every 30
If you don't mind me jumping in here, could I ask for clarification on a minor point? When it is said "every 30 seconds", are we talking about the sweep second hand being on the 12 and then at the 6, or setting a timer to go off after 30 seconds, then agitate?
If agitation is done on the 12 and 6 , the result is 20 agitations in a 10 minute period, for example, and if agitating for 10 seconds each time this results in 200 seconds of agitation during the 10 minute developing period, or in other words, agitation would be taking place 20 seconds out of every minute, basically one third of the time (200 seconds out of 600 seconds). Just using some round numbers here as an example.
The other method of "After" 30 seconds gives far less agitation for the 10 minute period. In this case, each subsequent one starts 30 seconds after the 10 second agitation is complete, and so on. Any other numbers plugged in will not change the question.
This was pointed out to me by a knowledgable person, and I've been wondering about this when I read of agitation methods. He pointed out the potential to over agitate the film. Is there a standard meaning for "every 30 seconds"? I don't think I've see it in my reading. He explained to me I should wait 30 seconds, then agitate.
Thanks for any clarification. If this is totally obvious and dumb, I apologize in advance for interupting.
Jeff
Sounds good to me. 2 twisty, GENTLE, inversions every 30 seconds, and none the last minute. Yes, vary which way you twist it each time, but in the instances when I've forgotten to do that, everything turned out fine. The key, for me anyway, is to keep the inversions gentle. I do give the tank a good, strong rap on the counter every other inversion and have no issues w/ bubbles on the negs.