Barry Thornton's two-bath question about time and temperature

[Andrew O'Neill]

Barry Thornton 2-Bath is quite remarkable. I use it mainly with P30, (although I have used it with XRAY sheet film quite successfully). I find it works quite well with P30, a contrasty film. EI 32 gives me nice, open shadow detail. In bath A, the film is agitated constantly for the first minute, then 5 sec every 30 sec. Agitation is the same with bath B, although a bit more vigorous. 4 minutes in both A and B. I haven't yet played with the times, as I was quite happy with the results. I usually mix up 500ml and use it one shot. If I'm developing sheet film, then I'll mix up a litre. As far as temperature goes, I keep both baths at 20C. I've not experimented with temperature variations.
And...It's on my list to see whether or not it'll make a film developer for Alt processes...

 

[snusmumriken]

At 5 minutes in both Am and B, there's no way you should have ended up with underdeveloped negs. Five minutes in each is quite a lot for FP4. I suspect your chemistry may have been faulty (or you underexposed the film?).

I agree. It seems inappropriate to be so dismissive after one bad experience that was almost certainly self-inflicted. Chemically, BT2B isn’t that different from D-23 anyway.

 

[Romanko]

I used Finch's recommendation, FP4, 5 mins in each, the negs were way undeveloped.

I was very happy with FP4+ developed for 4 + 4 minutes in Barry Thornton's 2 bath developer.

but lately he seems to be making videos for the sake of making videos with questionable content.

I think John's videos are targeting beginner photographers like me. I like watching them and am learning a lot from John.

 

[snusmumriken]

Looking back over my last 30 rolls of FP4+, I see I've generally been doing the equivalent of 4.5 + 4.5 min at 21 deg C, but I vary it according to what's on the film (if I can remember), and which camera it came out of.

 

[-chrille-]

I developed 2 sheets of Fomapan 200 5x7 today in newely mixed Thornton 2-Bath and got strong coloration. Is this normal? Chemicals was mixed with deionized water and I let it sit for 24 hours before use.

However, the negatives turned out really well.

 

[Romanko]

I like the color of antihalation layer on Fomapan. Kodak Verichrome Pan was even nicer.
This is normal.

 

[retina_restoration]

I developed 2 sheets of Fomapan 200 5x7 today in newely mixed Thornton 2-Bath and got strong coloration. Is this normal? Chemicals was mixed with deionized water and I let it sit for 24 hours before use.

However, the negatives turned out really well.

This is normal for Fomapan, yes.This film has a very intense emerald green anti-halation dye in the emulsion which comes out in the developer. Quite normal.

 

[-chrille-]

Good to know, thanks

 

[snusmumriken]

As this is becoming quite a comprehensive thread on BT2B, I thought to share another tip. I hope this is useful to someone.

As already mentioned above, one can use a mixture of borax and sodium hydroxide in place of Kodalk (sodium metaborate), the mixture being chemically the same thing once in solution. The equivalent amounts for Bath B of BT2B would be 1.8g sodium hydroxide and 8.4g borax. I think it's a pain to weigh such odd amounts each time, so I keep a shelf bottle containing 1-Molar sodium hydroxide: in other words each litre contains the gram-equivalent (40g) of the molecular weight (40).

My Bath B then becomes:
approx. 700 ml water
45 ml 1-Molar sodium hydroxide
8.5 g borax
water to make 1 litre

[I add 2g Calgon to the water first when mixing both Bath A and Bath B, because I live in a hard water area.]

If you are considering using sodium carbonate in Bath B instead of metaborate, I noted from somewhere (probably here on Photrio) that, weight-for-weight, carbonate has about twice the activity of metaborate.

 

[pentaxuser]

I used Finch's recommendation, FP4, 5 mins in each, the negs were way undeveloped. Don't think I'll bother with it again, happy back with D 23. I used to like Finch but lately he seems to be making videos for the sake of making videos with questionable content.

Well his "Friday tips "videos are probably somewhat obvious to those such as you and I who are frequenters of forum such as Photrio but I suspect he feels his main audience are not such people and he is probably right

He also tries things out such as his recent experiments with FX55 and sometimes not much comes of those experiments but what I like is the clarity and honesty of his explanations and the fact that when nothing much happens he still releases the video in question

pentaxuser

 

[What About Bob]

I developed 2 sheets of Fomapan 200 5x7 today in newely mixed Thornton 2-Bath and got strong coloration. Is this normal? Chemicals was mixed with deionized water and I let it sit for 24 hours before use.

However, the negatives turned out really well.

Your colors are vibrant! They look like Gatorades or Vitamin Waters.

My Part A comes back out looking like a champagne, golden rose, color and my Part B comes back as a lemonade looking solution.

 

[What About Bob]

I have done five rolls of film so far using two-bath and I must say that I am very pleased with the results that I am getting. I do not see any issues with using slightly higher temperatures with this process. My apartment complex is a major heat trap, temperatures can soar rather high. The highest so far that I have developed was at 76.1F/24.5C and the frames look tonally awesome and sharp! I was afraid that the highlights may blow out because of the higher temperature and with no adjustment of time. I was doing temperature control until I stopped a little while ago, before I started Barry Thornton's process. It is a headache with temperature control and dealing with extra containers, ice cubes, limited space, monitoring, yadda yadda that it was taking the fun right out of the process and was a huge delay for me to get things going.

I was a control freak when it came to temperature for the longest time until I said to myself: "let me try this and see what happens". Before I did the two-bath process I was using time alteration by using the calculator from the MDC page for D23 at 1:1 and it worked great. When I finally got to using two-bath I realized there wasn't a compensation to use that would be really doable because times were really on the short end and I was reading to just use the prescribed times and do not deviate from 68F/20C. Again, I heard that voice saying to me: "let me try this and see what happens".

I have processed Kentmere 100 and 400 at 76.1F/24.5C, highest so far at this time, for 4 minutes and 5 minutes respectfully and I have to say that I don't see any negative issues, no pun intended. The grain structures look fine on both film speeds just like when I normally developed with D23 1:1 with slightly more sharpness which is probably due to the slightly lesser sulfite in the mix and my agitation is lesser than usual, much so with the Part B: No inversion the first minute and then one slow and careful twist every minute.

 

[Romanko]

I am glad that Barry Thornton's 2 Bath works for you. It is a great developer. As you discovered it is more forgiving than "active" developers. Part A is a slow-working developer so a bit higher temperature and longer development time does not have much effect on contrast. Part B pretty much works "to completion" before all the carry-over metol is exhausted. So once again not that sensitive to temperature and time.

 

[-chrille-]

Your colors are vibrant! They look like Gatorades or Vitamin Waters.

My Part A comes back out looking like a champagne, golden rose, color and my Part B comes back as a lemonade looking solution.

Just a quick update. Went down to the darkroom to develop some more 13x18cm sheets to find that the lovely color in bath A has disappeared after 4 13x18cm sheets. Not shure what is going on(maybe som oxidation?), but the developer still gives me beautiful negatives

 

[snusmumriken]

Beautiful colours! Glad to know the solutions work OK nevertheless.

 

[Molte]

Thank you for an informative thread. I will be using bath B as one-shot when I am back and get to develop film again.

 

[Andrew O'Neill]

I developed 2 sheets of Fomapan 200 5x7 today in newely mixed Thornton 2-Bath and got strong coloration. Is this normal? Chemicals was mixed with deionized water and I let it sit for 24 hours before use.

However, the negatives turned out really well.

Is that from the film's AH layer? I pre-wash before film goes in the part A.

 

[retina_restoration]

Is that from the film's AH layer? I pre-wash before film goes in the part A.

Andy, why would you pre-wash the film when using a divided developer? The whole idea is to get as much developer absorbed into the emulsion before it comes in contact with the accelerator, and pre-wetting the film is going to mean less developing agent getting onto the emulsion. I mean - if that's working for you, that's fine - but its contrary to the technique of a divided developer.

 

[bags27]

Andy, why would you pre-wash the film when using a divided developer? The whole idea is to get as much developer absorbed into the emulsion before it comes in contact with the accelerator, and pre-wetting the film is going to mean less developing agent getting onto the emulsion. I mean - if that's working for you, that's fine - but its contrary to the technique of a divided developer.

I've always prewashed Thorton 2-bath, thinking is that it "opens up" the film, making it more "receptive" to absorbing the developer. But note my non-scientific descriptors: I'm basing this on nothing more than instinct. It may well be the opposite: that by absorbing water, less developer gets absorbed.

 

[Andrew O'Neill]

Andy, why would you pre-wash the film when using a divided developer? The whole idea is to get as much developer absorbed into the emulsion before it comes in contact with the accelerator, and pre-wetting the film is going to mean less developing agent getting onto the emulsion. I mean - if that's working for you, that's fine - but its contrary to the technique of a divided developer.

It's working just fine for me

 

[-chrille-]

Two more 13x18cm sheets and the developer is once again colored like it was some kind of radioctive waste product

Anyone here tried Thorntons 2-bath with HP5+ pushed 1 or 2 stops?

 

[What About Bob]

Two more 13x18cm sheets and the developer is once again colored like it was some kind of radioctive waste product

Anyone here tried Thorntons 2-bath with HP5+ pushed 1 or 2 stops?

View attachment 370515

I would be curious to see what others have for colors.

On my next film run I will take a picture of my Kentmere colors. A rosy-golden champagne color for Part A and a mild lemonade color for Part B. My guess is that my colors should be a little bit more saturated after another development run but not as vivid as like what you have going on. There should be a page on here for posting different films and their colors in these baths. Could call it: "Barry Thornton's color swatches library thread"

 

[What About Bob]

As I promised. Here are the Kentmere colors.

Looks like the Part B lemonade went more toward lemon-limeade after the second run.

My colors are not that exciting. Champagne or lemon-limeade, anyone?

 

[Alex Benjamin]

However, Bath B should only be used 3 or 4 times before making a new bath, for the reasons stated (Bath B becomes more and more active as Bath A is carried over).

This is not what Barry Thornton said. I quoted him in this thread :

Thornton Two Bath & contrast control

For those who use TTB regularly but don't have Thornton's book Edge of Darkness, there are some interesting notes in there on contrast control when using the developer. I find them useful, as, with the heat of summer, I've noticed a slight increase in contrast (albeit with no blown highlights)...

www.photrio.com

 

[retina_restoration]

This is not what Barry Thornton said. I quoted him in this thread :

Thornton Two Bath & contrast control

For those who use TTB regularly but don't have Thornton's book Edge of Darkness, there are some interesting notes in there on contrast control when using the developer. I find them useful, as, with the heat of summer, I've noticed a slight increase in contrast (albeit with no blown highlights)...

www.photrio.com

OK. But the fact remains that Metol and sulfite accumulate in Bath B the more it gets used. That has a non-zero effect. Maybe that doesn't matter much in practice, but for consistency I prefer to limit the number of times I use Bath B to about 4.