I use a custom modified Thornton 2 bath for pushing only, 2 stops or more. With this and my agitation technique, I'm able to print a full range of tones with films like Foma 100 @400 at grade 2 :) My customers at the lab are always pleasantly shocked at the controlled contrast and fine grain I give them when they send me pushed rolls
Great video ! I've been a fan of D-23 for like 30 years . I think I got my recipe from the book 'The Negative ' . Part of that series of books that came out long ago . About 15 years ago I needed to order some more metol and I was on ebay and found 2 , one pound jars of Kodak Elon (metol) from a shop that was going out of buisness . A lifetime supply for cheap ! It's true , no matter what film , always the same developing times ...... Hard to go wrong and for me , it looks really good .....If I need to push something , i'll just bump up the temp. a degree or two .......
In the late 1970s, I went through my "divided D-23" phase, which as you note is about the same except for its higher sulfite content. I quickly tired of having all of my negatives "homogenized" by its compensating effect, so moved on. Since the time in first bath is just to absorb developing agent into the emulsion with no development as such, and the time in the second bath is just to allow it to exhaust the absorbed developer, the noted timings differences based n film type seem irrelevant, as long as the film is in a bath long enough for its part of the process to be completed. Likewise, a program of timed agitation in the first bath seems pointless, once you've eliminated the chance of airbells from the initial pour-in. I really appreciate your focus on the technical side of the B&W photo chemical processes. which throws a lot of clarification into the huge numbers of videos on YT which maul the technology, passing urban legend and nonsense down from video to video.
I read about this in your book and having mulled over the dilemma of the zone system with roll film, I must admit this seems like a magic bullet, I will try this out. Another great video, thanks.
Thank you. I will try this one. Take a look at BTTB mod by Ruediger Hartung: He added 0,3g/l Phenidon and replaced the half of the metol with vitamin c.
What a wonderful video, thank you so much. I'm about to try my hand at a Karsh style portrait, all those lovely tones, this might be a good fit for that ? Once again thank you.
I am new to the dark room and only discovered your precious channel, thank you for sharing with us. A questgion came to mind after watching this video. Did Ansel Adams really swim in developer? :) Just kidding of course. So this 2 parts developer is doing wonders apparently, will have to try also this one. MY question..finally. If the negative goes through a certain type of developer, is there a relationship between negative dev. and print developer? Thanks again :)
Funny comment, thanks 😊 I personally don't match film dev to paper dev. With the film dev I want to make fully toned sharp negatives of good contrast. With the paper dev I want good blacks, nice contrast for my paper grades, and a reasonable speed - no more than 2 1/2 minutes for development. Hope that helps.
Hi John, Great video. I have some experience with D-23 two bath and have liked the results, but this this variant sounds even better. Since the development time is fixed, calibrating your film to the developer becomes superfluous, but the question of the correct ISO remains open. Could I just shoot a roll of film with different ISO's on each frame and choose the best exposure and use that as my proper film speed. Many thanks, Dan
It seems such a nice developer! Probably one of the best I've seen in terms of keeping that highlights where they should be. John, do you think that this is a appropiate developer for push processing for getting workable negatives? Thank you for your helpful videos.
Thanks for your comment. Some people have used this developer for pushing film but I don't think it's the best use of it or the best way to push film. Instead I use this for films with very varied contrast scenes and FX15, pyrocat, or a Diafine type developer for pushing. They are much better suited.
Good question, Robert. My metol is about three years old and going strong. I keep mine in a glass jar. Sodium sulphite should last years too and metaborate, if kept well sealed. It's all about keeping the oxygen and other gases away from them so good sealed jars and dark cupboard (light is energy and can speed up deterioration).
Hi John, Yet another question. I have done D-23 two bath, but I have used borax instead of the metaborate with no apparent ill effects. I do dispose the borax at the end of the day after processing 4 rolls of 120. Would that work with this protocol? Regards, Dan
It would. Thornton said he used metaborate because it lasts much longer. His formula allows the development of up to 15 films before needing the A and B replaced, considerably more than borax.
Hi, first let me say l don’t know what I’m talking about only what I’ve read hence the question ! In John Charles Woods book “ The zone system craft book” page 86 Kodak D23 he says the first bath sets the contrast and it’s the first bath which he suggests increased/ reduction in times for N-1 N-2 times and the second bath gets a constant 3 minutes. I note you suggest different times for different speed films and so was wondering does the length of time beyond 3 minutes for the second bath matter.
Hi John! Most 2-bath developers use an active developer as the A bath and you're spot on when you say longer in A will increase contrast of the finished negative. So what of B? This is a good question and one I've thought about a lot. The most important thing about B is that it utilises the remaining A to completion. So whatever time does this will do. I don't know what that time is but if it is three minutes then you're right, nothing much is happening after that time. However, as B has become a mix of A and B it too has become a very weak developer. This means that there is some continued action as the film sits in it. Probably not a lot but there must be some. That's maybe why Thornton specified his times the way he did (4 mins A, 4 mins B, then 5 mins A and 5 mins B etc). He was a thorough and detailed man and this is the only reason I can think for these times. Still, great food for thought and thanks for asking!
Hello! Great video as always. Can I substitute the sodium metaborate with borax + sodium sulphite in the same ratio as to D-23 Replenisher? I am not able to get it here. They don't send it out from UK. Cheers
You could use a borax bath B. Try 10g per litre water. It'll give finer grain and possibly less contrast so experiment with longer in bath A to try to up the contrast. Maybe 20%-30% longer in A. Another option would be sodium carbonate bath B. This might give slightly more grain and increased contrast. I've not tried either so can't give a definitive answer but these avenues are definitely worth exploring for you.
@@PictorialPlanet my apologies for coming back to you on the developer, but is it returned to the bottle and reused with out any additional time for up to 14 times?
No need to apologise, your questions are helpful for everyone, John. It is returned to the bottle and used normally for up to 15 times. Bath B must not contaminate bath A so care keeping the baths apart is required but not at all difficult. I place my used beaker of bath A to my left whilst keeping everything else to my right. There's no change in times as you develop more films through this two-bath. Please ask as many questions as you like or contact me through my website.
Thanks for this very interesting video, mr. Finch! I’ve been looking to get into mixing this developer from the Netherlands. In my search I found the RAW chemicals of Bellini. Is their dissolved Sodium Metaborate solution workable for this formula? Do I need to worry about oxidation of the liquid? Thanks for your time and help!
I think the best idea for you is to get all the chemicals you need, including solid metaborate, from Hamburg, an excellent photo chemical supplier called Fototechnik Suvatlar. See my website under suppliers. www.pictorialplanet.com/suppliers/suppliers.html
Hello John, another fantastic video, I'm going to try this very soon for sure. I've a question, how many rolls of 135/120 can I do with the stock solution? Is there a change of time when I reuse them? Thanks again for the great video :)
Hello John, first of all thank you for your channel and all the knowledge that you are sharing. For a darkroom newbie like me it's just priceless. I was thinking: is it a good idea to just get rid of 3/4 of part A after developing 15 rolls of film and then topping it up with fresh solution? Instead of just making it complately fresh again? Maybe the same with B part? Would BTTB benefit from that? Let me know what do you think. Best regards.
I see where you're coming from, wanting to keep some of the bromides, created by the development in A, for sharpness and reduced fog? However, as most of the work is done in B that would be the best place for some bromide. You could try an experiment, add a gram of potassium bromide to B and see if there's an improvement.
Have you ever measured your zone densities with the Thornton 2 bath? I may do my own test soon. I developed a couple rolls the other day in it and they didn’t have enough highlight punch. Developer was a few months old but got me thinking Of speed testing with a densitometer to try and really nail down my ei and possibly the activity in the 2nd bath to try and get as close to proper zone 1 and 8 densities.
I have never had a problem with poor highlights and have used this developer a lot, however, Thornton suggested using a B bath of 20g per litre metaborate to increase contrast if your negatives are always too flat. I have tested this and it does work. The other thing would be to extend the time in bath A. Bath A actually does develop the film so the longer the film is in A the higher you can push your highlights. This is how I found my 4 mins PAN F, 4.5 mins FP4, and 5 mins HP5.
Hello John. This is a great channel and I thoroughly enjoy your content and approach. I was motivated by your presentation of this developer to mix some up and give it a try on some rolls of HP5+ exposed in varying contrast situations. Overall I very much like the results, but for all 3 rolls (developed separately) I am getting pronounced streaking of over-development (lighter streaks) from the sprocket holes - most noticeably where there are highlights, such as expansive sky. I followed your agitation scheme for both baths and developed for 4, 4:30 and 5 minutes in both baths for the three rolls. Any thoughts on the cause of the streaking or how to prevent? How critical is the timing of pouring in Bath B after Bath A has been poured out? Thanks!
Hi Jeff. The Thornton two bath is a good developer and doesn't seem to often give problems. Streaks from sprocket holes usually means too vigorous agitation. Did you do inversion agitation or twizzle stick? The developer does use metol which is prone to bromide drag but this is also rare with this developer. If it is bromide drag it'll be obvious under other parts of the image, not just the sprockets. To answer your other question, Bath B should be poured in immediately after bath A is poured out.
Hello John, I used inversions in a Paterson tank and probably erred on the side of too little for bath B. The streaking is not my experience with bromide drag as it seems to only appear in highlight areas and not the full frame as you also suggested. It is also not apparent on every negative as I cannot discern any streaking in adjacent negatives with significantly less density and more lower zone detail. I will try your twizzle stick scheme and see if there is a difference.
Dear John, i'm using BTTB for some time now. Last time i developed with it 2 rolls of 35mm film at the same time - 1x ilford pan 400 and 1x rollei retro 400s. 21C A 4,5min + B 4,5min. I was quite surprised with the results of rollei retro. The negative was very thin when compared to ilford (and also my previous results with Agfa Aviphot). I wonder what might have happened. Rolls and chemichals were fresh. I rated films at box speed. I read somwhere that Rollei retro with BTTB is actually 200 iso film - is maybe that the case?
Hello John! Thanks for creating this channel, one of the best and informative sources for film development. I would like to make some of this 2 part developper but can only find Sodium Metaborate in liquid form (the Bellini Sodium Metaborate Octahydrate Solution 280 g/l). Could you tell me how much I should use instead of the 2.5 tbsp of solid Sodium Metaborate? Thank you!! Ian
@@PictorialPlanet Thank you. Yes I had seen that website linked from yours. Living in the EU I would have prefered to buy here but I may go for that one then. Thanks again... I ordered your book and am very much looking forward to learning from it :)
You can replace sodium metaborate in the formula with sodium hydroxide and borax. In solution, the two make sodium metaborate reversibly, giving a buffering effect. 1.5g sodium hydroxide plus 7g borax generates 10g sodium metaborate. In Bath 2 of BT2B, I use 1.8g NaOH plus 8.4g borax in 1 litre of solution.
Absolutely! It's close enough to bath A metol=2tsp - sod. sulphite=3Tbl + 1.5tsp - 1Ltr water (add a pinch of sulphite to the water before dissolving metol then rest of sulphite). Bath B sod. metaborate=2.5tsp to 1Ltr water. Hope that helps. I'll put this in the video notes.
Have TRIED that BT 2-Bath -- never really liked it -- by the way -- I have the SAME TIMER as you given to me from the Dreaded Sister-in-Law but I'm not sure how accurate it is -- done a few 'tests ' with my SMITHS with the Alarm -- that one is GERMAN -- have you ever 'Got Into It' to lubricate -- I can't see HOW to take off the back -- no SCREWS I can see -- Peter
How would you use this if you push/pull a film? Is the compensation sufficient to just develop with the same times? Seems almost magical if so. It would allow you to use a film like HP5+ and shoot at multiple ISO’s on the same roll essentially!
This developer is not meant for pushing or pulling film. You should still be exposing correctly. But the developer does help keep the photographs within the tonal range of the film.
Hi B! This question is often asked about two bath developers. If a frame has been over exposed in the highlights then the developer quickly stops developing those highlights while continuing to develop the shadows thus compensating for the excessive contrast. If the frame is underexposed then the negative continues to develop, with little or no compensation thus increasing contrast to near normal. Basically, the developer is treating each negative somewhat individually.
@@PictorialPlanet Thank you so much for this thoughtful answer! May I ask you another question, I've been looking for answers on the web. Basically, I'm turning into landscape photography and my main goal is to print my photographs on VC paper. I can't seem to decide which developer to go for, highlight protection is important for my work. Do I go with a two-bath solution to get a balanced negative? Do I go with a Pyro solution? Or do I go with dilute (1+3) ID11 which I'm used to? Thanks.
B, your question is a very good one, quite profound in fact. It's a question I think many are, sooner or later, confronted with. Do I use a new developer that might improve or benefit my photography or do I stay with one I know, one I've used a lot. I have no doubt of the correct choice. Stay with what you know, especially if it's an already good choice. Your choice of ID11/D76 is a very good one! As Stock it's bold, punchy, and works well with the zone system. 1+1 is a lovely compromise in contrast and sharpness. And 1+3 takes good care of the highlights and provides extra sharpness also. It's such a great all round developer that's very hard to beat, even with modern pyro formulas. If you made your own developers I'd say use Crawley's FX15 which acts like ID11 "done right "and uses all the same dilutions but if you don't make your own then I'd say stick with ID11/D76 and make beautiful photographs - the photograph is after all by the photographer not by the developer my friend. Thanks for asking such a good question.
Not a good use of a two bath. If you are wanting to push film then ID68 is a better developer. Pushing a film is under exposing it and so one needs a developer that will work hard to raise the lower zones. Oh, Crawley's FX15 or FX11 would work well.
@@PictorialPlanet Hello John. Thank you for the reply. It was usually lack of 'punch' in the prints unless it was a photograph taken on a bright day. I watched the German video about the 'modified Thornton 2 Bath'. I was surprised to see that he develops his negatives twice! I thought that when the 1st development cycle was completed there would not be any silver left to re-develop. I am only a keen amateur and may well be incorrect.
Here's an idea to get more punch. BT 2-bath is really a D23 type developer followed by an alkaline accelerator. Therefore the first bath does actually develop the film. This means one can increase the contrast of the negative by developing for a longer time in bath A. That might give you the punch you want. To start try 50% longer in A but the original time in B.
It's usually pretty normal up to 24C, never tried it higher. Can you keep it down to 24? One advantage Thornton's 2 bath has is the constituents. They're similar to D23 which is a good tropical developer so you shouldn't have issues with fog but should use a hardening stop or fix. See my book page 303
@@PictorialPlanet Thank you for such a promt response! Sure, I can keep it even down to 20C but it takes time. It's not very convenient for developing single rolls. Have I understood correctly that at 24C no compensation of time is needed, right? Unfortunately, I didn't buy your book when it was possible. Now it's become impossible for people from my country (Russia) :)
With the first bath, where development is happening, just like D23, I use Kodak's agitation -first 30 seconds constant, then 5 seconds each 30. In bath B I agitate for 5 seconds and then 5 seconds each minute (to stop bromide drag).
I use a custom modified Thornton 2 bath for pushing only, 2 stops or more.
With this and my agitation technique, I'm able to print a full range of tones with films like Foma 100 @400 at grade 2 :)
My customers at the lab are always pleasantly shocked at the controlled contrast and fine grain I give them when they send me pushed rolls
@@flutgraben13 thanks for the modification :)
Could you tell what the modification you are talking about?
Can you share the modification?
Great video ! I've been a fan of D-23 for like 30 years . I think I got my recipe from the book 'The Negative ' . Part of that series of books that came out long ago . About 15 years ago I needed to order some more metol and I was on ebay and found 2 , one pound jars of Kodak Elon (metol) from a shop that was going out of buisness . A lifetime supply for cheap !
It's true , no matter what film , always the same developing times ...... Hard to go wrong and for me , it looks really good .....If I need to push something , i'll just bump up the temp. a degree or two .......
Thanks for your comment Jon. I agree, great developer.
Clive Eggington gave me this recipe years ago. It's really easy to use. First time I've seen someone else use it 👍
Yes, excellent 2-bath for modern films.
In the late 1970s, I went through my "divided D-23" phase, which as you note is about the same except for its higher sulfite content. I quickly tired of having all of my negatives "homogenized" by its compensating effect, so moved on. Since the time in first bath is just to absorb developing agent into the emulsion with no development as such, and the time in the second bath is just to allow it to exhaust the absorbed developer, the noted timings differences based n film type seem irrelevant, as long as the film is in a bath long enough for its part of the process to be completed. Likewise, a program of timed agitation in the first bath seems pointless, once you've eliminated the chance of airbells from the initial pour-in. I really appreciate your focus on the technical side of the B&W photo chemical processes. which throws a lot of clarification into the huge numbers of videos on YT which maul the technology, passing urban legend and nonsense down from video to video.
Thanks, Randall! I appreciate your experience with this.
Great video, John. Very interesting. For 35mm/roll film users, it makes you think why bother with any other developer!
Agreed!
I read about this in your book and having mulled over the dilemma of the zone system with roll film, I must admit this seems like a magic bullet, I will try this out. Another great video, thanks.
You'll love it!
Cada vídeo, oro puro. Información muy valiosa.
Thank you. I will try this one. Take a look at BTTB mod by Ruediger Hartung: He added 0,3g/l Phenidon and replaced the half of the metol with vitamin c.
Looking now!
does anyone know if the suffix "sicc" is the same as "anhydr"?
Important question from occasional shooter: what is expected shelf life of this developer?
About 4-6 months in closed bottles
What a wonderful video, thank you so much. I'm about to try my hand at a Karsh style portrait, all those lovely tones, this might be a good fit for that ? Once again thank you.
Thanks for your comment, John.
I am new to the dark room and only discovered your precious channel, thank you for sharing with us. A questgion came to mind after watching this video. Did Ansel Adams really swim in developer? :) Just kidding of course. So this 2 parts developer is doing wonders apparently, will have to try also this one. MY question..finally. If the negative goes through a certain type of developer, is there a relationship between negative dev. and print developer? Thanks again :)
Funny comment, thanks 😊 I personally don't match film dev to paper dev. With the film dev I want to make fully toned sharp negatives of good contrast. With the paper dev I want good blacks, nice contrast for my paper grades, and a reasonable speed - no more than 2 1/2 minutes for development. Hope that helps.
@@PictorialPlanet it does, thanks 👍🏻
Great video as usuel John, were do you get your chemicals from,
Hi Martin, thanks for your great channel ! I have a suppliers list on my website.
www.pictorialplanet.com/suppliers/suppliers.html
Hi John, Great video. I have some experience with D-23 two bath and have liked the results, but this this variant sounds even better. Since the development time is fixed, calibrating your film to the developer becomes superfluous, but the question of the correct ISO remains open. Could I just shoot a roll of film with different ISO's on each frame and choose the best exposure and use that as my proper film speed. Many thanks, Dan
See my video series on the EZ Zone system. I talk about that sort of thing. Just ignore the development time part.
It seems such a nice developer! Probably one of the best I've seen in terms of keeping that highlights where they should be. John, do you think that this is a appropiate developer for push processing for getting workable negatives? Thank you for your helpful videos.
Thanks for your comment. Some people have used this developer for pushing film but I don't think it's the best use of it or the best way to push film. Instead I use this for films with very varied contrast scenes and FX15, pyrocat, or a Diafine type developer for pushing. They are much better suited.
John what would be the shelf life of the raw chemicals for this developer thanks?
Good question, Robert. My metol is about three years old and going strong. I keep mine in a glass jar. Sodium sulphite should last years too and metaborate, if kept well sealed. It's all about keeping the oxygen and other gases away from them so good sealed jars and dark cupboard (light is energy and can speed up deterioration).
@@PictorialPlanet Thank you John
Hi John, Yet another question. I have done D-23 two bath, but I have used borax instead of the metaborate with no apparent ill effects. I do dispose the borax at the end of the day after processing 4 rolls of 120. Would that work with this protocol? Regards, Dan
It would. Thornton said he used metaborate because it lasts much longer. His formula allows the development of up to 15 films before needing the A and B replaced, considerably more than borax.
Hi, first let me say l don’t know what I’m talking about only what I’ve read hence the question ! In John Charles Woods book “ The zone system craft book” page 86 Kodak D23 he says the first bath sets the contrast and it’s the first bath which he suggests increased/ reduction in times for N-1 N-2 times and the second bath gets a constant 3 minutes. I note you suggest different times for different speed films and so was wondering does the length of time beyond 3 minutes for the second bath matter.
Hi John! Most 2-bath developers use an active developer as the A bath and you're spot on when you say longer in A will increase contrast of the finished negative. So what of B? This is a good question and one I've thought about a lot. The most important thing about B is that it utilises the remaining A to completion. So whatever time does this will do. I don't know what that time is but if it is three minutes then you're right, nothing much is happening after that time. However, as B has become a mix of A and B it too has become a very weak developer. This means that there is some continued action as the film sits in it. Probably not a lot but there must be some. That's maybe why Thornton specified his times the way he did (4 mins A, 4 mins B, then 5 mins A and 5 mins B etc). He was a thorough and detailed man and this is the only reason I can think for these times. Still, great food for thought and thanks for asking!
Hello! Great video as always. Can I substitute the sodium metaborate with borax + sodium sulphite in the same ratio as to D-23 Replenisher? I am not able to get it here. They don't send it out from UK. Cheers
You could use a borax bath B. Try 10g per litre water. It'll give finer grain and possibly less contrast so experiment with longer in bath A to try to up the contrast. Maybe 20%-30% longer in A. Another option would be sodium carbonate bath B. This might give slightly more grain and increased contrast. I've not tried either so can't give a definitive answer but these avenues are definitely worth exploring for you.
@@PictorialPlanet Ok I'll try borax bath B. I trade always kontast for sharpness :-) Thank you very much for your answer. Your book is very good
Hi, are you able to give a shelf life of the Barry Thornton developer? I find your videos very good, thank you 🙏
Hi John! At leased six months. Best if kept in PET plastic or glass with a tiny squirt of lighter gas in the top.
@@PictorialPlanet my apologies for coming back to you on the developer, but is it returned to the bottle and reused with out any additional time for up to 14 times?
No need to apologise, your questions are helpful for everyone, John. It is returned to the bottle and used normally for up to 15 times. Bath B must not contaminate bath A so care keeping the baths apart is required but not at all difficult. I place my used beaker of bath A to my left whilst keeping everything else to my right. There's no change in times as you develop more films through this two-bath. Please ask as many questions as you like or contact me through my website.
Thanks for this very interesting video, mr. Finch! I’ve been looking to get into mixing this developer from the Netherlands. In my search I found the RAW chemicals of Bellini. Is their dissolved Sodium Metaborate solution workable for this formula? Do I need to worry about oxidation of the liquid? Thanks for your time and help!
I think the best idea for you is to get all the chemicals you need, including solid metaborate, from Hamburg, an excellent photo chemical supplier called Fototechnik Suvatlar. See my website under suppliers.
www.pictorialplanet.com/suppliers/suppliers.html
@@PictorialPlanet thanks so much for the ultra quick reply and the tip. I'm going to contact them and start experimenting!
Thank you Mr Finch. Your work is great. Keep it up. I'm fan.
Hello John, another fantastic video, I'm going to try this very soon for sure. I've a question, how many rolls of 135/120 can I do with the stock solution? Is there a change of time when I reuse them? Thanks again for the great video :)
Barry said you can process up to 15 films through this 2 bath. Then make a fresh A and B.
Hello John, first of all thank you for your channel and all the knowledge that you are sharing. For a darkroom newbie like me it's just priceless. I was thinking: is it a good idea to just get rid of 3/4 of part A after developing 15 rolls of film and then topping it up with fresh solution? Instead of just making it complately fresh again? Maybe the same with B part? Would BTTB benefit from that? Let me know what do you think. Best regards.
I see where you're coming from, wanting to keep some of the bromides, created by the development in A, for sharpness and reduced fog? However, as most of the work is done in B that would be the best place for some bromide. You could try an experiment, add a gram of potassium bromide to B and see if there's an improvement.
Have you ever measured your zone densities with the Thornton 2 bath? I may do my own test soon. I developed a couple rolls the other day in it and they didn’t have enough highlight punch. Developer was a few months old but got me thinking Of speed testing with a densitometer to try and really nail down my ei and possibly the activity in the 2nd bath to try and get as close to proper zone 1 and 8 densities.
I have never had a problem with poor highlights and have used this developer a lot, however, Thornton suggested using a B bath of 20g per litre metaborate to increase contrast if your negatives are always too flat. I have tested this and it does work. The other thing would be to extend the time in bath A. Bath A actually does develop the film so the longer the film is in A the higher you can push your highlights. This is how I found my 4 mins PAN F, 4.5 mins FP4, and 5 mins HP5.
Hello John. This is a great channel and I thoroughly enjoy your content and approach. I was motivated by your presentation of this developer to mix some up and give it a try on some rolls of HP5+ exposed in varying contrast situations. Overall I very much like the results, but for all 3 rolls (developed separately) I am getting pronounced streaking of over-development (lighter streaks) from the sprocket holes - most noticeably where there are highlights, such as expansive sky. I followed your agitation scheme for both baths and developed for 4, 4:30 and 5 minutes in both baths for the three rolls. Any thoughts on the cause of the streaking or how to prevent? How critical is the timing of pouring in Bath B after Bath A has been poured out? Thanks!
Hi Jeff. The Thornton two bath is a good developer and doesn't seem to often give problems. Streaks from sprocket holes usually means too vigorous agitation. Did you do inversion agitation or twizzle stick? The developer does use metol which is prone to bromide drag but this is also rare with this developer. If it is bromide drag it'll be obvious under other parts of the image, not just the sprockets.
To answer your other question, Bath B should be poured in immediately after bath A is poured out.
Hello John, I used inversions in a Paterson tank and probably erred on the side of too little for bath B. The streaking is not my experience with bromide drag as it seems to only appear in highlight areas and not the full frame as you also suggested. It is also not apparent on every negative as I cannot discern any streaking in adjacent negatives with significantly less density and more lower zone detail. I will try your twizzle stick scheme and see if there is a difference.
Good idea to try the twizzle stick.
Dear John, i'm using BTTB for some time now. Last time i developed with it 2 rolls of 35mm film at the same time - 1x ilford pan 400 and 1x rollei retro 400s. 21C A 4,5min + B 4,5min. I was quite surprised with the results of rollei retro. The negative was very thin when compared to ilford (and also my previous results with Agfa Aviphot). I wonder what might have happened. Rolls and chemichals were fresh. I rated films at box speed. I read somwhere that Rollei retro with BTTB is actually 200 iso film - is maybe that the case?
Mmmmm, does sound like it's an odd film. I only use Ilford so I can't help much here.
Hello John! Thanks for creating this channel, one of the best and informative sources for film development. I would like to make some of this 2 part developper but can only find Sodium Metaborate in liquid form (the Bellini Sodium Metaborate Octahydrate Solution 280 g/l). Could you tell me how much I should use instead of the 2.5 tbsp of solid Sodium Metaborate? Thank you!! Ian
If you're quick you'll get it here www.stillphotographic.com/shop
@@PictorialPlanet Thank you. Yes I had seen that website linked from yours. Living in the EU I would have prefered to buy here but I may go for that one then. Thanks again... I ordered your book and am very much looking forward to learning from it :)
Great, I think it's your best option. If you do go with the Bellini 280g/ltr then you'll need 43ml of that made up to 1 litre with water.
You can replace sodium metaborate in the formula with sodium hydroxide and borax. In solution, the two make sodium metaborate reversibly, giving a buffering effect. 1.5g sodium hydroxide plus 7g borax generates 10g sodium metaborate. In Bath 2 of BT2B, I use 1.8g NaOH plus 8.4g borax in 1 litre of solution.
Great video John! I'd love to try this developer but don't have a scale. Is there any way you could post a Tbs/tsp version of the recipe?
Absolutely! It's close enough to bath A metol=2tsp - sod. sulphite=3Tbl + 1.5tsp - 1Ltr water (add a pinch of sulphite to the water before dissolving metol then rest of sulphite). Bath B sod. metaborate=2.5tsp to 1Ltr water. Hope that helps. I'll put this in the video notes.
@@PictorialPlanet Thanks so much for this John! I appreciate you going the extra mile.
Hi is Sodium Metaborate also known as Borax? Having trouble finding Metaborate. Thanks
Hi John, no metaborate is a different alkali. I have a suppliers list on my website that might help if you're in U.K./ Europe?
No, see my reply to an earlier comment above.
Have TRIED that BT 2-Bath -- never really liked it -- by the way -- I have the SAME TIMER as you given to me from the Dreaded Sister-in-Law but I'm not sure how accurate it is -- done a few 'tests ' with my SMITHS with the Alarm -- that one is GERMAN -- have you ever 'Got Into It' to lubricate -- I can't see HOW to take off the back -- no SCREWS I can see -- Peter
Ha! I've never been into it but it does squeak a lot. I should have a look 👀
John, this was my first introduction to two bath developers. Could you please explain what is in the Bath “B”? Thanls
Bath b contains an alkaline accelerator. In this case sodium metaborate.
@@PictorialPlanet how much?
12g in 1Ltr water
@@PictorialPlanet thanks so much! I just looked up the article on Goggle too. I am enjoying your channel.
Hi, thanks for the video. Can I ask what temperature the water needs to be when making / mixing up the 2 baths? Thanks.
I usually mix all my developers at around 50C so this is good for bath A and bath B. Of course when developing film I use 20C
@@PictorialPlanet thank you for the reply. I’m going to make some in the next week or so. I’ll tag you on Instagram with some results.
Hi there, would like to try this... where are you getting your chemicals in the UK please?
Check out my website pictorialplanet.com. I have a suppliers list.
How would you use this if you push/pull a film? Is the compensation sufficient to just develop with the same times? Seems almost magical if so. It would allow you to use a film like HP5+ and shoot at multiple ISO’s on the same roll essentially!
This developer is not meant for pushing or pulling film. You should still be exposing correctly. But the developer does help keep the photographs within the tonal range of the film.
Good day. is it possible to replace the methol with phenidone?
Try it! Use about 1/10th the amount of metol. Let us know how it works.
@@PictorialPlanet thanks, I will try.
How is it developing each frame individually?
Hi B! This question is often asked about two bath developers. If a frame has been over exposed in the highlights then the developer quickly stops developing those highlights while continuing to develop the shadows thus compensating for the excessive contrast. If the frame is underexposed then the negative continues to develop, with little or no compensation thus increasing contrast to near normal. Basically, the developer is treating each negative somewhat individually.
@@PictorialPlanet Thank you so much for this thoughtful answer! May I ask you another question, I've been looking for answers on the web.
Basically, I'm turning into landscape photography and my main goal is to print my photographs on VC paper. I can't seem to decide which developer to go for, highlight protection is important for my work.
Do I go with a two-bath solution to get a balanced negative? Do I go with a Pyro solution? Or do I go with dilute (1+3) ID11 which I'm used to?
Thanks.
B, your question is a very good one, quite profound in fact. It's a question I think many are, sooner or later, confronted with. Do I use a new developer that might improve or benefit my photography or do I stay with one I know, one I've used a lot. I have no doubt of the correct choice. Stay with what you know, especially if it's an already good choice. Your choice of ID11/D76 is a very good one! As Stock it's bold, punchy, and works well with the zone system. 1+1 is a lovely compromise in contrast and sharpness. And 1+3 takes good care of the highlights and provides extra sharpness also. It's such a great all round developer that's very hard to beat, even with modern pyro formulas. If you made your own developers I'd say use Crawley's FX15 which acts like ID11 "done right "and uses all the same dilutions but if you don't make your own then I'd say stick with ID11/D76 and make beautiful photographs - the photograph is after all by the photographer not by the developer my friend. Thanks for asking such a good question.
When you say that it "develops each frame individually" Can you use this to push film 1+ stops on the same roll as normally exposed film?
Not a good use of a two bath. If you are wanting to push film then ID68 is a better developer. Pushing a film is under exposing it and so one needs a developer that will work hard to raise the lower zones. Oh, Crawley's FX15 or FX11 would work well.
Hello John. I have had mixed success with the Thornton 2 bath developer. Have you tried Pyrocat HD as a 2 bath developer? I use the Glycol version.
Hi Dennis. No, I haven't tried 2-bath with pyrocat but it should work. But what's been your problems with BT 2-bath?
@@PictorialPlanet Hello John. Thank you for the reply. It was usually lack of 'punch' in the prints unless it was a photograph taken on a bright day. I watched the German video about the 'modified Thornton 2 Bath'. I was surprised to see that he develops his negatives twice! I thought that when the 1st development cycle was completed there would not be any silver left to re-develop. I am only a keen amateur and may well be incorrect.
Here's an idea to get more punch. BT 2-bath is really a D23 type developer followed by an alkaline accelerator. Therefore the first bath does actually develop the film. This means one can increase the contrast of the negative by developing for a longer time in bath A. That might give you the punch you want. To start try 50% longer in A but the original time in B.
@@PictorialPlanet Thank you John. I'll give it a try.
Would this 2-bath be beneficial with a pushed film.
This is not something I've used this developer for unfortunately.
Hello John,
Is there a temperature compensation chart for 2BBT developer? My usual temperature at home is about 26C.
It's usually pretty normal up to 24C, never tried it higher. Can you keep it down to 24? One advantage Thornton's 2 bath has is the constituents. They're similar to D23 which is a good tropical developer so you shouldn't have issues with fog but should use a hardening stop or fix. See my book page 303
@@PictorialPlanet Thank you for such a promt response!
Sure, I can keep it even down to 20C but it takes time. It's not very convenient for developing single rolls.
Have I understood correctly that at 24C no compensation of time is needed, right?
Unfortunately, I didn't buy your book when it was possible. Now it's become impossible for people from my country (Russia) :)
You should be ok. I'd try it first but it might need a minute knocked off but it's worth trying without. Let us know how you get on.
What agitation method do you use with this developer?
With the first bath, where development is happening, just like D23, I use Kodak's agitation -first 30 seconds constant, then 5 seconds each 30. In bath B I agitate for 5 seconds and then 5 seconds each minute (to stop bromide drag).
Is this Exactol lux?
No Jo, the is Barry Thornton's metol two bath.
Thank you. Have you worked with the Exactol Lux?
@noc838 I love Exactol Lux!
@@PictorialPlanet could you please do a video about it?
@noc838 thanks for the request but I only do videos about developers anyone can make at home.