Quote Originally Posted by polyglot View Post
One more thing that may or may not be obvious from looking at the exposure curve falling off at the bottom end: this effect means you get increased contrast at exposure levels where reciprocity failure is an issue (anything over about 1s for traditional emulsions like Foma & Efke/Adox produce).
This is not always the case. See: http://www.phototechmag.com/index.ph...e/reciprocity/

There are several good threads on APUG on reciprocity failure, including this one:
http://www.apug.org/forums/forum37/1...sbehavior.html

Lee