Recently I’ve put a little time into trying out the old pre-exposure trick. Pre-exposure is basically just a double exposure where the first exposure is of an even, neutral surface. Ansel Adams explains it well in his book, The Negative. I’m having trouble writing someting clear at the moment.
Anyway, below are some examples. Notice the increase in shadow detail. I tried to pre-expose to zone I. My method was to first expose the film to direct sunlight through a plastic diffuser. This created a reddish hue in the shadows, which can be corrected later. I may experiment with some green gels or a light green filter at some point; this should create a more yellow tone in the shadows.
As for the base exposures, the first images had the tree trunks placed purposely in about zone II to test the pre-exposure. The second set of images had the tree behind the Yucca tree placed at zone V, which was pretty much the proper exposure for the exterior. I wanted to see how much the pre-exposure would help in a case of total disregard for the shadow area.
It appears that it’s harder to see the difference when the pictures are so small. The links go to my photobucket page for each. Hopefully, this is a useful post… And here is one more picture. I can’t remember the exposure for this one, but the brightest grass was exposed to zone VII. No comparison shot for this one though.