Two bath developers

CarlRadford · Nov 16, 2009

In Edge Of Darkness (2000) - page 94 - Thornton states that "I decided to reformulate the metol two bath for today's finer grain films" as such I understand that this covers Fuji Acros, Delta etc? I am particularly interested as I am just about to put some Acros 100 through it - as soon as the new stock arrives that is - and plan to use it for some night photography which could include some quite contrasty images. When were Acros and Delta introduced?

Alan Johnson · Nov 16, 2009

Info I have is that 100 Delta was added to Ilford's range in 1992 and Acros was announced in 2001.They may not have been available till later according to location.

CarlRadford · Nov 17, 2009

...

Alan Johnson said:
Info I have is that 100 Delta was added to Ilford's range in 1992 and Acros was announced in 2001.They may not have been available till later according to location.

One would assume it should do ok then. I will give it ago and report back!

davekarp · Nov 21, 2009

No problem using Thornton's two bath, DD76, divided Pyrocat, or Diafine with modern films like Delta 100, HP5+. FP4+, etc. I use a divided developer 100% of the time. Usually it is Thornton's, but I am preparing to experiment with Divided Pyrocat MC.

Keith Tapscott. · Nov 22, 2009

Ronald Moravec said:
I used to use a two back Leica or Stockler developer with Plus X and Tri x and it made beautiful sharp grain free negs . People who saw tri x prints did not believe they were Tri-x.

It does not work with modern thin emulsion films. Plus and Tri in current formation are thin. I have tried increasing the concentration of metol for the first bath and it helps, but frankly you are better off just using a standard D76. The new plus and Tri are better with d76 than I used to get with divided so I have totally switched.

Two-Bath`s are special purpose developers that were useful for processing B&W films when the subject matter was very high in contrast and the use of an ordinary developer would result in very dense highlights that would be difficult, if not impossible to print with satisfactory results. With normally lit subjects, prints often look lacklustre due to the flattening off in the highlights when a two-bath developer is used. Developers such Ultrafin, Rodinal, FX-39 and Perceptol when used well diluted provide very good control of contrast and compensation without making the highlights look too flat.

el wacho · Nov 22, 2009

i think (my memory is a little vague here) it was Mr Thornton in his book 'edge of darkness' that Stoeckler's two bath had a different purpose in mind - to aid the 35mm photographer in the development of frames shot in a variety of different lighting conditions. yes, highlights are controlled but also slightly underexposed frames are given better development without over developing the slightly overexposed frames. to confine them as special purpose developers is not necessary. prints may look lackluster because negs developed this way normally print well starting off as a grade 3 print, though i do concede that it is easy to get midtone separation with normal one shot development.

Donmck · Nov 22, 2009

Keith-
that's is the Problem-

Living in New England, more often than not,I wind up with low,normal,and high contrast scenes exposed on the same roll.The saying around here is---"if you don't like the weather,wait a few minutes,it'll change."

Using an old style(low contrast) two bath developer will take care of the high contrast negs but will make the low contrast negs
throwaways.

using a normal contrast developer for the A bath will give good contrast in the low/normal negs and still exhaust in the highlights in the high contrast negs--giving me a full printable roll.---or as Barry said---"automatic contrast control"

el wacho · Nov 23, 2009

for those who are interested in mr Thorton's experiences with two bath developers click here, go to "developers" in the menu, hover and then click "two bath". he addresses alot of what has been discussed here.

df cardwell · Nov 23, 2009

H. James Wolf said:
Over the past year, I've been trying various combinations of D-23 and Thorton's divided developers. Most seem to cut the film speed in half - shadows go blank - when compared with Xtol 1:3. Is this normal? Should I increase the time, agitation, or amount of metol? Is there a divided/two bath developer that gives full film speed?

James

Two things are happening.

First, two bath developers are probably not giving enough development to fully develop the shadows. While there is the old truism that we develop for the highlights, that is only true to a point. Without sufficient development, the low densities never build as far as they should.

Secondly, XTOL (and especially, 1+3) is the most efficient commercial developer for shadows. Even you went a little further, and extend your development time a bit, and reduced your agitation to 10 or 15 seconds every 3rd or 5th minute, you would literally PUSHING the shadows while PULLING the highlights, resulting in very full shadows, gentle highlights, and midtones that were exactly right.

D-23 (and D-76) are efficient shadow developers, yet with many films (Tri-X, TMY2, etc) Xtol is 1/2 to a full stop faster.

In short, you can improve your results with various 2-baths, but never approach what Xtol gives you naturally.

One of the reason folks go on about minimal agitation, not standing development, is that it lets you fully control, and balance, the shadows, midtones, and your highlights.

Two bath development was investigated in the 1930s to see if an shadows and highlights could be balanced, yet the researchers found little evidence of success. The technique proved useful for many types of work, and with some developers, yet the forgotten assumption to the work was treating agitation as a constant.

Allowing agitation to be a variable gives a careful worker that necessary degree of freedom to get the very most out of a negative, and for roll film shooters, to maximize the quality of the negatives or a roll shot under very different lighting conditions.

And THAT is what the two bath method has tried to do. Trust your evidence. You may lengthen the time in solution A, and get better results. Or, you can take the results from Xtol, and fine tune them.

g-luck

sanking · Nov 24, 2009

The mechanism of two bath development is such that shadow density can usually be increased with longer development time in Solution B, other factors remaining equal. In Solution B the negative develops first in the highlights, then the mid-tones, and finally the shadows. The developer exhausts quickly in the highlights so after a few minutes no farther development will take place here. Development continues in the mid-tones, with developer also gradually exhausting in these tonal areas. Development continues in the shadows until developer also exhausts here.

Increasing development time in Solution B from four to six minutes will most likely result in a significant increase in shadow density, with no negative impact on other tonal values.

Sandy King

df cardwell · Nov 24, 2009

And that's true too.... good stuff Sandy, thnx

Larry Bullis · Nov 25, 2009

It is also possible to cycle the two bath development. Go through the A then B sequence, then rinse, then apply the A then B sequence again, etc. Of course, there are limits because at some point you will begin to see increased fog.

I have done something like this even with E-6 in the first developer using the developer as supplied but with a carbonate bath as a "chaser". I don't recommend it, though, unless you really need ridiculous controls. The subject was the Olympic rain forest under unusual sunny conditions, sometimes with hour long pinhole exposures in which I needed to retain detail in very deep shadows.

dancqu · Nov 26, 2009

Multiple Passes

bowzart said:
It is also possible to cycle the two bath development.
Go through the A then B sequence, then rinse, then apply
the A then B sequence again, etc.

Multiple passes? I've suggested doing so several times.
Steve Anchell in an article in Camera and Darkroom also
suggests doing so. If the B bath is water the rinse may
be omitted. A water B needs an active A. Dan

sanking · Nov 26, 2009

bowzart said:
It is also possible to cycle the two bath development. Go through the A then B sequence, then rinse, then apply the A then B sequence again, etc. Of course, there are limits because at some point you will begin to see increased fog.

I understand that this would work, but how does one take advantage of the cycling in practice? Are you developing by inspection and evaluating the negative for density and contrast and then running it through another cycle if it is not there yet?

When developing roll film on reels the film generally goes through the fixer before I see the results, at which point it is obviously too late to run it through another cycle.

Sandy King

Larry Bullis · Nov 28, 2009

sanking said:
I understand that this would work, but how does one take advantage of the cycling in practice? Are you developing by inspection and evaluating the negative for density and contrast and then running it through another cycle if it is not there yet?

Sandy,

Yes, I desensitized the film and used an inspection light. This was in the E6 first developer, with a running tempered water bath doubling as a readily available rinse. Sheet film. Big test for the water heater.

I have used similar methods with roll film. As I'm sure you can imagine, control relies on a good deal of experience, and often won't provide much if any advantage. But think about an extreme situation, maybe an atomic bomb. I'd recommend Windisch pyrocatechin used as a multiply-cycled two bath.

I haven't used this with a bomb and hopefully never will, but I have used it in occasional extreme situations - mainly just to see if it would work. It does. It's hard to find enough need for this to develop a body of experience with it, so results are bound to be uncertain in particular situations. One could certainly do a great deal of testing and develop that experience, but would it be worth it?

gephoto · Nov 29, 2009

Dave,
Did you try the other 2 bath developers e.g. D-23, Anchell's or Stoeckler's before deciding on Thornton's 2 bath? I just curious what was the deciding factor for you. Thanks.
Grant

davekarp · Nov 29, 2009

I tried Diafine and Divided D-76 first. I decided to try the Thornton version because I wanted the extra acutance of the sodium metaborate B bath (as opposed to the Borax in DD-76) and the metol only formula (since I learned that Hydroquinone is inactive when D-76 is first mixed 76 anyway). I would still use DD-76 for 35mm film. Diafine also worked well, and lasts forever.

I want to try divided Pyrocat MC because I have had good experience with a staining developer in the past, and I am curious about using a 2 bath staining developer.

Philippe Grunchec · Dec 2, 2009

NO PRESOAK before two bath development: is that myth or reality (and why?)?

Larry Bullis · Dec 2, 2009

Because what is needed is to get the emulsion completely saturated with solution A. Presoak would dilute it, which is not helpful. The long agitation in A is to insure complete and even penetration, which is what presoaking is supposed to do, but without diluting.

sanking · Dec 2, 2009

bowzart said:
Because what is needed is to get the emulsion completely saturated with solution A. Presoak would dilute it, which is not helpful. The long agitation in A is to insure complete and even penetration, which is what presoaking is supposed to do, but without diluting.

Actually my opinion is that the idea that a presoak is a no-no with two bath development is something of a myth. A presoak with water will cause the gelatin emulsion to swell, which will allow rapid transfer of solutions in and out of the emulsion. The more it swells the more solution the emulsion will absorb. If you soak the film in Solution A long enough after the pre-soak the water will eventually be replaced by the reducer.

Test it both ways if there are any doubts. I think you will find that the results are quite similar in terms of contrast, and my impression is that the presoak does lead to more even development.

Sandy King

Larry Bullis · Dec 2, 2009

Does seem reasonable. The amount of water from the presoak couldn't make much difference.

Thomas Bertilsson · Dec 2, 2009

Could there be a risk of diluting Bath A in a developer such as Diafine by pre-soaking, where you use it over and over again for a long time?

I took for habit to never pre-soak, because I could see no benefit from it that was visible in my prints.

sanking · Dec 2, 2009

Thomas Bertilsson said:
Could there be a risk of diluting Bath A in a developer such as Diafine by pre-soaking, where you use it over and over again for a long time?

I took for habit to never pre-soak, because I could see no benefit from it that was visible in my prints.

I suppose that is possible. But I think you would have to run a lot of films through the solution before you would see any difference from water building up in Solution A.

Sandy King

el wacho · Dec 3, 2009

from memory and experience it is about 7ml per roll. i had Thornton's two bath ( the 35g sodium sulfite/L version ) for about 8 months in a 750 ml bottle and measured the difference in one session. i remember that the figure would vary with different films.

Philippe Grunchec · Dec 3, 2009

Thanks, Sandy, this was also my impression!
BTW, your Pyrocat (I use it now in glycol) is really great stuff! Which filter would you recommand for inspection? My N°3 DArk Green Kodak is really VERY dark!

Two bath developers

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