So you are not using the sound hole and will be making a hole for the
pin hole where the neck attached. I would think that the resulting image
would look somewhat like what I get with my oatmeal box cameras. The
problem will be that on the curve of the lower half of the guitar body
the curve under cuts the light so you will get shadows and the upper
ends of paper will be much closer to the pinhole and will be much darker
then what is imaged on the bottom. I would think it might be easier to
make this shape camera out of a guitar case with the neck part cut off.
It would allow you to have a large flap and clasps for sealing it up.
Good luck.
--
Chris Peregoy | http://www.gl.umbc.edu/~peregoy | http://imda.umbc.edu/