Hey All, I'm becoming very interested in pinhole photography and am considering desinging and building a 5x7 camera. Almost all of my applications would require a high shutter speed (of say 1/125) so I'm wondering if decent exposure at this high shutter speed is possible? Getting a shutter to work that fast shouldnt be a problem, as I'll modify a shutter system from an old SLR and fit it to the pinhole (I'm a fitter machinist by trade, so I like building/destroying things) I'm just woried that with such a high shutter speed that it wont expose the negative enough. I was thinking of using Ilford HP5 400asa 5x7 Sheet film. Pushed if nessessary. Is this at all possible?