I'm not sure why you would have an increase in grain when using your pinhole except perhaps it was due to a thin negative. This was the one that was exposed for a fraction of a second? I would try to get a better fix on your pin hole size. I use a comparator as described in Eric Renner's book, page 113 and 114 with the use of an enlarger to enlarge a metric scale. Then figure for reciprocity failure. I always try to make an accurate guess first with meter and calculations, then after gaining experience I can usually guess without these aids.
Katharine Thayer wrote: (snip) My inspection by loupe showed it was somewhat smaller than my smallest, which was a #10. For > calculation purposes I estimated it at .016 (I guess that must be > inches) but I have not actually measured it. All I cared at the time, in > my rush to make pictures, was it was smaller than the #10, which made > blurry pictures that everyone loved but couldn't be enlarged even a > little bit. > > My film of choice for color work is Fuji Reala, ISO 100, and I stayed > with this film for the pinhole work. > > Okay, so here's my problem: The exposures on this thing are completely > wacko. I shot four or five rolls of film to try to get a bead on the > exposures but never could come up with a reliable way to predict whether > the exposure would be even in the ballpark, which is why I gave up on it > for the moment, although I'm quite intrigued with the potential. > > The only image that came out exposed right at an exposure I estimated to > be near the right exposure, (8 seconds under high overcast) can be seen > at (I hope I've got this right): > -- Chris Peregoy | http://www.gl.umbc.edu/~peregoy | http://imda.umbc.edu/
