Change of Agitation - need advice for development time
I usually agitate the first 30 sec continuously, then every 30 sec two times.
I have a jobo tank with 470 ml in it.
Due the fact that the development time recently got pretty long (I changed dilution of ID11), I want to agitate the first minute and then 4 times every minute.
(old) Development time is 14:20 min.
Do you think I have to lengthen shorten the time with the new rhythm?
my practice and experience is to maintain the agitation routine regardless of the total time or dilution
How about increasing your temperature for development, like 75 degrees.
Maybe I'm missing something - - - but there must be a reason why you chose to increase the dilution of your developer. It would seem to me that in most cases, that would then dictate what you would want to do about agitation.
For example, one common reason to want to increase developer dilution is to compensate for higher contrast in the scene at the time of exposure. Increasing the agitation will increase negative contrast, so that would be exactly the wrong thing to do. In fact, to achieve optimum compensation with highly dilute developers, one might actually choose to decrease agitation, even to the point of what is sometimes referred to as "semi-stand" development in which the developing time is extended greatly (perhaps to an hour), but agitation is limited to the first few seconds and perhaps one short period about half-way through development.
Another common reason to want to increase developer dilution is to reduce the size of grain. Increasing agitation tends to increase grain size and would again not be appropriate.
No. I already increased ID11 from stock to finally 1:2.
I am pleased with the result. I have the optimum, but still want to change agitation freuquency.
Now, I have the 14.20 min., but with 30 sec agitation.
I want to reduce just to do some minor things between agitation. Like prepare the stop and fixer...
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If that's all you are looking to do, just interrupt your cycle for a few seconds and do it. If you miss one or two agitation rounds, it likely won't matter.
Four times a minute, including the rap on the bench to loosen bubbles, along with the initial continuous minute. . .that's pretty labor intensive!
Increasing the agitation from 2 cycles a minute to 4 cycles a minute is not likely to decrease developing time a lot. My guess would be 5% decrease in time, 10% decrease being unlikely. The rule of the thumb for continuous agitation is to decrease time 10-15% or so.
If you're happy with the results don't change it. All modifications change the results.
This is also true for changing the temperature. However, using a higher temperature is likely to affect developing time much more than the change in agitation you sugested.
If you simply want to increase the interval between agitations to enable you to do other things, then try the Ilford recommended agitation cycle of first 10seconds then 10 seconds every minute. This usually gives me time to do the kind of things you mention. However it may change the look of the negs slightly but in my experience having used both your current method and the Ilford method the difference should be small.
harri, you were right. Not much impact.
I now develop HP5 ASA between 250 and 320 ID11 1+2 with 15:00 min, first minute and then every minute 10 sec.
I will make my first prints of the first roll this wekend. So the results will be posted next week, I guess.
Isnt Ilford technique first minute continuous agitation?