Color film for VERY long pinhole exposures?
I am new to this group and have an interesting question, though I might offend some because a computer is involved.
I am taking some "solargraphs" by the method described by Justin Quinnell, who has been discussed here as well (google him for more details). A piece of black and white photo paper is exposed in a pinhole camera for days to months exposure. When the film is removed from the camera, a VISIBLE negative image is recorded on the paper. The paper is then scanned quickly with a digital scanner and further processing is done on the computer. It's really an ingenious technique.
One of the neat things about it is that despite using black and white paper, some COLOR is rendered by the process. After negation, the sun is yellowish and the background often a blue tint. I doubt there is much spectral information recorded, but perhaps the color is proportional to exposure. If someone could explain the physics behind the process, that would be welcome.
But my question is this: What would happen if I were to use COLOR photographic paper as my "negative"? Does it work in the same way as black and white paper does? I presume it is much faster, but after a few days exposure, would there be a visible image recorded that could be scanned if only once? Does color paper exposed to light even get dark?
I'd like to see what folks think before investing in a box of color photographic paper. Even on e-bay it's getting expensive. But with fall colors coming out, it would be nice to get some subtle hints of color in my pinhole shots.
Thanks, and I look forward to your replies.