reciprocity failure

[Thomas Bertilsson]

Poohblah - I am very pleased that my 'booksmart' analysis was completely wrong for your case, and that your negs came out fine. Note what you found and use it in the future, especially if you use Pan-F+ a lot.

- Thomas

 

[dancqu]

I made a contact sheet today and there was a slight
difference between the two frames,

So basically what you're saying is that i may have lost
some shadow detail, say in zone I or II, due to reciprocity
failure even if the midtones and highlights retained reciprocity?

That slight difference will be most noticeable in the least
exposed areas.

That is correct, some loss of shadow detail. That will happen
with border line light level scenes. If the entire scene lies within
the range of reciprocity failure then contrast will be high and minus
development may be needed. Dan

 

[Lee L]

Lee, the very next issue after that has the same article I posted in Unblinkingeye.com analyzing Howard's data by a different method than he used.

Patrick,

Yes, I should have mentioned that, especially when giving back issue information for Bond's article so both could be ordered at one time.

BTW, with respect to Dan's comments on increased contrast, as I mentioned in my earlier note, Bond found that the traditionally accepted reduction in development to counter increased contrast in long exposure negatives wasn't necessary with many of the newer films.

Lee