Pyrogallol based developers, such as PMK or 510 will work with metaborate but pyrocatechin based developers, such as pyrocat, need higher PH than metaborate but should work with carbonate or hydroxide.
Cheers John. I often vary the first bath dev time depending on the subject and/or lighting but I always stick to 4 mins in bath2. My bath2 is always Sod Tet (Borax) but I mix it 14g per litre as it isn't quite as active as the Metaborate type. I still haven't tried the FX55 - I think I'm just happy with what I already use. As always - best wishes from the Rhondda.
@@PictorialPlanet I have my own version - modified from Thornton's to better suit our local tap water supply ...... 6g Metol + 85g Sulphite per litre. It's surprising how tap water can vary. I'm originally from Lancashire and moved to Wales nearly forty years ago. I had to modify ALL my formulae and process times to correct my results here. I'm not moving again!!! Please keep the videos coming. Diolch!!!
Thanks for another great video. Is the 3/4 of the developing time, the published time, or your personal developing time as worked out in an earlier FX-55 video?
Grain (and film speed with FP4) seem so impressive with FX-55. I have all the chemicals and will surely try it out once my D76 canister runs out. Have you tried how's fogging with old expired film or compared to other developers generally? pH of 1% metaborate solution is more alkaline (pH 11.0) than borax (about 9.3 at 1%) but I guess the amount of developer in film is probably the limiting factor and activating something running out more may not matter. I've not tried any two bath developers so this is an educated guess only. Sometimes the reality gives surprises. Sodium carbonate (washing soda) should give a similar pH of about 11 too at 1% or so diulution. I guess I'll try that out some day (washing soda is more available than borates, especially in EU).
Being cost conscious, Can the Bath B be used multiple times? Your prints look 10x8, I would not expect to see any grain with FP4, have you tried a crop enlarged?
I would think bath B could be reused many times. I haven't tested it but would think at least ten. My grain estimates come from examining the grain while enlarging. FP4 is my day to day film and I'm experienced in what this film can give in many developers.