So a while ago I got this 500mm lens on craigslist for 5 bucks. Absolutely terrible lens. Anyways, it had a screwmount to Pentax K converter that came with it. A while ago I had the idea to unscrew the converter and try to make a pinhole with it. The other night I thought I'd try my idea out and this is what I came up with:
There was much experimentation done with the pin hole size. I glanced at some other sites and checked what they had done but really didn't want to go all out. Strictly some black sharpie and duct tape and paper. Here are a few shots with it: