PMK or Divided D76

[paul2]

Do those with experience using PMK and divided D76 have a preference for one over the other in terms of its ability to produce a good long scale negative with adequate highlight separation?

 

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I ask as I am considering D76 as an occasional alternative to PMK.

 

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Thanks,

Paul

[pete_caluori]

Greetings,

 

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I've not used PMK, but instead use ABC+ Pyro; the formulation varies

only slightly. IMHO if your desire is a long scale neg, with

highlights that do not block, then Pyro is the way to go. Divided

D76 is a good developer and certainly easier to use than Pyro, but I

have seen instances where highlights became too dense. Granted it

doesn't usually happen, but it can. Pyro OTOH is more tollerant in

that regard.

 

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Regards,

[scott walton]

I have used DD76 extensively as well as Diafine and love them. The

tonal range is superb and the added acutance of Diafine is beautiful.

They both are extremely fine grain and really don't overdevelop due to

their compensation. I haven't done the PMK so I really cannot give my

opinion on that or any Pyro developers.

[dave_karp]

Scott,

 

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I am just getting ready to test Diafine after not using it for many,

many years. (My Dad taught me how to develop film with it when I was

a child.) What film(s) do you use, and what EI do you use? Sheet or

roll film? Do you adjust the EI to alter contrast? What type of

photography do you do?

 

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Thanks in advance.

[ted_kaufman]

I've never tried divided D-76, but I can offer that PMK is made to

order for the needs you've described. Developers based on pyro (PMK)

and catechol are particularly suited to long scale subjects that

require defined highlight separation.

[brian_ellis3]

I've tested PMK extensively and compared it with identical negatives

developed in D 76 (not divided D 76). There was no visible difference

between prints made from PMK negatives and prints made from negatives

developed in D 76. Others have made the same comparison tests using

HC 110 with the same result. Despite the aura surrounding it, the

objective testing I've done and seen done by others doesn't support

the idea that PMK negatives result in prints that are visibly

different in any way from prints made with negatives developed

normally. So my suggestion would be to ignore PMK given its trouble,

expense, and toxicity, and just use divided D 76. My only

qualification to this is that when the testing was done (last summer)

we were following Gordon Hutchings' recomendation to rinse the

negatives in used PMK for two minutes after fixing and before

washing. Since that time I've heard three different knowledgeable

people say that this step should be omitted because it just adds

overall density rather than proportional density. I haven't yet done

any testing with that step omitted. If anyone has, I'd like to hear

from them.

[ted_kaufman]

Brian: I don't know how controlled your test conditions were in which

you compared the relative merits of D-76 and PMK, but from reading

your post one might conclude there is no difference in the tonality,

scale, sharpness and grain between a print from a D-76 negative and

another from a PMK negative. And by extention from your comments,

there is also no difference between HC110 and PMK, thus no difference

between HC110 and D-76. From your post, one would conclude there is

no diffence in developers at. You're joking, right?

[brian_ellis3]

I guess I wasn't clear so I'll try again. My test procedure consisted

of first determining developing times for PMK (I already had those

times for D 76 since that's what I've been using for years). After

doing that, my testing procedure consisted of making a series of two

identical negatives of various subjects, developing one set in PMK

and one set in D 76, then making prints from each set of negatives. I

could always make a print from the D 76 negatives that was visually

identical to the print made from the PMK negative. In other words,

PMK wasn't imparting any special qualities to the prints that I or

anyone to whom I showed the prints could see. Two friends of mine

were doing the same thing at the same time, more or less

independently of me. One of them was using HC 110 instead of the D 76

that I was using. He too could match prints made from his HC 110

negatives to prints made from his PMK negatives. I wasn't saying that

all developers are identical, only that the results obtained from PMK

seemingly can be obtained with at least two other developers (D 76

and HC 110). Hopefully that's clear. If not, let me know and I'll try

again.

[dhananjay_n]

I'm afraid I DO see a lot of differences between negs developed in

D76/D23 type developers and staining developers. And I would come

down on the side of the staining developers for long scale subjects.

The main reason has little to do with the stain and more to do with

the tanning action of pyro and catechol. The tanning action means

that these are surface-acting developers.

 

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The biggest problem I have encountered with conventional developers

of the D76 type is the fact that the develop in the depths of the

emulsion as well as the surface - this means that irradiation is a

huge problem. Keep in mind that irradiation is a bigger and bigger

problem in the more heavily exposed areas (even in the so-called thin

emulsion films). Thus, acutance is severely curtailed in the heavily

exposed areas. Most people complain about 'blocking'. This 'blocking'

is not due to the highlights ending up on the shoulder of the curve

(modern films go on for a long time before hitting a shoulder).

The 'blocking' is really due to irradiation within the emulsion which

reduces acutance and results in highlights with no textural content

at all. Keep in mind that this is further exacerbated by the solvent

action in the D76 type of developer - silver (on the surface and in

the depths of the emulsion) is etched away by the sulfite and

replated back. Hutchings says that microscopic analysis shows a

silver speck and a large diffuse area (presumably the replated part).

 

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Staining developers tan the gelatin and as a result are surface

developers. This should be quite apparent - a negative developed in

pyro or catechol looks unreally sharp, due both to the fact that

there are enhanced adjacency effects, and the fact that the surface

acting nature means that there is little loss of acutance to

irradiation. More importantly, the fact that there is no irradiation

means that the highlights maintain texture - the acutance that is

essential for providing detail and texture in areas is not destroyed

by irradiation in the emulsion.

 

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Given the toxic nature of some of these chemicals, it would be great

if the results were achievable in some other fashion. But I'm afraid

I haven't seen that. Compensating development of any kind (water

bath, divided development, dilution, reduced agitation) basically

puts a shoulder on the film curve. While it may allow highlights to

be printed, the highlights will have reduced local contrast due to

the lower slope in the shoulder that has been put on the film curve.

Staining developers don't put a shoulder on the curve but provide

enhanced acutance, even in the highlights. In other words, the

gradation genuinely seems better.

 

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Cheers, DJ.

[ted_kaufman]

DJ: That was a remarkably cogent analysis. Moreover, my own

experience using PMK and catechol developers supports your findings

precisely.

 

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High SS content developers like D-76 and D-23 consistently yield

bright, bald highlights compared to negatives developed in tanning

developers. But there is more: I've never seen any variation of D-76

or D-23 achieve the richness or smoothness of midrange values

characteristic of PMK and catechol developers. That is not to say D-

76 will not produce good images, but it surely does not look like

PMK, et al. Also, edge acutance and micro detail are crisper and

obviously superior with tanning developers, and this, due to the

masking effect of stain (which clearly contributes to the illusion of

tonal smoothness), is achieved without the apparent graininess

typical of high acutance developers--especially in skys and other

highlight areas because they don't require extensive burning to hold

texural detail.

 

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Brian, if you've never seen these differences, I'm sorry.

[brian_ellis3]

DJ - When you say you see a difference, do you mean you've made a

series of identically exposed negatives, developed one set in PMK for

the "correct" PMK time for the contrast range of the scenes in that

series of negatives as determined from proper testing, and the other

set in a "normal" developer for the "correct" time for that developer

as determined from proper testing, made the best print you can make

of the PMK negative, and then were unable to duplicate that print

from the "normal" negative? (i.e. your PMK prints were visibly

different in some way from your "normal" prints despite your best

efforts to make them appear identical). If that's what you're saying

I'd like very much to see several of the comparison prints you used.

If you're agreeable let me know by e mail and I'll send you an

envelope with the postage prepaid so that you can send the prints to

me and I'll return them to you in a couple days. I don't mean this

sarcastically or as a snide "I dare you" challenge, I'm seriously

interested in seeing your results because three people, two of us

reasonably knowledgeable photographers and the third a photography

teacher, tried to do this and we were unable to do it (i.e. we could

always make a print from the "normal" negative that duplicated the

print from the PMK negative). OTOH, if this isn't what you've done,

and if instead you're just looking at some negatives developed in PMK

and concluding that they look "sharper" or "better" than some

entirely different negatives developed in other developers, then I

don't think your observations are very significant or valid. Even

assuming you can draw valid conclusions about two developers by

looking at a random bunch of entirely different negatives (which I

don't think you can do), if the differences in the negatives don't

translate into differences in the prints, then who cares what the

negatives look like?

[james_conrad]

There is an interesting article on www.unblinkingeye.com called the

effects of Pyro Stain. While this article is concerned with the

results of pyro VS D-76 for platinum contact printing it might

provide some insight for those interested.

 

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Cheers

[dhananjay_n]

Hi Brian

 

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I should preface this by saying that I don't consider my testing very

exhaustive or anything of the kind. I was more interested in finding

something that worked for me and getting on with making pictures.

What I stated above was my understanding based upon both the test I

did, and in looking at a large number of negatives that I have shot

and developed in the different developers. Details about test below.

However, as much as I like data based upon tests, I think the second

part (my subjective opinion based upon comparing different, non-test

negatives) is important also because we shoot varied scenes. And the

kind of scene doesplay a part in determining whether a particular

variable (type of developer) makes a significant difference or not.

And it is something that would be too onerous to test, so I fall back

on my comparisons of negs.

 

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First, the test. Yes, I exposed a few scenes and developed them in a

Catechol developer and D23. The basic idea was to develop them to the

same contrast - I used the methodology Phil Davies outlines in his

book. What I find is that for 'normal' scenes (i.e., a scene

consisting of about 5 stops for luminance differences - typical zone

III to zone VII kind) and a decent amount of texture, I could not see

any differences between the two developers (both in the negative and

in the print) - there were some differences, very subtle stuff that

could be as much due to minor differences in curve shape etc (see

below) but nothing dramatic. Depending upon the kind of scene etc.,

you may find a difference in that one developer may exhibit enhanced

acutance or adjacency effects etc., although this is going to depend

upon the scene and how much detail there is and so on. However, when

it comes to other kinds of lighting situations (e.g., a long range of

luminance values, a contraction negative, low local contrast in the

highlights), the staining developer held texture in the highlights

more easily.

 

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Caveats: There were some other differences between the two

developers. Most importantly, I'm afraid given my processing

conditions, I could not get idential curve shapes, the D23 did have a

shoulder compared to the Catechol developer.

 

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Two negatives (not part of my test) that reveal this most clearly (to

me) are pictures of ice on a lake with the glare of the sun on the

ice in one area. The D23 negative is 'blocked', if I expose the

negative enough to print through, I get a textureless 'grey' - I

interpret this as meaning that irradiation within the emulsion has

reduced local contrast in this area considerably. However, the

Catechol developed negative prints with texture - I interpret that to

be due to the tanning that prevents irradiation.

 

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I did not mean to imply that your tests were wrong. I was merely

adding another data point to the discussion. It is entirely possible

that there is something idiosyncratic such as 'kind of scene' that

determines whether one will see differences between developers etc.

And I think the point you make is a valid one. If the kind of

pictures one wants to make does not benefit from staining developers,

there is little to be gained by going to PMK or anything like that.

Hutchings himself states that pyro's advantages tend to reveal

themselves in 'difficult light' - I interpret that as meaning that

certain kinds of light and certain kinds of scenes will be handled

more easily in pyro (and I'm sure there are other kinds of scenes

that are more easily handled by other kinds of developers).

 

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Cheers, DJ.

[andreas_carl]

I did fairly extensive testing last Summer, using 120 film (Ilford

Delta 100 and 400) developed either in XTOL 1:1 or PMK. (I took 2

exposures of each scene, one for XTOL the other for PMK processing,

so it was a true side-by-side test). My first impression was, "wow,

these PMK negatives are truly spectacular", which is where some of

the PMK-mystique may stem from. When making carefully contrast-

balanced prints, most of the mystique disappeared. I am not saying

there was no discernable difference anymore between the prints (which

would be surprising, since the densitity curves of film/developer

combinations will never be the same) but I had a hard time to say

which one was "more beautiful". Sometimes the edge went to the PMK,

sometimes to the XTOL print.

When making HUGE enlargments (20x24 from 120 negs) then the PMK negs

always had better acutance. These are some of the sharpest negs I

ever got. They are as good as TMX in Rodinal 1:50, but without the

grain! For LF photographers who don't need to enlarge quite as much,

this may not be important. In MF, I am sticking with PMK though. The

largest drawback to me is not the toxicity (no problem if one works

carefully) but the loss of film speed (a little more than 1 f-stop).

[philippe_bachelier1]

Anyone tried a kind of "divided PMK" ?

This is not a joke or for the sake to try something original.

I have been using PMK since 1996 and I found it gives superior

results than non taning developers in situations of high

brightness range ; otherwise, the results are close, but it is

easier to stick with one developer you know well. I am a PMK

enthousiast ! A good test I made once : take a picture of a

nautilus cut in half (like the one taken by Weston) ; the glaring

surface and the sharp edges of the shell will be shown with

micro details and a subtlety in highlights that is better recorded.

In MF and LF, grain is not a problem with PMK. In 35 mm, grain

matters : you need a beautiful grain wether it is discret or clearly

visible. If you use films not faster than 100/125 ISO, grain is not a

problem with PMK. But for 400 ISO in 35 mm I find the shape of

the grain in the shadows too similar to what you get from an

underexposed color negative film : disturbing. Well, a D76 grain

is more beautiful in this part. I like TMY for 35 mm ; I won't say it

is the best film : I like it. I tested all 400 ISO, and found I prefer

this one in 35 mm because of the resolution, size and shape of

the grain. Once the contrast of TMY is controled, I find it a good

film. TMY has the same problem of grain in the shadows than

any other 400 ISO film in PMK. I like to take pictures with

"contre-jour" or high brightness range ; and PMK does a good

job in highlights. I wondered if Divided D76 could give me the

grain of D76 with the highlights of PMK. I tried but the grain was

there but not the same quality of PMK highlights. TMY can record

a lot of information in highlights, but divided D76, while keeping

highlights with details, those details were flater than what I get

with PMK. To get advantages of both developer, I tried a divided...

PMK. For the first bath, I use 5 g of metol with 50 g of sulfite. For

the second bath, PMK. 4 mn in bath A (70°F/21°C) and 4 mn in

PMK. No rinse between the two baths, like any two baths

development. I use an alkaline bath after fix (as in the PMK

procedure). The negatives have a stain, but not as much as with

a normal PMK development. The result ? I get the grain I like in

the shadows and the highlights print with all the details I am

looking for. Contrast can be controled with varying times in A and

B or with temperature : low contrast : 3+3, high contrast : 5+5.

It would be interesting to have your opinion on that subject.

And be lenient with my English...