According to mrpinhole.com the perfect pinhole size for my suitcase camera is 0.42mm! To achieve this I invested in a set of minute drill bits and an Archimedes drill. Bad technique with my new tool ended with me frustratingly bending the 0.4mm drill bit. However I was more successful second time round and produced a lovely 0.45mm pinhole in a brass sheet gifted by my father.
At lunchtime today I loaded my camera and set off for Keptie Pond. This time I did take a meter reading however half way through my 25 second exposure the sun came out. Not that I am disappointed. The exposure may be incorrect but the image is still lush!
Focal length - 99mm
Pinhole size 0.45mm - f220