about fifty to 100 x or so. Smaller is not generally the answer.

    Maybe you are thinking that a pinhole image should compete with a lens on the lens' terms. It can't, and ought not be expected to. If it did, why bother? The parameters are different. Lenses and pinholes are NOT the same thing, and what they do is different. You can have a sharp image from a pinhole, but it doesn't look like a sharp image made with a lens.

    I have a pinhole that I use in my Leicas, but I use it when I don't want to do what Leitz likes to see! I sent one to Germany with a friend who was visiting Leitz, and was very unhappy when he told me he was too "chicken" to show it to them. Bummer. I suspect someone would have been interested. He said they seemed to like beer a lot. But he kept the body cap with the pinhole mounted in it in his pocket!

    You might not like what the pinhole gives you. Or, you might not like it NOW, but be sure to look again in a few years. We change, too. I'd never have accepted the kind of image a pinhole makes had I started making them prior to ten years into my career. Really. But now I love it, IF it meets my rather stringent standards.

  10. #40
    bowzart's Avatar
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    Quote Originally Posted by Poisson Du Jour View Post
    A glass filter (gel filters are lousy for any photography) can be successfully employed with no adverse effect on the image by mounting it behind the pinhole, edges masked. It's when you put a filter in front of a pinhole that image quality dramatically suffers.
    It will affect the image either way, it depends on how close to the hole it is located. Yes, it would probably be different, but not that much. Glass filters would be just as bad or worse, because they have greater thickness. It's not imperfections in the surface here, that are the problem. It's what is on the surface and how far it is from the hole.

    I have used gel filters for many, many years and they work just fine if you are careful to use them as they must be used. Best, of course, is to unscrew one of the elements of a lens and put a filter cut in a circle to size inside, then screw it back in. I have several lenses that have permanent gels installed. I have used my 8x10 Master View as an "ensmaller" to reduce an 11x14 negative, much in demand, itself made with a set of gel filters. It was an image of a theater interior. I shot color paper in the 8x10 for the client to gift it's board members when they retired. So, there were several trips through gels, both in shooting and in printing with no visible effects at all. Now, I've been doing this for 45 years professionally. If there were a problem, I'd have seen it.

    Perhaps you had a bad experience? How can you be sure that the gels were the problem?

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