Quote Originally Posted by pentaxuser View Post
Claes. Just one more question. Is your recommended development time of 9 mins for Rodinal based on 20 degrees C? John Welton's recommendation on Ed Buffalo's site is 10 mins at 22 degrees centigrade and this is based on EI 80 instead of ISO125. As exposure at EI 80 suggests that a shorter development time might be better than at ISO 125, this suggests that I should maybe go for at least the full 10 mins which is what you use for RO9 even if this is at 20 degrees centrigrade.

However knowing your temperature will help me decide by how much I should maybe go beyond 10 mins. I think that based all of the above facts I should go for at least 10 mins and maybe 10% more which is 11 mins.

Thanks

pentaxuser
Yes, I have developed the film at 20 C.

I usually end up with rather short development times, compared to other users, when using Rodinal or R09 – so you might want to prolong development a bit. On the other hand – longer development can result in more fog…

You should also bear in mind that I don’t know what EI my father used when he exposed the old films I have developed. I know for a fact that he did not use a light meter (apparently he did not need one. He has left an archive comprising of thousands of very well exposed Kodachrome slides from the sixties and seventies). However, when he taught me the basics of B&W photography he advised me to base my exposures on the shadows and that it is usually better to use a lower EI than the stated speed of a B&W film. I can only presume that he followed his own advice.

Cheers

Claes