Get a use EM10 light enlarger meter from Ilford. You can most likely find one on Ebay. Pick a neutral gray area in the print you like, and use the meter to record the light level. Then change the enlarger distance, and change the light until you get the same exposure number. If the first print is going to small, stop the lens down, so when you move the enlarger head up, you can open the lens aperture, and get the same number on the meter, keeping the time the same. Forget the 8th grade math! Steve Harris www.harrisfoto.com On Sun, 2005-06-26 at 09:59, howard wrote: > In practice I find the only safe way to get correct exposures for > varying size enlargements is to always make a test strip. Having got one > correct, that helps me to guess the approximate times if I make changes > to the enlargement factor, and so the next test strip always gives me a > starting exposure. > > H. >
