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IanBarber
9-Aug-2017, 06:06
I have a few questions about PyroCat HD Adjacency Effect & Minimal Agitation for those who use this process.

I know Steve Sherman is extremely knowledgeable on this subject and has produced a premium video which I am contemplating buying although my process is scanning and not darkroom printing.

According to an article I have been reading on the unblinkingeye website ..


Minimal Agitation — Minimal agitation consists of continuous agitation for the first 60 seconds of development, followed by 10 seconds of agitation every third minute. With this method a pre -soak of five minutes is strongly recommended to avoid the possible formation of bubbles on the emulsion. Minimal agitation has three desirable results: 1) it gives great apparent sharpness through the formation of maximum adjacency effects, 2) it provides a compensating effect, and 3) it provides increased emulsion speed.

When using this method with tank development especially when trying to achieve maximum adjacency effects do you still use a dilution of 1:1:100 or do you have to dilute the solution further.

sanking
9-Aug-2017, 06:35
....
When using this method with tank development especially when trying to achieve maximum adjacency effects do you still use a dilution of 1:1:100 or do you have to dilute the solution further.

When minimal agitation is used with tank development the typical procedure is to use a much weaker dilution of the developer, with total development times perhaps as much as 100% or more longer than those used with standard dilutions and intermittent or constant agitation.

For example, is normal development time for a specific film is 14 minutes with the 1+1+100 dilution, you might get the same contrast with minimal agitation with 1+1+200 at 30 or 40 minutes. That is just a ball park figure, not one based on any specific film and developer dilutions.

Sandy

Alan9940
9-Aug-2017, 06:38
If following Sandy's general method of minimal agitation (that is, 10 secs every third minute), then use 1:1:100. If following Steve's method of EMA, then you'll be using higher dilutions which will be derived at through testing. If you buy his premium video, he gives you good starting dilutions and timing for FP4+.

IanBarber
9-Aug-2017, 07:07
For example, is normal development time for a specific film is 14 minutes with the 1+1+100 dilution, you might get the same contrast with minimal agitation with 1+1+200 at 30 or 40 minutes. That is just a ball park figure, not one based on any specific film and developer dilutions.


Thanks Sandy


If following Sandy's general method of minimal agitation (that is, 10 secs every third minute), then use 1:1:100.

Thanks Alan, I have also added this to my notes

IanBarber
9-Aug-2017, 10:12
For example, is normal development time for a specific film is 14 minutes with the 1+1+100 dilution, you might get the same contrast with minimal agitation with 1+1+200 at 30 or 40 minutes. That is just a ball park figure, not one based on any specific film and developer dilutions.

Just been doing some maths on this for my Paterson (1000ml) Tank which allows me to develop 4 sheets of 4x5 at once

Using the 1+1+200 dilution, I will need PartA = 5ml + PartB =5ml + 990ml of water

Using the above, can I develop, 1, 2, 3 or 4 sheets at the same time without changing the dilution ?

Ian

Alan9940
9-Aug-2017, 10:58
Ian,

As a point of reference for your experimentation, I use 8A + 5.3B + 1,400ml water (1,400ml total volume) of Pyrocat-HD @21C to develop 10x8 Foma 100 in my homemade tanks. Film exposed at EI80. Development process is: 5 min pre-soak, 2 mins initial agitation, then 6 x 3(20); tank sits for 6 mins, then 20 secs agitation, then sits another 6 mins, etc, for 3 cycles. Following development, I pull the film from the tank and stop/fix in trays. Stop bath is a very dilute concentration of 3ml 28% acetic acid to 1,000ml water.

FWIW, my exposure index for the Foma 100 and this development procedure has been tested using densitometer measurements, but is such that the highlight density comes in at a much lower value than what one would typically strive for when doing straight silver printing on VC papers. I use a split-grade filter printing method somewhat similar to how Steve prints. However, you can obviously develop the film to whatever contrast index you need for your equipment and preferred printing method.

Have fun!!