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  1. #11

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    I bet if you give us an image that is even smaller in size, it will look even more like a lens.

    I very surprised that you didn't seem to have any motion in the trees, maybe they just aren't resolved well enough to show it.

  2. #12

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    Can you tell us the name of the seller who sold you the pinholes on eBay? I for one wouldn't mind having a set of those pinholes!

  3. #13

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    Tree motion: Frankly, I cannnot remember if there was any wind, but I suspect not much. Regardless, when you look at the scan, the leaves are not really clearly resolved anyway.
    ~~~

    PINHOLES: Here is a link to one of his auctions, but you don't need to bid. You can contact him directly and get them for the same $29: http://cgi.ebay.com/PINHOLE-APERTURE...QQcmdZViewItem
    ~~~

    Mounting PS: For those interested, all I did to mount the pinhole was stick a piece of black gaffer tape over the rear of a lensboard drilled for a #1 shutter, black side of tape toward the inside, sticky side now showing through the front side of the lensboard hole. I cut an 8mm hole in the tape, centered in the lensboard hole, and then simply stuck the pinhole sheet to the front of the board over the tape, pinhole reasonably centered in the board's hole. The corners of the pinhole sheets needed to be clipped slightly to fit completely inside the #1 hole and I just used scissors to clip about 5mm off each corner. The gaffer tape is sticky enough to hold the pinhole, but not so sticky to prevent easy removal and swapping of pinhole sheets. The black tape with the small hole at the rear limits internal refections from the stainless steel
    ~~~

    Finally, I used this free program to make my aperture/focal length calculations -- I entered my own user constant of 1.6, generating slightly smaller suggested apertures than diffraction or Ralleigh: http://www.pinhole.cz/en/pinholedesigner/

    Cheers,
    Last edited by Jack_Flesher; 06-13-2007 at 10:47 AM. Click to view previous post history.

  4. #14
    Robert Hall's Avatar
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    Just pullin your leg, Jack. It's just that most of us have gone through the pin-hole stage (some have never left!) and probably dont do a lot of it because we just can't deal with the lack of clarity.

    Again, nice job.
    Robert Hall
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    Technology is not a panacea. It alone will not move your art forward. Only through developing your own aesthetic - free from the tools that create it - can you find new dimension to your work.

  5. #15

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    Hi Robert: No worries, I knew your meaning

    I should clarify that I was just having some fun with the pinhole and I don't really see it as a "serious" long-term endeavor on my part either. However I was slightly surprised that my "theory" of larger formats generating more pleasing results was more or less proven true! I also suspect there may be others who want to take pinhole more seriously, and just wanted to share my approach to set-up on the chance they find it helpful.

    Regardless, serious or not, carrying an extra lensboard and all 12 pinholes takes up zero room and adds only a few ounces of weight to the pack!

    Cheers,

    Jack

  6. #16
    htmlguru4242's Avatar
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    $29 for all of those pinholes is really not bad at all. If memory servers, I've seen single laser-drilled pinholes for close to that much. I wonder how pinhole would work out for infrared and UV images?

  7. #17
    PhotoBob's Avatar
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    Nice image

    Say that is a pretty nice pinhole image - thanks for sharing
    Follow the Light John 8:12
    ~~~PhotoBob

  8. #18
    Jim Jones's Avatar
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    Quote Originally Posted by htmlguru4242 View Post
    $29 for all of those pinholes is really not bad at all. If memory servers, I've seen single laser-drilled pinholes for close to that much. I wonder how pinhole would work out for infrared and UV images?
    They work well for IR and UV. A slight change in pinhole diameter optimizes sharpness for different wavelengths. http://www.pinhole.cz/en/pinholedesigner/ lets one adjust for this.

  9. #19

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    Thanks for the comment Bob!

    Jim, that is the same software I provided a link to above and it does indeed allow you to input the wavelength of light you are targeting to optimise. While I realize there is a theoretical optimum aperture I'm not convinced it is that critical for pinhole, at least on large format. If I am wrong in that assumption, please correct me! For 4x5 and 8x10, I simply go a little smaller than optimal, shooting for f256. (Makes it easy to do the exposure math!) Depending on what distance I place the pinhole, I figure as long as I'm between f180 and f360, it's probably good enough. HOWEVER, I suspect if one is using these on smaller formats, getting as close to optimal as possible is a good idea.

    Cheers,

    Jack

  10. #20
    Jim Jones's Avatar
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    Years ago I did some testing of on-axis and off-axis pinhole sharpness. There is a small, but noticable, peak in sharpness at the optimum aperture. This peak in on-axis sharpness occurs with a user constant of about 1.5 in
    Pinhole Designer. With this constant, a pinhole can resolve line pairs somewhat smaller than the pinhole diameter. A slightly larger pinhole favors off-axis sharpness with a reduction of on-axis sharpness. The old data on pinhole sharpness isn't handy at the moment, but I believe a pinhole diameter that varies from optimum by 10% causes a noticable loss of sharpness on a resolution chart. It would be less noticable in practical pinhole photography. There is a little more information on this in Matt Young's interesting paper at http://www.mines.edu/~mmyoung/PHCamera.pdf.

    Since the optimum pinhole diameter depends on light wave length, pinholes have slight chromatic aberration. The off-axis resolution between tangential and radial test pattern images are not equal. Thus, the pinhole has astigmatism. Testing for such characteristics is interesting, but the end of most photography should be photos, not tests. Some pinhole images are strong despite less than optimum sharpness.

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