To Diafine or not to Diafine

I have a friend, a fellow APUGer who is a big advocate of Diafine. I shoot large format mainly, with FP4 rated at EI 64, and I am a basic zone system guy, so I am not sure if it is for me. I have read that it is a very good developer for small formats, particularly if you want to shoot at higher than box speed, sometimes much higher, but not if you want more consistent and predictable contrast control.

This came up because I am trying to photograph a scene in my neighbourhood that is going to disappear soon. The light has not been co-operating, with lots of clouds, both thick and thin, changing the light literally every minute. The ideal moment to click the shutter seems to be when the sun breaks through for a moment and the wind dies down, but that makes for a ten or eleven stop range. That would not be a problem in an of itself if I had tested for N minus development to that degree, but I have not yet. It is still no big deal. I can shoot and guesstimate how much to reduce development (although I hate bracketing with 8x10!). Or is Diafine the magic bullet that is going to save the day?

If you use the Zone System you must also use a conventional developer. Diafine provides no means to control development.

Replenished XTOL will give you the contrast control with finer grain and smoother tonality.

Thanks, Gerald. How then would one use Diafine to avoid blown-out highlights? Do I measure the subject brightness range, as I usually do with zone system procedures, and then if the highlights are outside of the normal range, use Diafine and assume that it will control any extremely high values?

You may find the following article of interest. When you use Diafine you select the EI recommended for the particular film. After exposure the film is immersed in Bath A for 3 minutes and then in Bath B for 3 min. Development can be considered to be "automatic" in that you cannot change the contrast that Diafine produces. Lengthening the time in either or both baths has little effect and shortening the times will lead to inconsistent results and possible mottling. Some people find this "automatic" development conventient and others much too limiting.

http://www.blackandwhitefineart.net/2011/01/diafine/

Blown highlights occur at exposure, not development, so if that's what you have on the neg, your goose is already cooked, metaphorically speaking. Diafine ain't gonna help (nor will any developer). I know a lot of us wish that it could!

Trust me, 10 or 11 stops of exposure is not something that any B&W negative film is going to support to my knowledge. Better bring that down to 5 or 6, something like that. You could get a little more, but you are in the blown highlight range pretty quickly after that. So we have to expose for what is the priority in the shot and let the rest go, lest we get too far out on that exposure limb.

Just wait for the cloud to cover, or partially cover, the sun. Instant contrast reduction. No?

momus, I am not sure I understand you completely. If blown highlights occur at exposure, then the idea of minus development makes no sense. Reducing development to tame highlights is a common technique. But you are quite right, I don't think I could reduce development enough to cover the contrast range of this particular scene with the bright sunlight and very deep shadows. But I am just trying to get my head around what Diafine actually does and if it will be of any use to me.

momus said:

Blown highlights occur at exposure, not development, so if that's what you have on the neg, your goose is already cooked, metaphorically speaking. Diafine ain't gonna help (nor will any developer). I know a lot of us wish that it could!

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Keep the highlights within the limit of the film and the shadows will be the best that they can.

I have used Diafine with 35 mm trip x. It is a speed boost developer which means 1/2 box speed will get you a very dense neg.

I would use -20% with D76 or Ilfords equavalent.
Alternative is water bath, 4 cycles, developer. water. developer etc.

Stockler or Leica two bath is also possible.

Water you do, run some tests first. Not later asking how do I fix this.

Diafine will develop to exhaustion, without continuing to block up.

This makes it handy for me to develop a variety of films and exposures in one developing tank.

It has other drawbacks though -- not all films work equally well, the results can be quite grainy, and you want to have shot the film to the targetted effective ISO for Diafine. I tested a range of films through 11 stops to determine the optimal effective ISO, and it's often not box speed. (That's sort of the point with Tri-X, the effective ISO is nice and fast.)

filmamigo said:

Diafine will develop to exhaustion, without continuing to block up.

This makes it handy for me to develop a variety of films and exposures in one developing tank.

It has other drawbacks though -- not all films work equally well, the results can be quite grainy, and you want to have shot the film to the targetted effective ISO for Diafine. I tested a range of films through 11 stops to determine the optimal effective ISO, and it's often not box speed. (That's sort of the point with Tri-X, the effective ISO is nice and fast.)

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Tri-X might not be the reference for this exercise as it gives good results through a wide range of exposure. David Vestal made it clear decades ago.

I did a similar test with Plus-X and Diafine and it is difficult to get the best speed. Everything was OK from ISO 25 to ISO 250...

Dali said:

Tri-X might not be the reference for this exercise as it gives good results through a wide range of exposure. David Vestal made it clear decades ago.

I did a similar test with Plus-X and Diafine and it is difficult to get the best speed. Everything was OK from ISO 25 to ISO 250...

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I agree 100%

On many of the films I tested, a range of three stops produced IDENTICAL results.... and useable results over many more stops than that.

I simply picked the middle stop as my effective ISO, to give my the biggest flexibility for exposure error!

Why not flash the shot? Make a pre-exposure using your multiple exposure setting/lever/thingy on the camera body, get some translucent acrylic, hold over the lens for the first shot, expose for about a Zone 2 or 3 exposure, and then make your "regular" exposure? Shooting 35mm, you could load up a short roll and make similar exposures at various combinations. Then develop as you normally would. It will raise your low values and thus compress your negative.

When I was a working PJ in the 70s I carried a quart kit of Diafine with me, in a crunch it can be very useful. When using a hotel bathroom in the 3rd world not to worry about the temperature, timeing, 3 + 3, printable negatives.

As an divided developer it has strong and weak points, I believe that the last edition of the negative AA discussed divided developer to tame high contrast rather than use a water bath method. You may want to look into Berry Thornton's Exactol which can used as either a divided developer or mixed for timed development, there is also divided D76 and D23. I used Exactol, thought it worked well for 4X5 somewhat too grainy in 35mm for my taste.

momus said:

Blown highlights occur at exposure, not development, so if that's what you have on the neg, your goose is already cooked, metaphorically speaking. Diafine ain't gonna help (nor will any developer). I know a lot of us wish that it could!

Trust me, 10 or 11 stops of exposure is not something that any B&W negative film is going to support to my knowledge. Better bring that down to 5 or 6, something like that. You could get a little more, but you are in the blown highlight range pretty quickly after that. So we have to expose for what is the priority in the shot and let the rest go, lest we get too far out on that exposure limb.

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Sorry but this is bad advice. The exposure does have an effect on where tonal values are placed but it is the development regime (developer, dilution, inversion technique, time, temperature) that determine where the densities will build. For example, if you heavily expose a film to retain shadow details and then over develop you will have unprintable highlights. However, if you do the same exposure and use a -development (in Zone System terms) or a water bath or divided development or a two-bath developer, etc you will have a good negative.

For example, I always expose so that an area that I wish to render as Zone III (dark shadow area with some detail) will be recorded on the film and then process in Barry Thornton's Two-Bath developer. This always gives me the subject detail that I want with no blocked highlights. It is really that simple.

I, for one, would not use Diafine for three very good reasons:

• Availability is very patchy.
• It produces some very odd results with most films other than Tri-X.
• Other than extremely high contrast scenes, it can often deliver a very flat negative.

Bests,

David.
www.dsallen.de

momus said:

Trust me, 10 or 11 stops of exposure is not something that any B&W negative film is going to support to my knowledge. Better bring that down to 5 or 6, something like that. You could get a little more, but you are in the blown highlight range pretty quickly after that. So we have to expose for what is the priority in the shot and let the rest go, lest we get too far out on that exposure limb.

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No I will not trust you and I do not trust you. By using box speed not IE and following the instructions for replenished XTOL I can get 10 or 11 stops on the film if the SBR is there. The problem is working the magic to get those 10 or 11 stops on to paper. Perhaps you would like to come out to Los Angeles and I will teach you about photography.