2-bath question

[Harry Lime]

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.

Bath 'A'
4 min
agitate gently, once every minute.
Save this solution, by pouring it back in the 'A' container.

Question:
a) This solution is recycled, correct?
b) What is the exhaustion rate of this solution? About 15 rolls for 1 liter?

Bath 'B'
4 min
Agitate once, tap for bubbles

Question:
c) Do I discard solution 'B' after it's use or recycle it for about 15 rolls per 1 liter?


thanks

 

[Ian Grant]

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 ?

Ian

 

[Harry Lime]

Bath A
Metol 6.25g
Sodium Sulphite 85g
water to 1 liter

Bath B
Sodium Metaborate 12g
water to 1 liter


This is my first attempt with a 2-bath developer, so this is virgin territory for me. ;-)

 

[jim appleyard]

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.

 

[Harry Lime]

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.

This could be the beginning of a beautiful friendship.

 

[el wacho]

hi Harry,

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.

 

[jim appleyard]

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!

 

[Harry Lime]

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?

thanks again.

 

[el wacho]

hi Harry,

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.

 

[JohnFinch]

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.

John
pictorialplanet.com

 

[Harry Lime]

Thanks guys.

el wacho, I'll look up fx4.

John, how clear is the film base around the sprockets of your developed and dried negatives?
Mine are looking a little dense at 4min (circa 20 C) in each bath. Maybe I should bump up the time in bath B a little?

thanks

 

[Alan Johnson]

Mine is now 12 months old, the 'A' kept in a sealed bottle topped up with inert gas. It still works OK. I get EI 64 sun/shade with Delta 100.
www.awh-imaging.co.uk/barrythornton/2bath2.htm

 

[JohnFinch]

John, how clear is the film base around the sprockets of your developed and dried negatives?
Mine are looking a little dense at 4min (circa 20 C) in each bath. Maybe I should bump up the time in bath B a little?

thanks

There's very little base fog at all. They are about as clear as you get. I find the developer is very clean working.

John
pictorialplanet.com

 

[Harry Lime]

hi Harry,

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.

Thanks for the answers, but a few more questions:

If I read this correctly; are you saying that because Thornton's 2-Bath uses methol, that I won't get 400asa out of Tri-X?

How do you then get a speed boost, if there is Metol in fx4? Probably because the amount is so small and it's mainly acting as a solvent?

Crawley's fx4 (as a 2-bath)

Bath A

Metol 2.5g/l
Hydroquinone 5g/l
Phenidone .025g/l
Sodium Sulfite 80g/l
Potassium Bromide 1g/l

Bath B
12g/L Borax


thanks for all the help. I'm just venturing in to mixing my own solutions. I like it.

 

[el wacho]

hi Harry,

i suspect that it's the phenidone/hydroquinone combination that yields the better than box speed results. there are other factors such as agitation ( from what i understand, shadows are established in the first minute or two of a development regime ) etc. as far as i know, the metol doesn't act as a solvent, not inthe sense that the sodium sulfite does. hope this helps.

 

[Harry Lime]

thanks. I'll give fx4 a try

cheers

 

[dancqu]

thanks. I'll give fx4 a try cheers

Ever consider 2-bath with water the second?
Back and forth and back and forth. Perhaps a
stock D-23 A-bath. Tempted myself. Dan

 

[Harry Lime]

Interesting observation. I'm 8 rolls in to my second 1 liter batch and noticed that I get fuller developed negatives, if I only agitate once at the beginning of bath B for 3 seconds, followed by a very gentle second agitation halfway through development (3:30 min total).

With more agitation (first 5 sec, 5 sec/minute) the negatives were coming out less developed.

Over the past few days I read some where that too much agitation can literally rinse the absorbed developer out of the negative. There could be some truth to that.

In any case I'm very impressed by the results. The Tri-X (400) negatives display good acutance, but are not overly grainy. Highlights and shadow detail are impressive. I did a test and deliberate exposed a sunset shot incorrectly by +/- 2 stops and got a useable negative from each exposure.

Best of all the results are very consistent from roll to roll and the process is basically idiot proof. It's also nice to have a little more slack in terms of development temperature.

I'm sold.

 

[el wacho]

great stuff Harry. glad to hear its going well.

which A bath are you talking about?

 

[Paul Verizzo]

Great work, Harry!

Interesting observation. I'm 8 rolls in to my second 1 liter batch and noticed that I get fuller developed negatives, if I only agitate once at the beginning of bath B for 3 seconds, followed by a very gentle second agitation halfway through development (3:30 min total).

With more agitation (first 5 sec, 5 sec/minute) the negatives were coming out less developed.

Over the past few days I read some where that too much agitation can literally rinse the absorbed developer out of the negative. There could be some truth to that.

In any case I'm very impressed by the results. The Tri-X (400) negatives display good acutance, but are not overly grainy. Highlights and shadow detail are impressive. I did a test and deliberate exposed a sunset shot incorrectly by +/- 2 stops and got a useable negative from each exposure.

Best of all the results are very consistent from roll to roll and the process is basically idiot proof. It's also nice to have a little more slack in terms of development temperature.

I'm sold.

What did you determine was the best ISO for Tri-X?

Great observation about loss of image with excessive agitation. I advocate just a hard rap or two on the countertop and then let it sit, unagitated for two baths. Anything else partially or completely negates what a two bath is for.

 

[Harry Lime]

What did you determine was the best ISO for Tri-X?

I'm shooting Tri-X at boxspeed, but in practice I tend to expose it more like a 320 or 200 asa film in practice. So, I'm usually shooting it at f16/250th, instead of f16/500th in broad sunlight. Not, that there is any sunlight in London at the moment...

Great observation about loss of image with excessive agitation. I advocate just a hard rap or two on the countertop and then let it sit, unagitated for two baths. Anything else partially or completely negates what a two bath is for.

Yes, yes. I agree. I gave it a super gentle twist halfway through bath B, to fend off bromide drag, but I agree that in this case less really is more.

 

[Harry Lime]

great stuff Harry. glad to hear its going well.

which A bath are you talking about?

Thornton's 2-bath

 

[Paul Verizzo]

Must agitate, must agitate, must

Yes, yes. I agree. I gave it a super gentle twist halfway through bath B, to fend off bromide drag, but I agree that in this case less really is more.[/QUOTE]

Ha ha, yes, it's hard not to do what we've done for years, isn't it? I agree that your reasoning was a good cautionary one. Try a roll w/o agitation and see if you get drag.

 

[Harry Lime]

>Try a roll w/o agitation and see if you get drag.

will do.

I would also like try try different versions of bath B to control contrast.

 

[dancqu]

I would also like try try different versions of
bath B to control contrast.

About a teaspoon of bicarbonate of soda.
A bath then B bath then A bath and back
to B. Or visa versa. Use A very dilute
as a one-shot. Dan