Dear all, I have this Ombrux (Orig. Gossen) exposure meter with its table based on four Scheiner values (20°, 23°, 26° and 30°). I really want to use it to take pictures (becuase it seems to be working), but I can't seem to find a trustworthy site with a correct conversion table (to ISO)! All that I have consulted present different values! Does any have a good conversion table (or formula)? Thanks in advance, Sergio.