Advice on my Two Bath Developer

[GLS]

GLS, page 35, under Sodium and Potassium bisulfite.

Ah, I see. Yes this part of the book is speaking about general properties of ingredients, so I think the comments on buffering should be read in the more typical context of a monobath developer.

Most likely activity of carbonate there is reduced by acidity of metabisulfite as mention by Relistan.

To nitpick: it is not the metabisulfite per se which is acidic, rather the product of its hydrolysis (i.e. bisulfite).

 

[relistan]

I have been thinking about the next two bath developer formula I will try. I'd like a bit more solvent action. 2B-1 has quite high accutance to my eye, but also has well defined grain. In most films it looks very good but in some films it is not nice (to my eye).

I will use more sodium sulfite and some EDTA (which I have a lot of) as the solvents in bath A. The EDTA free acid will also help bring the pH down, meaning less citric acid is needed, and serve as a development accelerator. I am sure a small amount of tap water impurities will also get sequestered. Hopefully not too much iron. I am not sure how much is the right amount, so this will be a test. Too much will lead to fog.

Let's call it 2B-2. Here's what I think it will look like (not yet mixed):

Bath A

• Water — 700ml
  
• Sodium Sulfite — 60g
  
• Hydroquinone — 6g
  
• Phenidone — 0.25g
• EDTA free acid — 10g
• Citric acid to pH 6.6 (phenidone can develop above this)
  
• Water to 1L

Bath B

• Water — 700ml
• Sodium Sulfite — 10g
• Sodium Bicarbonate — 5g
  
• Trisodium Phosphate to pH 11
• Water to 1L

I am sure I will discover I did something wrong there when I actually mix it up so this will likely not quite be the final formula. I am trying to skip the carbonate because the stuff I have seems to have too much cruft in it and I have to filter the developer when I mix it. I'd rather not.

 

[Raghu Kuvempunagar]

I have been thinking about the next two bath developer formula I will try.

I'm sure this new round of exploration will be quite fascinating. It would be nice, when you do this, if you can also compare your results with those of Thornton's Two Bath.

 

[relistan]

It will be interesting to see if doubling the sulfite in part A has any appreciable effect on solvent action/graininess/sharpness. Of course it depends on the film. It may or may not also have a slight favourable impact on emulsion speed. I would probably try 100g. Traditionally speaking solvent action needs time (this was the mechanism of D-25 as a variant of D-23).

Indeed, I am unsure which bath the sulfite will make the most difference in. I am using on 60g because I want to see how much effect the EDTA has as a solvent (Haist says it is) and I figure more than 60g will disguise any contribution it might make. Maybe I should just use 35g + the EDTA.

I'm sure this new round of exploration will be quite fascinating. It would be nice, when you do this, if you can also compare your results with those of Thornton's Two Bath.

Thanks! Well, I have used that developer quite a bit in the past. I find it very fine grain, but below box speed, and low-ish contrast.

 

[Raghu Kuvempunagar]

Thanks! Well, I have used that developer quite a bit in the past. I find it very fine grain, but below box speed, and low-ish contrast.

Rudiger Hartung uses a variant of Thornton's two bath which has a bit of phenidone in bath A. He says this addition gives him better speed than the standard Thornton's.

He has an interesting technique for getting higher contrast with Thornton's - multiple rounds of two baths. After the end of the first round consisting of baths A and B, he gives the film a good wash and does a second round of Thornton's.

He's active on Facebook and has provided many examples with these enhancements.

 

[relistan]

Rudiger Hartung uses a variant of Thornton's two bath which has a bit of phenidone in bath A. He says this addition gives him better speed than the standard Thornton's.

He has an interesting technique for getting higher contrast with Thornton's - multiple rounds of two baths. After the end of the first round consisting of baths A and B, he gives the film a good wash and does a second round of Thornton's.

He's active on Facebook and has provided many examples with these enhancements.

Good idea to talk to him. It's funny you should mention that... https://www.flickr.com/groups/1505757@N20/discuss/72157697539499142/

Indeed, he has some very nice results from his Thornton 2 bath + phenidone.

 

[relistan]

Ok, today I mixed up experiment 2B-2 as follows, slightly different from what I proposed (but I can't seem to edit that now).

Bath A (pH 6.8)

• Water @ 40C — 700ml
• Sodium Sulfite — 60g
• Hydroquinone — 6g
• Phenidone — 0.25g (from 2.5% solution in PG)
• EDTA free acid — 10g
• Citric Acid — 4g
• Cold Water to 1L

Bath B (pH 10.95)

• Water @ 40C — 700ml
  
• Sodium Sulfite — 35g
• Sodium bicarbonate — 5g
• Trisodium phosphate — 30g
• Cold Water to 1L

pH was measured with my pH meter. It's not a super cheapy, and has reasonable reviews, plus I had to calibrate it. So, I think they are pretty close to right. I only ran a couple of leader clips through it today and will put some actual images in it tomorrow. Initial impression is that I can't see any difference between 3 or 4 mins in bath A, which indicates that no development is happening there. Bath B at 4 mins looks about right. There was a bit of blotchiness on the leaders when developed, but they have not been handled well so this may have nothing to do with the developer. Fomapan 400 and ADOX Silvermax density appears to be the same as with 2B-1 when comparing samples side by side. Which is interesting because some development happens in bath A on 2B-1. Again, this is eyeballed, no densitometer. Some tiny precipitate formed in bath B when developing. I would guess it's silver citrate because of the substantially more citric acid (8x as much). I will need to see if that is an issue. A better solution is probably to just use metabisulfite in A and skip some of the sulfite and all the citric acid. My guess also at this point is that the bicarbonate in B is not doing anything.

I got real numbers for pH for 2B-1: bath A is 8.05 and bath B is 10.70. So, 2B-2 has a bit higher pH in bath B and substantially lower in bath A.

 

[john_s]

I think you left out hydroquinone in the above post.

 

[john_s]

Also that seems like a lot of EDTA. How did you decide on that quantity?

 

[relistan]

I think you left out hydroquinone in the above post.

Good catch! Thank you. Fixed.

Also that seems like a lot of EDTA. How did you decide on that quantity?

Yeah, I'm not sure how much is right so this is an experiment. I'm intentionally trying out using it as a solvent. See post #67

 

[relistan]

This is what I was working from:

Obviously the fog is not desirable, but if the balance is right it might be interesting. And I have most of a kilogram left of it from bleach experiments. And I would think in a two bath the likelihood of fog would be lower if the EDTA is in A and the alkali are in B so only the transfer amount matters.

 

[relistan]

I put some test frames of Fomapan 400 through 2B-2 today at 4 mins A, mins B. They look good. No noticeable fog, but a little thin, which is usual for this film in two baths because it has such a thin emulsion. Maybe two trips through the developer next time to see how that works. Anyway, I will scan and post when they are dry. I am hoping for a softer grain than in 2B-1. We shall see.

 

[Alan Johnson]

In the 1930s I believe Curt Emmermann, author of "Leica Technik", invented the now discontinued Emofin which had the following properties:
(1) There was some development in part A (I have checked this). The part B was based on sulfite-carbonate. Maybe this is necessary to give maximum EI, IDK.
(2) It was based on metol, phenidone had not been invented at the time.
(3) Part A contained PPD. This is a solvent but since it is hard to get and can cause an allergic reaction it is not really of interest today.
Only (1) seems relevant , some development in part 1 may give higher EI.
Also, many of these 2 bath threads state that just developing for 4min +4min at any reasonable temperature and agitation will do.
I did not find this with my 2-bath developer MDS-1, I think the times, temperature and agitation have to be more closely monitored.
This is possibly the reason why many substitute formulas fail, inadequate research and instructions, at least for the case where there is some development in part A.
In this I note that Emofin came with quite a complicated instruction sheet.

 

[relistan]

In the 1930s I believe Curt Emmermann, author of "Leica Technik", invented the now discontinued Emofin which had the following properties:
(1) There was some development in part A (I have checked this). The part B was based on sulfite-carbonate. Maybe this is necessary to give maximum EI, IDK.
(2) It was based on metol, phenidone had not been invented at the time.
(3) Part A contained PPD. This is a solvent but since it is hard to get and can cause an allergic reaction it is not really of interest today.
Only (1) seems relevant , some development in part 1 may give higher EI.
Also, many of these 2 bath threads state that just developing for 4min +4min at any reasonable temperature and agitation will do.
I did not find this with my 2-bath developer MDS-1, I think the times, temperature and agitation have to be more closely monitored.
This is possibly the reason why many substitute formulas fail, inadequate research and instructions, at least for the case where there is some development in part A.
In this I note that Emofin came with quite a complicated instruction sheet.

Hi Alan, thanks for the commentary. Emofin sounds like a pretty cool developer from what you've said and what I've read.

Regarding development in A: yeah 2B-1 has a pH high enough to develop in bath A and I was definitely seeing more than box speed with most films. ADOX Silvermax 100 was good past EI 200 at least. I found that with some development in bath A you get pretty good control over density without multiple trips through the developer. And as such, I had different times for some films (e.g. 6+4 for ADOX HR-50). I used to be a user of Diafine and never found that you could get the best results from all films at the same times. They recommend 3+3 but I always ran Agfa APX-100 (original) at EI200 for 4+4 for my best results. Also yes, I agree. Temperature absolutely matters in my experience. I use 20C for everything.

I was encouraged by others to try to get the pH down in my two bath, so that's part of the experiment with this experiment. I was thinking about other solvents for A and decided to try out the EDTA I have.

I got the first results and some frames look quite good, others not so much. I got some weird blotchiness in solid areas in a couple of frames, which I think is an effect of over agitation. But it could also be some weird effect from the EDTA. I will have to try some more tomorrow. Initial impression from inspection is that it is definitely finer grained than 2B-1 but not massively so. So it may be that the extra sulfite is doing all the heavy lifting and the EDTA is not doing too much. Will have to try some more films, as well.

Here's one of the blotchy frames (Fomapan 400). The wall is a flat tan, and lighting was from the left. Note the sort of V shapes.

 

[Alan Johnson]

Two things about 2B-2 (post 70) :
(1) In Xtol they used only 1g/L DTPA so I suggest reducing EDTA to that level, otherwise have little idea of its effect, see example 1 $7 here:
https://patentimages.storage.googleapis.com/2b/eb/16/473305316ea7bd/US5853964.pdf
(2) The part A seems otherwise similar to the Diafine substitute formula posted on Photrio and the part B is similar to sodium carbonate given in this MSDS for Diafine part B (part A lists only "Trade Secret"):
https://www.freestylephoto.biz/pdf/msds/acufine/Diafine_Part_B.pdf
So the blotchy effect illustrated is not explained from the other ingredients.

 

[relistan]

Two things about 2B-2 (post 70) :
(1) In Xtol they used only 1g/L DTPA so I suggest reducing EDTA to that level, otherwise have little idea of its effect, see example 1 $7 here:
https://patentimages.storage.googleapis.com/2b/eb/16/473305316ea7bd/US5853964.pdf

https://patentimages.storage.googleapis.com/2b/eb/16/473305316ea7bd/US5853964.pdf

Thanks, Alan. Yes, in XTOL they are using DTPA as a chelating agent AFAIK. I say that because people commonly make developers with similar effect and leave it out entirely. I am trying to see what happens with EDTA as a solvent. According to the chart I posted from Haist, I don't think 1g/L will have any noticeable solvent activity. EDTA might be unsuitable for this at all if it is what causes that interesting blotchiness. It's not on all frames, though. But it does remind me a bit of an effect we saw when working on the Peroxide/Citric Acid/EDTA bleach. See @kentanghk's bleach D here: https://www.photrio.com/forum/threads/b-w-reversal-with-hydrogen-peroxide.180091/page-7#post-2364793. Note that while yes, this developer has two of those chemicals in it, it won't bleach without an oxidizer present (no peroxide). So yes, I suspect the amount of EDTA might be too much, but I will see if it was just the thin negative and not enough time, or too much agitation in B that was the culprit.

(2) The part A seems otherwise similar to the Diafine substitute formula posted on Photrio and the part B is similar to sodium carbonate given in this MSDS for Diafine part B (part A lists only "Trade Secret"):
https://www.freestylephoto.biz/pdf/msds/acufine/Diafine_Part_B.pdf
So the blotchy effect illustrated is not explained from the other ingredients.

Yeah, I agree with the blotchiness not being one of the other ingredients. I would think that without the EDTA this developer would be fine. I was hoping to do something maybe a little interesting. All of these developers are going to bear some resemblance if we are using the same chemicals. I started with 8g/L of HQ in 2B-1 (modeled on ID-67) but reduced it to 6 to see if this had an effect of reducing some edge effect that I have sometimes observed. Although I have also seen this in other two baths. Looking at the formula on Photrio I think you are referring to, I have got nearly twice as much sulfite in A and half as much in B. I have got citric acid instead of metabisulfite or bisulfite. I have got 0.05g more phenidone (which is a noticeable amount).

2B-2's part B uses trisodium phosphate like Diafine did in the 1980s, in part because my TSP is clean and my carbonate needs filtering. But also because I read about citric acid and DSP (note the "D") making a buffer that is used commonly by organic chemists: https://en.wikipedia.org/wiki/McIlvaine_buffer . I was thinking that this is one of the reasons Diafine probably used TSP originally. (I know TSP and DSP are not identical). And I was thinking this would possibly provide a very minimal buffer for development in B at a lower pH for a brief time, which I would think might give slightly softer working for a very short time. I am not sure if that will have an effect, so It was worth trying. I made a carbonate bath for 2B-1 but as I posted earlier, 2B-2's bath has a higher pH, and I don't think that carbonate and citric acid has this possible buffering characteristic.

 

[relistan]

I did some more experiments with 2B-2 and 2B-1 with 2B-2's bath B. Results show that on a blank leader there was mottling with 2B-2 and none with 2B-1 using 2B-2's bath B. So clearly the EDTA or EDTA/Citric acid is causing the mottling. I will do some further experimentation. However, on the frames where this did not occur, the results are quite nice. This is Fomapan 400 in 2B-2 for 4 mins A, 4 mins B. It is pretty crisp, but with a much finer grain than 2B-1. It may be that using EDTA but maybe at 5g/L is a better solution. I will keep experimenting.

 

[Trask]

In this I note that Emofin came with quite a complicated instruction sheet.

just for reference, I'm attaching PDFs of the English-language instructions for mixing and using Emofin, along with some MSDS-like information regarding the components -- noting that Part A itself is made of two separate envelopes of chemicals, while Part B is a separate (third) envelope of the accelerant mix. I'm also including a chart of Tetenal's recommended time/temp for various films, along with instructions on how to push Emofin.

These are the temperature/time correction factors:
18C - 1.2
20C - 1.0
22C - 0.85
24C - 0.75
26C - 0.6

You'll also note that I included, on the "push" page, a copy of the little self-adhesive stickers that Tetenal thoughtfully supplied with the developer to clearly mark the bottles as Part A and Part B. Nice!

Though outside the scope of OP's interesting efforts to create his own two-bath process, perhaps this info is nonetheless of some interest.

 

[relistan]

Over the last month I have made up a couple of new two bath developers and tested them. I now have one that is worth sharing. I'm calling it 2B-4, and it's a phenidone/ascorbic acid two bath. It has reasonable contrast, and appears to me to be speed increasing. I cannot precisely say by how much, but on Ilford Delta 100 it appears to be 2/3 of a stop or so. Here's the formula and an example image.

Some Notes
This developer is a true two bath developer unlike 2B-1. It does not do almost any development in the bath A. After 10 mins in A the film is a little darker but only a very small amount. As a result, it is quite a strong mixture in A. The normal time for the films I've tested appears to be 3 mins A, 3 mins B.

Gainer said the maximum performance ratio for phenidone to ascorbic acid was 1 to 40. I tried that, but I liked the results better with more phenidone, so this is 1 to 24. I slowly added more phenidone until I got to this point and was happy.

You might notice that I am using etidronic acid as a chelating agent to prevent the Fenton reaction destroying the ascorbic acid. I also used a fair bit more than was necessary for this purpose. I had read it may work as a mild silver solvent and so this was an attempt to leverage that. I suspect 1ml would have worked fine.

Lifespan
So far the mix for A has lasted almost a month in a sealed PET bottle and has processed about 5 partial rolls of film.

2B-4 Two Bath Developer

Bath A (pH 6.8)

• Water — 700ml
• Sodium sulfite — 35g
• Phenidone — 0.5g
• Ascorbic acid — 12g
• Potassium Bromide — 0.2g
• HEDP/Etidronic Acid ("Fotoplex 2") — 5ml
  
• Water to 1L

Bath B (pH 11)

• Water — 700ml
• Sodium sulfite — 35g
• Sodium bicarbonate — 5g
• Trisodium phosphate — 30g
• Water to 1L

Sample Image

The following is not art, it's just a hard scene with backlighting to see how the developer would handle it.

Ilford Delta 100 @ box speed
2B-4 for 3 mins A 3 mins B @ 20C

Note that the acutance is quite good. You can read some of the tiny text on the bottle of sodium thiosulphate.

 

[relistan]

@grain elevator You asked earlier in the thread about ascorbic acid two baths. Here is a good one!

 

[gorbas]

Congratulation Relistan!
So, how is Trisodium phosphate in relation to Borax, Kodalk or soda and other traditional alkalies in term of activity?
What is function of Sodium bicarbonate in B?
Nice amount of sulphite in B!

 

[ParkerSmithPhoto]

I know this is all fun to fool with, but once I set up a test subject (my bookshelf), exposed 120 film with a strobe consistent to 1/10 stop, developed the film in 4 different developers, and made 16" prints I realized there really isn't a whole lot of difference between developers.

If you want fine grain with classic tonality, use D-23.
If you want sharper grain with classic tonality, use Beutler's.
For something in between Beutler's and D-23, just substitute metaborate for the carbonate in the Beutler's formula.
If you want the sharpest negative possible (too sharp in my opinion), use Pyrocat-HD.

Even Rodinal wasn't significantly different than Beutler's in terms of grain, although the mid tones seemed to be a little too bright.

FP4 in Beutler's might be the most beautiful tonality I've ever seen in a negative; the grain is so tight it's almost not there, even at 16". HP5 in Beutler's has a grainier structure that is quite beautiful, too, and only appears about 1/4 stop less contrasty than FP4.

I'm sure you could easily reproduce these results with D-76, Diafine, Xtol, Barry Thornton's Two Bath, etc., all of which I have used extensively. In short, there's just not enough difference between them to justify trying to invent a new developer. Kodak and others spent millions of dollars and untold man-hours on this project, how can we possibly improve on that?

Lord knows the time I wasted until I ran these tests and proved it to myself. Just pick one developer and get to work. I'm a Beutler's Man now.

 

[grain elevator]

@grain elevator You asked earlier in the thread about ascorbic acid two baths. Here is a good one!

Great work, thank you! I will give it a try - as I don't have the chelating agent, I'm thinking leaving out the sulfite (might have impurities) and using demineralised water might make a somewhat stable bath A?

 

[Alan Johnson]

I know this is all fun to fool with, but once I set up a test subject (my bookshelf), exposed 120 film with a strobe consistent to 1/10 stop, developed the film in 4 different developers, and made 16" prints I realized there really isn't a whole lot of difference between developers.

If you want fine grain with classic tonality, use D-23.
If you want sharper grain with classic tonality, use Beutler's.
For something in between Beutler's and D-23, just substitute metaborate for the carbonate in the Beutler's formula.
If you want the sharpest negative possible (too sharp in my opinion), use Pyrocat-HD.

Even Rodinal wasn't significantly different than Beutler's in terms of grain, although the mid tones seemed to be a little too bright.

FP4 in Beutler's might be the most beautiful tonality I've ever seen in a negative; the grain is so tight it's almost not there, even at 16". HP5 in Beutler's has a grainier structure that is quite beautiful, too, and only appears about 1/4 stop less contrasty than FP4.

I'm sure you could easily reproduce these results with D-76, Diafine, Xtol, Barry Thornton's Two Bath, etc., all of which I have used extensively. In short, there's just not enough difference between them to justify trying to invent a new developer. Kodak and others spent millions of dollars and untold man-hours on this project, how can we possibly improve on that?

Lord knows the time I wasted until I ran these tests and proved it to myself. Just pick one developer and get to work. I'm a Beutler's Man now.

I agree with much of this but Kodak and others don't like to touch pyro or PPD or 2-bath and when they effectively closed the labs down , according to PE they were still working on new developers.I believe this continues in Germany particularly. It is not too difficult to see the differences between developers using quite simple equipment if you look closely enough:
https://www.photrio.com/forum/threads/scans-retain-developer-properties.156243/

 

[relistan]

Kodak and others spent millions of dollars and untold man-hours on this project, how can we possibly improve on that?

I honestly can't even engage with this way of thinking.

Great work, thank you! I will give it a try - as I don't have the chelating agent, I'm thinking leaving out the sulfite (might have impurities) and using demineralised water might make a somewhat stable bath A?

Sure, go ahead and try. But, this would be a totally different developer in that case. I have no idea what the results would be, but I suspect that you will not get the shelf life. You will definitely find a difference in the grain without the sulfite. It does make a difference, even at 35g/L.

Congratulation Relistan!
So, how is Trisodium phosphate in relation to Borax, Kodalk or soda and other traditional alkalies in term of activity?
What is function of Sodium bicarbonate in B?
Nice amount of sulphite in B!

Thank you! I'm very pleased with this result! It's different enough in output from 2B-1 to be a worthy of having both around. And not having to use hydroquinone is nice (it's harder to get here, and kind of expensive)!

Trisodium phosphate is quite a strong alkali, sitting between sodium hydroxide and carbonate in pH. It in fact forms a bit of hydroxide in solution. But it's less stable than carbonate and tens to slowly break down partly into carbonate over exposure to carbon dioxide. That will cause the pH to drift. I wanted a pH high enough to activate the ascorbic acid as a developing agent itself, and to make sure enough activity happened that thin emulsion films would work in the developer (I had trouble with this while attempting to use borax). The secondary concern for me was that my sodium carbonate is not very clean and seems to have some other cruft in it. My TSP is quite clean.

The pH of a solution of TSP is pretty high, between 12 and 14. I didn't want it _that_ high to try to prevent the ascorbic acid from totally dominating and to keep grain down. I also didn't want to see the pH drift much over time. The sulfite is enough in bath B to affect the pH but there is no buffer with just TSP and sulfite in there. I am no chemist, but the idea with the bicarbonate was to keep the initial pH from being as high as it might be from TSP and to form a buffer with the carbonate that will form from the TSP to prevent the drift from being noticeable. I don't know if that works, but so far the pH has been pretty stable.

TSP used to be common in developers, including some Edwal developers, and Diafine, but has fallen out of use.

That all being said, I think you could probably just replace the TSP with carbonate and some hydroxide and get the same results.

I am quite happy with the low amount of sulfite in B and the grain still being so nice. Delta 100 looks really nice in this developer in my opinion!