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We test for reciprocity effects by constructing and analyzing film curves, just as we do to determine exposure and development information. Briefly, the involves photographing a masked step tablet taped onto a fluorescent tube. We use 5 exposures: 1/10 second (using the shutter), 1 second (also a shutter speed) with an ND 1 filter, 10 seconds with an ND 2 filter, 100 seconds with an ND 3 filter, and 1000 seconds with ND 1 and 3 filters, stacked. The exposure is the same in each case, at least theoretically.
The films are then developed to a "normal" average gradient, the curves are then run through the Plotter, using the 0.1-over-B+F speed point option. Exposure "failure" can then be read directly from the displacement of the speed points; development compensation is estimated from the average gradients of the various curves.
I believe a more complete descripttion of this process is due to appear in the upcoming issue of "D-Max." If you're not a subscriber contact info@viewcamerastore.com.
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