Two simple questions.
I just mixed up a batch of Barry Thornton's 2-bath developer and would like to verify that I properly understood the instructions for it's usage.
agitate gently, once every minute.
Save this solution, by pouring it back in the 'A' container.
a) This solution is recycled, correct?
b) What is the exhaustion rate of this solution? About 15 rolls for 1 liter?
Agitate once, tap for bubbles
c) Do I discard solution 'B' after it's use or recycle it for about 15 rolls per 1 liter?
Barry Thornton published and came up with a number of formulae.
Certainly more than one 2 bath Developer, so can you tell us which this is ?
Sodium Sulphite 85g
water to 1 liter
Sodium Metaborate 12g
water to 1 liter
This is my first attempt with a 2-bath developer, so this is virgin territory for me. ;-)
Harry, I am a frequent user of Barry's 2-bath and others. I've found that I get best results when I agitate the "B" bath the same as "A". I also get 6 rolls out each bath; yes, recycling the "B". Although Thornton says 15 out of "A", I dump after 6.
I also go 5 min. each bath. I feel that test rolls should be run these days when using a 2-bath; emulsions just aren't thick enough.
Thanks gents. I wasn't exactly clear which bath to dump and when.
I will recycle both solutions and keep a log to test how many rolls I get out of a liter of each.
Last night I developed a roll @ 4 min in each bath and they look very nice on the scanner.
I'm very impressed by the gentle roll off in the toe and shoulder. Grain is tight with good acutance.
I may want to figure out a way to lower the contrast. I read another article that suggests that the contrast can
be adjusted, by varying the amount of Sodium Metaborate in bath B. Apparently increasing the quantity, increases the negative contrast. Makes sense to me.
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i used a batch (A and B ) for over a year and it still proved consistent ( proof in the prints ) . of course the B bath is inexpensive ...
you can also tweek the sodium sulfite in bath A down to about 65g/L which starts to increase percieved acutance ( with a tad more grain - not in the range of a carbonate though ) without having to change bath B.
You can also use just a borax "B" bath to lower contrast. The divided D-23 series uses 10g of borax. The cool thing about divideds/2-baths is that you can have an unlimited number of "B" baths to control contrast.
Still, test rolls are advised!
One more question.
Has anyone here developed films above 400asa with this?
I mostly shoot Tri-X @ 400, which should be fine. But what about something like Delta3200 @ 1600?
I know that 2-bath developers (except for Diafine etc.) are usually not ideal for push processing, but at 1600asa, Delta is being pushed about a half stop, since according to Ilford it's 'true' speed is around 1200. Has anyone tried this?
Last edited by Harry Lime; 02-20-2008 at 06:34 AM. Click to view previous post history.
not really with metol alone as it loses anywhere between 1/2 - 1 stop of speed.
for 400speed films i use mr crawley's fx4 modified - without the borax in bath A and sod. sulfite lowered to 80g/L. i agitate in bath A (B bath is 12g/L of borax ) 4min in A and 2min no agitation in B - i consistently get 2/3-1stop gain. since it's mostly handheld i use sunny f16 and don't make notes but have been always happy with shadows. fx4 recipe can be found at jackspcs.com
hope this helps.
I have used Barry Thornton 2 Bath for years and recommend it often. I get a speed increase of about 1 stop with FP4+ and PanF+ (which surprised me).
I process at 24 degrees here in Florida and have found 3 minutes in each bath is good. Negatives are superb, sharp with a full range of tones. I have always used both A and B for the 15 films that Barry recommended and then I make fresh.
Barry actually designed this developer for modern thin emulsion films.