8x10 inch pinhole test

Discussion in 'Pinhole Photography' started by jon.oman, Dec 9, 2011.

  1. jon.oman

    jon.oman Member

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    Well, I finally have a darkroom that can handle 8x10 inch film. So, I needed to test the 8x10 inch pinhole camera that I made a year or so ago. You may remember this image:

    [​IMG]

    I learned a few things in getting here. The biggest thing is that things always take longer than you think they will. Life keeps getting in the way!

    So, here is one of two test shots I took today:

    [​IMG]

    This is a slight crop to remove most of the vignetting. It turns out that the hole my pinhole is mounted in is too small. I will have to drill it out to a bigger size. If I don't, the corners will be cut off.

    I also had to determine the correct exposure for the f300, 120mm camera that I made. I used the Mr. Pinhole site to come up with a starting point, so that I could use my exposure meter:

    http://www.mrpinhole.com/lightmeter.php

    With this program, I determined that I could set my meter at 4 ISO, and use the time given on the meter for f45 as the exposure time. For the above pinhole image, the meter gave me one minute as the time. With this time, I needed to worry about reciprocity. So, I used the information I found here as a guidline:

    http://www.apug.org/forums/forum37/76797-x-ray-film-reciprocity-effect.html

    That's correct, I am using green laditude x-ray film. At thirty cents a sheet for 8x10, I can aford it!

    So, I used an exposure of ten minutes for the first pinhole image above. That was to allow for reciprocity.

    Since I wanted to see what the image would look like at the one minute indicated time, I made this image:

    [​IMG]

    I had an easier time scanning in this negative, but it does lack a lot of highlight detail. So, even though the ten minute image above was not easy to scan, I like the end result better.

    By the way, I developed both negatives in undiluted D-76 for six minutes.

    Now, can you see the 'ghost' in the first image?
     
  2. Rich Ullsmith

    Rich Ullsmith Subscriber

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    The idea for xray film for pinhole is fantastic! You should be able to develop by inspection, with the right safelight. And 30 cents a sheet is unbeatable. Fill the freezer!
     
  3. jon.oman

    jon.oman Member

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    I'm thinking about filling the freezer with this film!
     
  4. ced

    ced Member

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    jon.oman fantastic and amazing what one can do without a lens! Very nice looking camera too!
    Here is my take hope you are not offended. House_10min_test_cropped.jpg
     
  5. jon.oman

    jon.oman Member

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    I'm glad that you like what I've done here. Remember, it is a test, so I did not worry too much about cropping. I have no problems with what you did!

    I have fixed the hole size that the pinhole is mounted in. I'll test it again some time this week.