Originally Posted by
sanking
Weaker dilutions can be used but with any given film will result in less contrast. Of course, if you are developing to scan, which is the main reason this work flow is being promoted, less contrast does not make any difference, within reason. So a 1:20 dilution, or even weaker, may be used in place of 1:10. In fact, for some high contrast films, Efke 25, Rollei Pan 25, etc. a 1:15 or 1:20 dilution would be recommended as the standard since 1:10 might give too much contast.
The basic rule is that higher dilutions result in less contrast, but each film is different so there is no one magical dilution.
I have developed over a hundred sheets of 5X7 film and at least two hundred rolls of 120 film with divided Pyrocat-HD and have not seen any mottling or streaking once I got the technique down. I develop 5X7" film one sheet at a time in an 8X10 Beseler drum, on a motor base. The mechanism of development is such that the developer pretty much comes into contact with the film evenly and immediately. After development in Solution A, drain for 15 seconds, then begin Solution B. The basic procedure is.
Step One -- Five minute presoak in plain water. My water source if quite pure and I don't use distilled.
Step Two -- Five minutes in Solution A, then drain for 15 seconds.
Step Three -- Five minutes in Solution B, then drain for 15 seconds.
Step Four -- Wash for twenty minutes with distilled water.
Note that with rotary agitation I use a weaker dilution than with intermittent agitation, so instead of 1:10 which would be my standard for development of Acros in tanks on spiral reels with intermittent agitation I use 1:20.
With 120 film my procedure is as follows. Note again that the film comes into contact with both Solution A and Solution B immediately and completely.
Step One -- Five minute presoak.
Step Two -- Five minutes in Solution A. Drop the reels with the film loaded into the tank which has been filled in advance. Agitate vigorously for one full minute, then agitate vigorously for fifteen seconds every minute thereafter. Remove reels and drain.
Step Three -- Drop the film into a tank containing Solution B. Agitate vigorously for one full minute, then agitate vigorously for fifteen seconds every minute thereafter. Remove reels and drain.
Step Four -- Wash film for twenty minutes.
Please note that I have never advocated shuffle agitation with sheet film, or any other type of development that does not allow for the film to be immersed completely and all at once in the solutions.
Sandy King