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Thread: Post yer pinholes

  1. #311
    Len - www.lenbruffett.com
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    Re: Post yer pinholes

    A number of years ago a co worker gave me a cardboard camera kit that used a pinhole (brass) lens. I just found it in the garage and mounted the lens to an extra Linhoff lens board. I took a couple picks yesterday using ilford FP4 4x5 sheet film in my Linhoff MT. I took one 10 second exposure with the lens at the location on the rail bed where I use my 150mm lens and a second exposure where I locate my 90mm lens. The next time I am out making images I will take a couple of scenes of nature.

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  2. #312
    Tin Can's Avatar
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    Re: Post yer pinholes

    Quote Originally Posted by Greg View Post
    Years ago experimented with shooting through 25, 58, and 47B filters in order to get sharper pinhole images. Unfortunately my pinholes at the time were mediocre, so my results were less than valid. Also didn't like the non panchromatic image results.
    On this end I start with the pinhole's diameter as recommended in Eric Renner's book PINHOLE PHOTOGRAPHY. Made several pinholes at his recommended diameter in several different materials (Brass shim, Stainless Steel shim, DASANI sparking water aluminum can, aluminum foil, and a few more). Settled on Brass and Stainless Steel .002 gage shim stock. Both of the pinholes are blackened on the inside "walls" of the pinholes and then inspected under a microscope. If the pinhole isn't nearly perfectly round (most aren't), I re-blacken it and inspect again. Sometimes takes several tries. Compared the SS and the Brass pinholes and settled on using Brass shim stock because it was easier to blacken the surfaces. Then I make successively smaller pinholes to shoot test exposures with. Even though the pinholes will be used on an 8x10 (and another 11x14 to follow) WA camera, I shoot test exposures on 4x5 film at the same focal length of my 8x10 pinhole camera. Easier to batch process the 4x5s and way less expensive. I then compare the sharpness of the negatives and one almost always stands out. This is the one I use on my camera. When I determine which size hole to use, I make several more pinholes and then gently hammer the pinhole with a ball pean hammer to flatten the metal a bit more making the "wall" of the pinhole minimal thickness. I have to gently re-drill the pinhole after flattening it. Any burs around the pinholes are removed. Then blacken them. Having made several pinholes in this manner, I finally inspect them under my vintage Nikon Ske microscope with Axial (Brightfield) Illumination (hope I've used the correct terminology). They will all look different under the microscope so choose my favorite (and hopefully best). The pinhole images I get with my pinholes are noticeably sharper than any of the commercial "laser cut" pinholes I've purchased.

    Good to know
    Tin Can

  3. #313

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    Re: Post yer pinholes

    Anyone ever use a center neutral density filter on a pinhole?

  4. #314

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    Newbury, Vermont
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    Re: Post yer pinholes

    ND filter on a pinhole? Think of the reciprocity failure! Maybe one could leave such a setup alone for about a week? Someone should try this! (won't be me).

    But Greg...I'm intrigued by your very thoughtfully made pinholes. Would you think of offering them for sale?

  5. #315
    Len - www.lenbruffett.com
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    Re: Post yer pinholes

    Last week I went to ebay and found a laser drilled .5mm pinhole lens. It is mounted to a thin 2" diameter aluminum disk. I just mounted the disk to a metal lens board for my 4x5 field camera using simple silicon glue. As soon as the glue dries I will take a picture with the lens process it and post it. Here is the url to the seller on ebay. it was $12.99 + a $3. shipping fee

    https://www.ebay.com/itm/30324555509...53.m2749.l2649

  6. #316

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    Collinsville, CT USA
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    Re: Post yer pinholes

    Quote Originally Posted by John Layton View Post
    ND filter on a pinhole? Think of the reciprocity failure! Maybe one could leave such a setup alone for about a week? Someone should try this! (won't be me).

    But Greg...I'm intrigued by your very thoughtfully made pinholes. Would you think of offering them for sale?
    Gave it a little bit of thought once, but then decided against it. First off people seem to prefer "laser cut" pinholes. I purchased some "Laser Cut" pinholes from different dealers/makers at one time. 6 total. 2 of them were of excellent quality and precision.The other 4 ranged from a wee bit oval to one being absolutely the wrong (described) size and with ragged edges. When viewed under a microscope I would have to say that only one may have been made using a Laser. The other 5 I'd bet were not, and I'm not a betting person. Got me to wonder just how "precision" pinholes were made by a Laser. To me it seems like the Laser would be cost prohibitive to be purchased to (just) make Laser cut pinholes that one could market for maybe only $10.00 each.

    Can anyone out there describe just what type of Laser would be used for making "precision" Laser pinholes?
    Cost of the Laser?

  7. #317

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    Summerville, SC
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    1,816

    Re: Post yer pinholes

    Quote Originally Posted by Greg View Post
    Gave it a little bit of thought once, but then decided against it. First off people seem to prefer "laser cut" pinholes. I purchased some "Laser Cut" pinholes from different dealers/makers at one time. 6 total. 2 of them were of excellent quality and precision.The other 4 ranged from a wee bit oval to one being absolutely the wrong (described) size and with ragged edges. When viewed under a microscope I would have to say that only one may have been made using a Laser. The other 5 I'd bet were not, and I'm not a betting person. Got me to wonder just how "precision" pinholes were made by a Laser. To me it seems like the Laser would be cost prohibitive to be purchased to (just) make Laser cut pinholes that one could market for maybe only $10.00 each.

    Can anyone out there describe just what type of Laser would be used for making "precision" Laser pinholes?
    Cost of the Laser?
    I've used these with great success.

    https://www.2spi.com/category/grids-...ture/grids-cu/

  8. #318
    Tin Can's Avatar
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    Dec 2011
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    Re: Post yer pinholes

    Sometimes I wish I still had access to the Hole Factory

    Non-Traditional Methods For Making Small Holes


    Quote Originally Posted by jon.oman View Post
    I've used these with great success.

    https://www.2spi.com/category/grids-...ture/grids-cu/
    Tin Can

  9. #319

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    Re: Post yer pinholes

    I have a couple from https://daystarlaser.com/ that do a nice job. Not especially cheap (particularly the Copal #0 mount) but they are cleaner than my hand made ones.

  10. #320
    Tin Can's Avatar
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    Re: Post yer pinholes

    BINGO!

    I will order soon

    I forgot Dirk

    Thank you




    Quote Originally Posted by Graham Patterson View Post
    I have a couple from
    https://daystarlaser.com/ that do a nice job. Not especially cheap (particularly the Copal #0 mount) but they are cleaner than my hand made ones.
    Tin Can

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