NEW 8x10" Film Processing Tank

David M

Well-Known Member
Registered User
I seem to have been able to download a copy of Mr Anchell's book.
Thank you Steve.
On Page 40, under the heading Developer Volume, he quotes Kodak as saying that 150ml of developer is the minimum for 80 sq ins of film. Then he asserts that for "full and complete development" we should use more. And somehow, we arrive at 250ml. Why not 300? 500?
Two points arise. Firstly, which developer? It cannot be a universal rule or some developers would require a bathtub. On page 41, it seems that he is assuming D76.
More importantly perhaps, we do not subject negatives to "full and complete development". Prints, yes, but negatives are developed to produce a desired level of contrast, not maximum possible density. That's half of the Zone System. We can use agitation, temperature, time and dilution as we choose. Dilution is only one factor. Mostly, we use time.
For LF photography, there's another factor. A roll of 35mm film (nominally 80 sq ins) may be assumed to have a variety of images with an average overall density. An LF negative would consume different amounts of active ingredient for different subjects – cats in coal cellars and brides in snowdrifts.
I have to admit that this is a last-minute thought and I don't know how significant it is.
It would be relatively easy to test Mr Anchell's assertion in the Stearman 10x8 tank. Not me, or rather, not at the moment.
 

Alan9940

Active Member
Registered User
David,

Valid points! I would be the first to agree that more developer is generally better than less. However, I don't know how one arrives at an arbitrary volume of 150ml. HC-110, for example, needs 6ml per 80 sq in (see my post above.) Pyrocat-HD works successfully at minimum levels, too; I routinely use 6ml of developer (A) and 4ml of accelerator (B) to 1L of water to process a single sheet of 10x8. I'm sure other photographers have their own levels of developer concentrate that they feel comfortable with.

It's all a very easy thing to test, if one is so inclined. Determine your own personal EI using a starting development time from, say, the MDC. Mix what you believe to be plenty of developer concentrate into your working solution (250ml, per Anchell.) Then, determine your own accepted development time for the high values; I use a densitometer to measure Zone VIII, but correct development time can easily be determined in the darkroom. OK, as my photo mentor used to say, "Now, ya got one foot on a rock." Using your now hard earned knowledge about your film stock, start reducing the developer concentrate watching for that point where the high values don't develop fully, low values start loosing definition, and/or the negs simply look too thin. And, Bob's your uncle (sorry, do y'all say that on your side of the pond?)
 

Sverre

New Member
Registered User
Ad developer minima: I reread what Anchell/Troop writes in "The Film Developing Cookbook", page 31 in my edition. The starting point is a Kodak claim (this is in the late 90-ties) that 100 ml undiluted D76 is sufficient to develop one 8x10 sheet (or roll) of film but adds (and this seems to be a Kodak quote) "it may not always be enough to develop the film to it's fullest potential. The amount of solution required to cover the film's surface should not be confused with the amount of developer required to fully develop a roll of film". So there are/were several Kodak sources. This is why I was concerned with SP-810's potential solution volume. I'm not a photochemist, but my empirical experience has led me to use rather more than less of the often recommended developer volume. Some other users, as this thread shows, have different experiences. I have nevertheless decided to by an SP-810 to develop 5x4 and look forward to reporting my findings.
 

David M

Well-Known Member
Registered User
That seems the best solution (Oops, not intended). Will you be able to share your findings with us, after a long enough trial?

The distinction between covering and developing seems sensible.
I haven't handled a Stearmen 10x8 tank, but my worry with large amounts of solution would be splashing it out during agitation.
Stearman Press are in the final stage of producing their own developer, which they claim is formulated especially for LF. I know no more than that.
 

Ian Grant

Well-Known Member
Registered User
The figures given for volume of developer take into account the amount of developing agents used and the level left after a specific time. It gets complicated because Kodak's figures for D76 are how much developer is used in a replenished system so is less than say processing one sheet of 10x8 film in a tray.

In the 1950's Ilford did a lot of work on the actual levelos of depletion of various chemicals including developing agents, this was part of their research into producing a PQ version of ID-11/D76 published as the Axford-Kendall PQ Fine Grain developer and marketed as Autophen. Essentially the major issue with ID-11/D76 replenished is the Bromide build up suppresses the action of Metol so you need an inefficient bleed system or replemnishment. Phenidone tolerates Bromide to a far higher level so Autophen used a simpler top up replenisher, didn't collapse over time so was used in large scale D&P labs, there was also a bleed replenisher for older machines.

There is an optimal level of developing agents need for a film so the greater the dilution the higher the volume needed or you get compression when the level drops and retards development of the highlight areas.

Ian
 

David M

Well-Known Member
Registered User
A simple test would be to expose two 5x4 negatives identically. I suppose a "normal" scene would be best. One would be developed alone in (shall we say?) 500ml of developer and the other in a batch of four, taking care over temperature, agitation and so on. A factor of four should show up any significant differences. Best to clip a corner off one of them. Then it's onto the scanner or densitometer or perhaps make two straight darkroom prints with identical times, processed together at the same time. And with luck, onto the forum.
It's more work for someone else, but if there are observable differences, the next step would be to make "best possible" prints (this time with the full repertoire of printing techniques) from each negative to see if there is any significant difference in the final result. If one neg needs another half grade or a couple of seconds more, I'd count that as negligible. Others may be more fastidious. Scanning and digitally printing would be a parallel route.

It does seem that there are several alternative narratives about this and probably no definitive answer. We do seem to have established that many successful photographers do not follow Mr Anchell's advice.
 
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