A few of us have pinhole cameras and may already know about this, but just in case, I thought I'd post it - this Sunday 28th April is "World Pinhole Day" http://www.pinholeday.org/
I've not participated previously, but I'm hoping to give it a try on Sunday for the craic. I'm trying to think up a few suitable locations I could get to. I'm also wondering what the best exposure rating might be for a few shots from Hill 16?!