Hi Klainmeister I like it!.. have you posted any of the 16x20 results?
I have made some of my own pinhole cameras, but by far, prefer the commercially available ones. Maybe some day this will change, but many of the available cameras are very beautiful pieces to work with in their own right.
i buy laser-shot pinholes frompaul koza @ munich university, very clean and accurate.
If I had the necessary skills and tools to make one I would do it. I think the satisfaction from having a home made one is that much greater. Alas, I do love my Zero Image 45. It has all the things that I would probably be too lazy to make on my own like the interchangeable pinhole sizes and zone plates and I can adjust focal length. That alone was worth it in itself as I don't shoot a lot of very wide shots. Flexibility was what sold me on Zero Image, and that was also its appeal over the mighty Harman's Titan. Although Titan 8x10 system sounds very appealing.
Have fun building and show us your progress! :)
Hmm (since this popped up again) -- in my earlier answer I interpreted the question as being about the actual pinhole plates rather than the entire camera. Stepping up the hierarchy to the entire camera, I've been a little less DIY -- sort of. A pinhole lens board for a 4x5 press camera was my first effort, a pinhole body cap for my Bronica SQ-A was the second. The third effort, in 2011, was a complete from scratch 4x5 (= UK 5x4 :D) except for using standard filmholders.
Almost everything I've ever done with pinholes is online for what it may be worth. I must confess to a few impure thoughts about something larger, but it probably won't happen this year.
The two samples he shows, drilled versus laser-shot, with the drilled one looking finer, got the same image size.
But they are actually apart in diameter by factor 2.5 or at its best 1,7, to the actual benefit of the "coarser" laser one...
I'm currently re-processing some of my pinholes from last year. Mid year I switched from a home made pinhole to a 'factory' made (some guy in Germany makes them with laser). I can see a clear difference in image quality.