Argenticien
Dave
Greetings all. I thought I'd share a process that I did, in case useful to others. Our local photo group here is planning an outing on Worldwide Pinhole Photography Day (27th April) so I thought I'd better get ready. This is my first pinhole; why start small? thought I, and set about adapting a Speed Graphic.
First I removed the 135 mm Optar (my only lens) from its lens board, then traced that onto scrap mat board:

After cutting it out with an X-Acto knife, I had this:

I measured to find and mark the center, then blackened the back to slightly reduce light bouncing around back there:

At this point, I mounted the board on the camera, took it into a dark closet, and shone a flashlight/torch around the edges of the board. It leaked light, so I needed light seals. My first try was with civilian green felt, the kind meant to stop the rough feet of sculptures, tchotchkes, etc. scratching table-tops. It proved too thick, so the board would not fit under the clips. What you're seeing here is actually my second attempt. I used 1 mm thick Jon Goodman seals. (I had hoped to avoid consuming the good stuff, but it was necessary.)

Left: win. Right: fail --

You can see, maybe, that Jon's 1 mm stuff is thinner:

This time, the mat board fit under the camera's clips. On to the actual pinholery... [Continues...]
--Dave
First I removed the 135 mm Optar (my only lens) from its lens board, then traced that onto scrap mat board:

After cutting it out with an X-Acto knife, I had this:

I measured to find and mark the center, then blackened the back to slightly reduce light bouncing around back there:

At this point, I mounted the board on the camera, took it into a dark closet, and shone a flashlight/torch around the edges of the board. It leaked light, so I needed light seals. My first try was with civilian green felt, the kind meant to stop the rough feet of sculptures, tchotchkes, etc. scratching table-tops. It proved too thick, so the board would not fit under the clips. What you're seeing here is actually my second attempt. I used 1 mm thick Jon Goodman seals. (I had hoped to avoid consuming the good stuff, but it was necessary.)

Left: win. Right: fail --

You can see, maybe, that Jon's 1 mm stuff is thinner:

This time, the mat board fit under the camera's clips. On to the actual pinholery... [Continues...]
--Dave