Actually, I first modified a camera body cover with a pinhole, following the general instructions on the Internet. I tried it out several times on both my Canon 300D and XTi. The results were very disappointing. I did three different sized pinholes with no apparent improvement. I believe the AI in the camera might have had something to do with it. Putting one of these pinholes on a Nikon digital body cap had much better results. I have deleted all of the images taken with it.
Then I picked up a Yashica A TLR from my favorite camera store and went at it. I removed the taking lens and either unscrewed or destroyed the lenses init. One was cemented in place and was removed with a punch. This left the shutter and the aperture blades intact. I then went to the local auto parts store and bought a set of feeler gauges. Using the thinest, I made a pinhole with a quilting pin.
The test film came back with some nice images of a local library.
The construction project of the Yashica TLR to pinhole is covered in detail on the photographyhacks page.
