DIY Pinhole Camera

It's some years ago I made for the last time something with pinhole cameras. First I built the Dacora Obscura, which was the ultimative letdown. Just one picture was okay. Then I built some "pinhole lenses", which were really good, but the results weren't what I expected.
After these experiences I lost the pleasure to make more with pinholes.

But some days ago I found at Ebay a Zeiss Ikon Contina Ia (type 526/24) without lens and shutter, it was just the camera body and the old leather bag.

picture from the ebay seller

picture from the ebay seller

Because of this the camera was very cheap and instantly when I saw it I had the idea to make a pinhole camera out of it. Therefore I bought it. 
The Contina arrived today and I attached an old 48mm Rollei lens cap to the camera. The lens cap perfectly matched. After this I measured the focal length, which is 45mm and used the pinhole size calculator to determine the diameter of the hole. Then I made with a needle a tiny hole in the middle of the lens cap.

Focal length: 45mm
Diameter: 0.283mm
fStop: 159
Image circle: 86,4mm 

I hope I can soon show photos taken with this new DIY pinhole camera.