View Full Version : 2 bath and 8x10

20-Sep-2006, 02:52
2 bath developer with 8x10 hp5 and jobo 3005 with constant agitation, would this be a good choice, if so could anyone give suggested times.
Thanks Terry

Donald Qualls
20-Sep-2006, 10:44
Most two-bath developers work best with little agitation in the second bath, to avoid the possibility of prematurely washing the developing agent out of the emulsion. OTOH, I don't know how hard to have to agitate to actually precipitate that disaster. In any case, development is pretty nearly independent of agitation with 2-bath, because the times are driven by diffusion rates and exhaustion; I'd suggest starting with the same times that would be used in small tanks, and adjust after seeing the first negative if needed.

20-Sep-2006, 10:58
Donald is correct as I understand two-bath developers - over-agitation can wash out the Bath A causing severe underdevelopment. What results are you looking for?

- Randy

David Karp
20-Sep-2006, 13:19
This is mostly copied from an old post I made:

I have used Diafine, DD-76, and the late Barry Thornton's 2 bath formula, which is a derivation of the Stoeckler formula and DD-23. I have also used X-Tol 1:3, PMK, and dilute D-76/ID-11. I have now pretty much standardized on Thornton's 2-Bath.

First, Thornton's formula: A bath - 750 ml water, 6.5g metol, 80g sodium sulfite, water to make 1L. B bath - 750 ml water, 12g sodium metaborate for N development, water to make 1L (7g/liter for N-, and 20g/liter for N+). In spite of the formula, I have split the sodium sulfite 50/50 between the two baths with good success. 5 minutes in each bath without a wash in between works well. Extra time or temperature variations make little difference, especially if you split the sodium sulfite between the two baths. I have used this formula with 4x5 HP5+, FP4+, and Delta 100. I have not tried it with T-Max films. I expose HP5+ at 200, and FP4+ at 64-80, and Delta 100 at 50.

A little background on how Thornton put this formula together, from his book "The Edge of Darkness," and my recollection of his now defunct website. He had been using the Stoeckler 2 bath formula, but decided that it needed a reformulation for modern films. He liked the idea of a metol only developer because he wanted to take advantage of metol’s ability to deliver high acutance, especially when it is carried over into bath 2, where, mixed with the accelerator "it gives the effect of dilute development for edge effects." He felt that the Stoeckler formula needed more metol in bath A, and concluded that the Ansel Adams version of DD-23 included too much metol. He also cut the amount of sodium sulfite from 100g/L to 80g/L to “cut down grain dissolving activity and increase apparent sharpness without increasing grain size too much.” Thornton felt that modern film emulsions were too thin to use borax as the accelerator, so he used sodium metaborate instead. After a while, Thornton became interested in PMK, and started experimenting with it. He found that he did not like it, and invented his Dixactol, which used pyrocatechol.

I find that his 2 bath formula works great for the landscapes and exterior architecture I like to photograph. It also gives the opportunity to accomplish "+" or "-" development by varying the amount of sodium metaborate in the B bath, as mentioned above. I have not needed to do minus development because of the compensating nature of the two bath system. I like his formula better than DD-76 and Diafine. It is far easier to use than other developers. There is really very little concern over time and temperature, and you can develop different types of film in the soup at the same time. I have found that I get good highlights, and if I meter properly, good detail in the shadows in scenes with a broad range from highlight to shadow. In a few instances where I felt I needed more contrast, instead of developing my backup neg in the “+” B Bath, I gave the first negative a bath in selenium toner diluted 1:1 for 5 minutes. This gives approximately the equivalent of N+1 development without an increase in grain. Developing negatives this way is easy. No anxiety regarding time or temperature. Almost one half the amount of time in the developer compared to X-Tol 1:3. Plus, I really like the way the negatives look and how they print, which is the most important thing of all.

If I had an 8x10 I would use this formula without question.

David Karp
20-Sep-2006, 13:21
By the way, if I remember correctly, Anchell and Troop say that constant agitation is not a problem with 2 baths.

Personally, I agitate for 15 seconds every minute in both baths using a Slosher.

22-Sep-2006, 13:17

I have over the last six months been trying to create the perfect two-bath developer for my needs. I still haven't quite got the 'perfect one' after numerous incarnations and formulations, but am a lot nearer. Time, and to a certain extent enthusiasm, has prevented me from continuing my research but...

In the process of messing around with two-bath's I have found that the key to agitation is how little of it you give, but not necessarily in the way you'd think. Too little agitation and you get flat neg's and flat prints (in both baths, and especially in the second). No agitation is even worse. Moderate agitation all the way to constant agitation will give you perfect neg's. You don't have to worry about losing any shadow detail or having burnt highlights with constant agitation, and here's why that may be: In the first bath developer is absorbed by the emulsion and the backing and it will be a very small amount. In the second bath, consisting of an accelerator only - alkaline to a varying degree - the developer does what it should, develops to exhaustion. No further agitation will effect this because you are only swirling an alkaline solution about - you are not feeding the highlights with any more fresh developer. Transferance of developer from adjacent areas in the neg. will be miniscule due to the amounts absorbed and the fact that the accelerator will be working on that too, constantly reducing it.

There has been a lot of confusion over this issue in the past. My own experiments have shown that constant agitation is perfectly usable with two bath developers. They are a great tool for producing truely great photo's that print easily with masses of detail (thanks to the surface acting developers in low concentration). Give it a go. You may find that you get low contrast neg's. If so use a stronger alkali - S. metaborate or S. carbonate (if carbonate don't use a stop bath, only a water rinse or two to avoid any CO2 bubbles damaging the neg) - 20 to 30g per litre. You can then tailor the results to get the negative just the way you like them.

As for times, 5 minutes in both baths. The second bath only adds density and beyond five minutes you might end up having a really meaty negative (the alkaline will change the contrast remember).

Best of luck. I hope this made sense. Take care, have fun Neilski.

23-Sep-2006, 00:00
Hi everyone thanks for all the useful comments.

5-Oct-2006, 02:45
I'm also going to start experimenting with 2 baths (4x5 only sorry), and I have a few questions.
+ Do you reuse the baths ? I've read conflicting information in this; so I was wondering if it would be better to try to make a concentrate for bath A and use it as one shot, or just make the 1 liter bottle and reuse it several times... From my reading the B bath is easily reusable...
+ Also, some other conflicting reading tells me that a water stop; or a water rince before stop is good because it brings the Ph slower to neutral... Does anyone have an opinion on this ?
+ What about a water pre-soak ? I tend to do this for 4x5 to clear the anti-halation dyes, but I wonder how it will impact the "bath A", surely it will make it less efficient ?

Sorry for the newbie question :D

David Karp
5-Oct-2006, 13:14
As for the pre-soak, don't do it. You want the emulsion to soak up a "full load" of the bath A with the developing agent. Soaking first will effectively dilute your A bath.

All 2 baths I have tried are reuseable. For example, Barry Thornton's recommendation for his 2-bath was 15 films (equivalents of 8x10 sheets) per bath. Diafine seems to go on forever. I used to throw it away because its look scared me even though the negatives developed in that old soup looked fine.

Regarding stop baths, I have done it both ways. I have used an indicator stop bath and I have used water. I now use water. It seems to work fine, so I just eliminated another chemical. I only use stop bath with prints now. Just don't stop between A and B, thats the only limitation of which I am aware.

6-Oct-2006, 13:49
Thank you David; I did mix 1L of Bath A and 500ml of bath B without problems.
I will continue using my stop bath and will not presoak... I'm sure the dev will certainly /look/ scary after 15 films dye are dissolved in it :D

Jim Noel
11-Oct-2006, 13:02
If developmentis carried to completion in a 2 bath developer, the second bath will totally use up the first bath which was absorbed by the film so that a water rinse is all that is needed prior to fixing.