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8x10 inch pinhole test

Posted: Thu Dec 08, 2011 8:30 pm
by jon.oman
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:

Image

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:

Image

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/forum37/7679 ... ffect.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:

Image

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?

Re: 8x10 inch pinhole test

Posted: Mon Dec 12, 2011 6:02 pm
by JohnSR
That looks like work. What was the temp of the D-76?

Re: 8x10 inch pinhole test

Posted: Mon Dec 12, 2011 6:54 pm
by jon.oman
JohnSR wrote:That looks like work. What was the temp of the D-76?
It's all fun John!

The temp was 68 degrees F.

By the way, do you see the ghost of me sitting on the porch bench?

My legs stayed still, but the rest of me kept moving!