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Chris Gittins
9-Jul-2004, 21:05
The specific impetus for this post was the article in the July/August View Camera on PMK vs Pryocat HD. The bone I have to pick isn't specific to the materials discussed there. The prints which accompanied the article just raised an issue that's been on my mind for awhile: How does one make an appropriate comparison between negatives developed in A vs B, prints developed in C vs D, printed on paper E vs paper F, etc.? I don't mean that as a rhetorical question. What common _objective_ characteristics must A and B, C and D, etc. possess in order to meaningfully compare them? I'll limit my comments here to comparison of prints, but the same general considerations hold for negatives as well.

Picking on the prints in the View Camera article for a moment - with apologies to Steve Simmons, as I appreciate the objective of his article and the prints in question are only one example of a widespread phenomena - the prints made from negatives developed in A and B appeared to be printed differently. (For the purpose of this discussion its immaterial which was Developer A and which was Developer B.) The prints made from the negs developed in A are significantly darker than the negatives developed in B. You can tell its not simply an overall contrast effect because both the shadows and highlights are darker. With one print being darker than the other, I found it very hard to tell whether one negative was really giving better highlight or shadow separation or whether it was just an overall print density effect. If you print Zone III down to Zone II, then loss of shadow detail is no surprise. Neither is an apparent improvement in highlight separation if you print VIII down to VII, etc.

And that gets back to question of how you make a meaningful comparison of any two prints. It seems to me that if you want to do meaningful apples-to-apples comparison, then you have to pick at least two tie points (Zones) where the print densities match, e.g., Zone III and Zone VII. If you have one print darker than the other, it's going to be much harder to make that comparison. I'd imagine it can be done, but the difference in overall density is a big distraction. Do others concur that you want to match both a shadow Zone and a highlight Zone in the prints you're comparing? (Paper white and Dmax don't count.) I don't see another way to make a good comparison of highlight/shadow separation unless you have tie points. For example, if you don't, then how do you know the perceived effect isn't due simply to a mismatch in paper exposure scale to negative density range?

Other thoughts?

Chris

Keith Fleming
9-Jul-2004, 21:54
The reality is that all technical articles in magazines must be evaluated by the reader based on experience and judgment. Magazine reproductions, no matter how good, are not the same as the original prints. Those are not "prints" in the article--they are at least two generations away from the original prints. The originals were scanned, and that process may introduce slight differences. Another step is the printing onto paper. It's quite possible that the quality of printing may vary at times during the press run of an issue of a magazine, so your copy may not be the same as mine. Given the variables, the recourse is to read the article, study the illustrations, make a judgment call on the accuracy and validity of the article as a whole, and then study your own tests (which you may have done long ago). It's to be expected that you and I will not always agree with an author's conclusions; after all, we in the large format community can't even agree on which large format camera is best. The article is part of a dialogue that includes this forum, and that's a healthy thing.

Alex Hawley
9-Jul-2004, 22:24
I thnk you're right on the point Chris. I haven't read the article so I have no opiions on it. However, its a fundamental point of any scientific or near-scientific test that the number of variables must be minimized. Prefferably, there should be only one variable. Many times, that's not possible, so the other variables that are not being tested must be accounted for.

Here's how I did a test between Pyrocat HD and ABC pyro. First, I made 2 negatives of the same subject. The only difference in exposure was speed rating since the concensus of the time was Pyrocat allowed an extra stop of film speed. Of course, both negatives are from the same box of film.

Both negatives were developed by inspection in the different developers, noting the development times. Here's the major difference we are testing for and we know what and why it is.

Printing is done on the same paper. The ABC negative is printed first. Several trials are made until I feel I have a good print. The Pcat neg is next and exposed for the same time as the ABC neg. As to be expected, the exposure is not good for that respective negative but it does give a good measurement of the density difference between the negatives.

Then I proceed to get a good print out of the Pcat neg. Now we know the exposure time difference (remember, same paper and paper grade). After everything has dried, we can make a judgement on which negative printed best, and the differences between the two in processing are known and not subjective.

I wind up with only one variable besides the developer which is the point of the test; that was developing by inspection. Knowing the relative inaccuracy of the method lets me make a better judgement in comparing the prints resulting from the two developers.

Alex Hawley
9-Jul-2004, 22:28
Keith's point on trying to compare the prints in magazine is a valid one too. Its an exercise in futility trying to show subtle differences when the images are at least 2 or more generations from the original. Better to describe the diffrences in words.

Jorge Gasteazoro
9-Jul-2004, 22:29
IMO if you develop the films to the same contrast index, print with a fixed grade paper (not variable contrast) and expose the paper to the same time for all negatives, differences in the way the developer acted are seen on the prints.

I agree with Keith that a magazine reproduction might not be the best way to judge differences in prints. OTOH, the prints should look somewhat similar, maybe some change in contrast, but they should not look far darker or lighter.

Without having read the article let me make some guesses:

PMK was the better developer because it had better contrast, better edge effect and had the same speed as Pyrocat HD (Which is totally ridiculous).

If there was no sensitometric data to back up these claims, what you are reading is an opinion based on the authors eye balls, not an article comparing two developers.

Alex Hawley
9-Jul-2004, 22:40
Exactly, Jorge. I don't have any sensitometry equipment so I know I can't get an exacting match in CI. I try to compensate by making the best print I can from each negative. But the outcome, as you say, is still an opinion.

Jay DeFehr
10-Jul-2004, 03:33
While View Camera magazine would probably be the last place I looked for an objective comparison of anything, I think it's important to keep in mind what we are trying to compare. When we compare film developers, what is it about the developers that we are comparing? Film speed? Activity? tendency to fog? Grain formation? Stain color and proportionality? These attributes combine to characterise a staining developer, and each is measurable. I contend that a table listing these attributes for each developer and common films would be far more useful than the "proof-in-the-pudding" methodology of making prints for comparison, which introduces so many variables that nothing of value can be gleaned from the exercise. I think it's possible that some readers of View Camera don't really want to be confronted with raw data, regardless of its validity, and prefer to take the advice of an "expert", with nothing more significant than a few magazine reproductions and a testimonial to make the case for them. Mr Simmons finds himself in a quandary; how to qualify himself as an expert in the face of criticism from legitimate experts without doing the necessary work, that even if he were capable of, runs the risk of alienating too many of his readers. I don't envy him his position, and wish him the best of luck with his publication and reputation. In the meantime I will continue not to look to VC or its editor for objective, meaningful information.

Jorge Gasteazoro
10-Jul-2004, 03:54
Well yeah Alex, but if you are going to publish a comparison I would think you would want to provide hard data, not just, well this is how it looked to me.

Now my take when I did this was that if you take the time to produce a best print out of each negative form each of the developers, then there would not be any difference, all 3 were equally capable of producing outstanding prints. That is not proof that a developer is "better". The "proof" if we can call it that is which one produces the best first work print without any manipulations.

My observation was that if I wanted, I could have made excellent prints from each of the negatives that would have been virtually indistinguishable.

My conclusion was that WD2D (old formulation) produced the best first work print with the best film speed, but really with a little bit of extra work, all would have been equally good.

Chris Gittins
10-Jul-2004, 04:28
Just to reiterate, my point doesn't have anything to do with specific developers - PMK, Pyrocat, or otherwise. Keith makes a good point: magazine reproductions are several steps removed from the original prints. It should be no great surprise if there are significant discrepancies between the reproduction and the real thing.

That said, when you're doing your own testing, do you pick a couple of 'tie points' as I suggested above - which might necessitate changing paper grades if you're comparing negs where different development yielded different CI's? Do you go with Jorge's approach: develop to identical contrast index, print on fixed paper grade for identical times? Do you use a different approach? Are you as concerned about overall print brightness as with overall contrast? I'm interested in hearing what other people feel rates as an apples-to-apples comparison when comparing prints.

Chris

Nick_3536
10-Jul-2004, 06:16
Expose two negatives of a scene you know well. Process and make the best two prints you can. Look at the prints. Pick the one you like best. While I'm sure getting hard numbers will reduce bias but if in a blind test one print looks better to you isn't that the only thing that matters? I can understand if you're doing the test for others the need to produce hard numbers but if you're testing for yourself then shouldn't the test match your wants?

N Dhananjay
10-Jul-2004, 07:38
I must confess I was quite under-whelmed by the article as well. I noticed many of the same things mentioned above. In addition, I'm afraid I consider the article methodologically unsound.

A comparison of two developers is a complicated thing to do, because as Jay pointed out, there are so many dimensions to compare them on. To make menaingful comparisons, you typically want to control everything else except the dimensions of interest in a particular test. For example, if you want to test the film speed yielded by two developers, you have to develop them to the same CI etc. What this means is that a comprehensive comparison of two developers requires multiple tests across a variety of fronts. A really rigorous comparison would involve multiple measurements to make sure small differences are significant and not just due to random error, but with the reseach labs at Kodak gutted, I doubt anyone is going to have the patience/money to do that. At the least, one would require some level of experimental control. That would give us a theoretical understanding of the differences between the two developers.

Unfortunately, not everyone is comfortable with interpreting theoretical results and translating them into practical situations. That means some folks prefer to make pictures with the two developers and evaluate the results. Whether those results can show up in magazine reproductions is most unlikley. The biggest problem with this approach is the fact that there are interactions with subject matter. That is, one developer might naturally do much better with certain subjects than another and if that is the subject you shoot, you have skewed the results of your tests right off the bat, which is why I personally think this is methodologically not sound. It is absolutely fine if it is one individual trying to choose a developer to work with because s/he is interested in choosing a developer for his/her subjects. That is, the conclusions s/he draws are indeed constrained to the subjects shot. But in this case, there are generalizations being made that cannot and should not be made. Having used both developers a fair bit, I am highly dubious whether there are substantial differences between PMK and Pyrocat on the reported dimensions.

Cheers, DJ

neil poulsen
10-Jul-2004, 10:53
I don't know too much about pyro, having never tried it. But statisticially, this problem fleshes out fairly simply. For discussion, let's say that we have three responses, three different characteristics that we want to evaluate.

Contrast

Brightness

Edge Effect

In addition, we have two developers, Pyrocat HD and PMK, and we would like to evaluate the effect that these developers can have on the each of the above responses. We will need to determine a method to measure each of the responses, and likely, these methods will be different. One can't measure Contrast in the same way that they would measure Brightness.

So, we conduct and report the results of three separate experiments to determine how these developers affect each of the responses. (An experiment to compare Contrasts, a second to compare Brightnesses, and a third to compare Edge Effects.) This may sound simplistic, but I think that readers interested in pyro would like to know this information. They would find it useful. As DJ points out, there are subtleties, but the overall structure is straight forward.

The trick in all this is in addressing the question, "Which developer yields the most effective print?" This is indeed a trick, because this evaluation requires assessing all three responses at the same time, in the same set of prints. As to the method for making this comparison, one might photograph a given scene with the same brand of film, but developed in each developer. Then, perhaps the same printer would print the two resulting negatives the best way that he/she could, using the same print developer and paper. The printer should not know the source of each negative. A panel of viewers could evaluate the final prints (not knowing which is which developer), and these prints and the panel's comments could be included in the article for the reader to digest.

Of course, there are some problems encountered in the preceding paragraph, as there will always be. There's variability in how the printer would print each negative. Another problem is that perhaps one developer would favor cloud scenes during the day (e.g. John Wimberly), whereas another developer might favor night photography. So, pick whatever approach seems best. The important thing is that these problems should be pointed out in the article. If the reader knows the circumstances of each comparison, how it was done, the weaknesses, etc., they can then draw their own conclusions. One could do a study for both cloud scenes and night scenes, but if the article goes on endlessly, it loses its value. At the very least, the reader knows that each developer can yield good results under some circumstances. Or, perhaps the comparisons done might show that one of the developers is indeed inferior?

I think that including final prints in some context is worthwhile. After all, it's the final print that really counts. How final prints are affected will be a question in the readers' minds. As a statistician, I'm inspired by the work of Richard Henry in his book "Controls In Black and White Photography." He was a research chemist who applied his research methods to better understand B&W photography. He would frequently include final prints in his evaluations and have them evaluated by a panel of independent viewers. We may find no substantial differences, but that in itself advances our understanding.

Jay DeFehr
10-Jul-2004, 11:01
DJ, you make a lot of sense, as usual. I doubt wether the differences in developers of the same class are substantial enough to be important in practice. I am interested in the kinds of measurable differences noted above as a means to fine tune developer formulae, but my main criteria for developers of a common class are keeping properties and economy. If I can make up a concentrated solution that will develop hundreds of rolls of film for a few dollars, and that will last indefinitely on the shelf, I can learn the intricacies of that developer without the variations introduced in the making up process. It seems that a lot of the debate is centered around the championing of one formula over another, rather than personal use. I will try to make the kind of comparison that I noted in my previous post between the two developers that I'm currently working with, for my own personal information, but I will happily share whatever information I glean with anyone who is interested.

sanking
10-Jul-2004, 11:42
DJ makes many good points. Most especially as regards the importance of developing comparison negatives to the same CI, and to the importance of subject matter.

There are several areas of particular interest in film testing: apparent sharpness, appearance of grain, and effective emulsion speed. With staining developers you also have the question of how the color of the stain interacts with the sensitivity of a particular paper.

I have always been interested in comparing different films and developers and over the years have done quite a bit of testing. And since I don’t like to waste my time with meaningless comparisons I try to use sound methodology, which includes the use of sensitometry in the initial stages to assure that comparison negatives, whether for film or developer testing, are always developed to the same contrast, or CI. This is very important because the CI to which a negative is developed affects not only effective film speed but also sharpness and the appearance of grain. Even a very small difference in CI could potentially result in a big difference in all three of the primary evaluation areas.

Some might assume that it would be a fairly easy matter to determine the CI and EFS of a particular film developed in PMK and Pyrocat –HD but I can tell you for a fact that it is really quite complicated. My own comparisons are made in two steps. First, I use BTZS type testing (see Phil Davis’ Beyond the Zone System) and plot comparison curves from transmission step wedge. This data, however, which is based on densitometer readings, is not definitive because of the complication of the stain. So in a second stage I refine the CI and EFS values by matching PMK and Pyrocat-HD step wedge densities. And you need separate tests for indoor and outdoor lighting because films have a different response to different color light.

The next step if fairly routine. You make two negatives of the same scene, using the EFS indicated by your tests, and then develop the negatives for the time indicated by the tests. You should now have two negatives with identical printing density in the shadows and highlights.

Next, you make a print, basing exposure on first maximum black in the shadows. Now you can compare the results and make some meaningful comments. There will be some differences in the rendition of tonal vlaues between prints made with PMK and Pyrocat-HD due to the different color of the stain. The difference will be very small with graded silver papers, but could be significant with VC papers. With regard to sharpness we are now in the realm of the subjective because different observers might well come to different conclusions. For this reason better to have several people comparing results rather than just one. The problem with one observation is that he/she may have an existing bias and see what is already in his/her mind.

If you print with AZO or one of the alternative processes you would need to run new tests.

Over the past several weeks I have been thinking about a methodology that would provide a meaningful comparison of a couple of pyro staining developers with non-staining developers, limiting the comparison to one film but several different kinds of lighting conditions. As I envision the tests at this time there would be three parts.

1. I would determine the CI and EFS for the developers tests and make and develop the test negatives.

2. The negatives would be given to a master silver printer who would be asked to make the best print possible from each of the negatives, but using no dodging or burning.

3. The silver printer would then send the prints to three other persons, all with an established reputation, for visual evaluation.

This project would take a lot of work but it is something that I might be able to use in a book project I am currently involved in so it might be worth the trouble for me.

Meanwhile, the credibility of any evaluation of films and developers will be determined by interested parties based on the methodology utilized and reputation of the person making the tests or reporting the results. That said, my own evaluation of pyro staining developers in terms of the three areas of particular interest are as follows.

Sharpness – When the negatives are developed to the same CI there is no difference in sharpness between PMK, Pyrocat-HD and WD2D. I am convinced that any independent and objective comparison made by disinterested parties will come to the same conclusion.

Grain – There is virtually no difference in the appearance of grain between these three developers in prints up to 20X24” size from 4X5 negatives. Over this size Pyrocat-HD appears to have a slight advantage.

Effective Film Speed – No contest. Pyrocat-HD provides slightly more emulsion speed than either PMK or WD2D. I have been conducting carefully controlled testing of these developers for several years and in my mind there is no doubt about this fact. Steve Simmons appears to have reached another conclusion in his comparison of PMK and Pyrocat-HD, as did Jorge in the article in which he compared PMK, Pyrocat-HD and WD2D. But I stand by my conclusion, with full confidence in the methodology of my testing procedures, and in the knowledge that it is based not on one or two or even three observations, but on dozens and dozens.

John D Gerndt
10-Jul-2004, 12:41
So many people making so much sense!

I am glad to hear that you have a book project Sandy King. You seem like a scientist with an artist’s heart. Have you ever noted how many photographers started out in engineering?

Jay De Fehr has made a keen point as developers do belong in classes (show me the curves!) and one does need to work with each developer for some time to get a feel for what they do.

Now if only I had a large bunch of data to make an intelligent choice with…

Jay De Fehr makes a second keen point about economy. From what I can gather Pyrocat HD and good ‘ol HC-110 are the best in this regard. If Jay De Fehr has something cooking that is even better I might just swing that way but if I respect his first point I must consider staying with what I know…there is the rub!

My thanks to all who share their data; I have learned more about photography and sensitometry this year, through this forum, than I did in the last ten years of shooting in the dark!

Cheers,

sanking
10-Jul-2004, 16:23
John,

Actually I am one of those humanistic types with a Ph.D. in language and literature studies but there is a lingering suspicion in the back of my mind that I should have been engineer instead. But at least my career has given me the opportunity to pursue my interests, which include not only image making but the history and aesthetics of photography as well as image making.

As for the book, those who participate in the AZO forum are already aware of the fact that the book is a joint project with Michael Smith and we will each be contributing to the book in the areas of our greatest interest. In my case that is alternative printing processes, exposing and developing film, use of pyro developers, and digital negatives for alternative and silver processes. I am very pleased with the collaboration because Michael is in my opinion one of the most outstanding photographers of our time working in what I call the pure or straight photography tradition of Weston.

Since both Michael and I are proponents of pyro staining developers a study of the type I suggested in a previous message could be an interesting addition to the book. But if I do indeed do such a study the objective will not to be to prove that one developer is better than another, but to discover and report the differences and how we can take advantage of them. And the methodology will be as sound as I can devise, and the reasons for any conclusions transparent and open to criticism.

Brian Ellis
11-Jul-2004, 17:09
Chris - The way you suggest doing it is, IIRC, exactly the way Phil Davis does it in his BTZS workshops - i.e. he matches the darkest shadow and the brightest highlight from print to print then looks at everything in between to compare negatives and developers (or something very close to that, it's been about 8 years since I attended his workshops). Of course you need a densitometer to do this with complete accuracy and once you say "densitometer" to some magazine editors you hear things like "I'm a photographer, not a lab worker," "some people spend their time running tests, I prefer to spend my time making photographs," etc. etc.

Tom Duffy
13-Jul-2004, 11:55
You guys are making this much too complicated. Pyrocat works flawlessly in a JOBO, PMK doesn't. :)

Kirk Keyes
14-Jul-2004, 10:02
Tom - why do you say PMK doesn't work flawlessly in a Jobo? I find it works quite well.

Tom Duffy
14-Jul-2004, 12:55
Kirk, With 5x7 and 8x10 sheet film in a expert drum, areas of the neg such as clear blue sky often ended up streaked with uneven development or staining. I found I was ruining more negs with PMK than I was helping. I never, repeat, never had a similar problem with Pryocat. As an added advantage, Pyrocat has much less general stain and the negs print in half the time. take care, Tom

steve simmons
27-Jul-2004, 11:51
I have offred to show my PMK and HD negs to anyone who wants to se them. Jorge, who is still claiming to know what is going on with these developers refuses to show his negs claming he destroyed them. Ths destruction apparently happened just after his results began to be questioned. Anyone involved in any type of research knows that you never destroy the original data.

I exposed the fims at my usual PMK EI - 160 for Tri-X and 100 for FP4+. The PMK negs were developed for my standard times and the HD negs were developed according to my tests to get a zone 8 exp to just minimlly darker than pure paper white using a vc paper (Ilford) with no filter which is equiv to a #2 filter. The scans were straight scans from the negs. The PMK negs with both films showed better shadow detail and I liked the elevated high values much better.

Standard & curves do not always show expressive differences in the final print.I am a photographer and express myself in prints not charts and curves. I believe the true test is the final print.

I do need to make a correction in the text where I stated that th HD forumula has Hydroquinone and will do so in the next issue.However, this will not change the results.

steve simmons

Jorge Gasteazoro
27-Jul-2004, 12:42
Ths destruction apparently happened just after his results began to be questioned. Anyone involved in any type of research knows that you never destroy the original data



Once you rejected the article I had no reason to keep them, and the only one who questioned them was you, Sandy King among many others reviewed the article, even though it was not "pro" Pyrocat HD and at least agreed it was an impartially made test with good sensitometric foundation, unlike yours.



I have not read the article, nor do I care to do so, as I am sure the methodology is flawed. But let me make some educated guesses as to your results.



So lets see, you made your film "speed" tests based on Pickers flawed methodology of "minimum time for maximum black." Unfortunately, small variation in this test produce very big errors in results, since they are based solely on the b+f of the film. Developers that give greater b+f density "appear" to have more speed than those that are truly proportional developers like Pyrocat HD. The greater film speed you probably report is due to a flaw in your testing procedures, not because it is true. I suppose I have to explain this to you since you are a "photographer" not a lab tech. To put it simply a variation of 0.01 or 0.02 density units in your test, represents a probable error of 10 to 20%, if the variation is greater then your error is far greater. If you truly want to measure film speed based on a printing time you should use Zone V, not the b+f, as variations of 0.01 or 0.02 in this zone range are negligible.



Lets take the greater contrast you report. Pyrocat HD results in less b+f but is not as energetic as PMK, so for you to be able to compare the differences in contrast, you have to develop the film to the same contrast index, you probably dont understand what this means, simply said, you have to develop the film at different times for each developer, you cannot just put the film in both developers and develop both for the same time. Obviously since you are unable to produce curves, it is my guess all this talk about greater contrast and better shadows is the result of your max black test, once again a flawed result since the films were not developed to the same CI.



Finally anybody doing scientific comparisons should strive to provide the most impartial results based on sound scientific principles. Neither of which you have presented using the excuse you are a photographer not a lab tech.



As to my negatives, dont you worry, as soon as I am done with my exhibition I will be making new ones based on the sensitometry and data I already have and will be publishing it at APUG for everybody to see and compare to your article.



BTW, if you dont like my "personal" attacks analyzing your flawed testing methods, why dont you leave me out of your responses? Cant wait until you have your web site and everybody agrees with you.

sanking
27-Jul-2004, 13:53
Somebody wrote:

"I have offred to show my PMK and HD negs to anyone who wants to se them."

How about sending your test negatives to me, together with all of your exposure and development information of course? I will do an analysis and post my conclusions to this thread.

"Standard & curves do not always show expressive differences in the final print. I am a photographer and express myself in prints not charts and curves. I believe the true test is the final print. "

The print is of course the final test. I too am a photographer and quite a number of persons on this list have seen my work and know its quality. The issue is not one of film testing versus print making. Rather, it is whether the methodology used in your comparison tests of Pyrocat-HD and PMK was adequate to justify the conclusions you reached. I would be able to make that determination to my own satisfaction, based on the conclusions you reached, by evaluating your negatives.

So how about it? Just send me the negatives and I will test them and write up my own conclusions. You can print the results in View Camera if you like, or we can just post them here, as you prefer. Either way I think this step would clarify the issue to the satisfaction of some.

Jorge Gasteazoro
27-Jul-2004, 14:26
With all due respect to Mr. King, I think the negatives should be sent to someone completely impartial to this discussion. People who come to mind are DJ ( I am not even going to attempt writing his name, just so I dont completely destroy it), Fred Newman, Patrick Gainer, Clay Harmon, etc, etc. If any of these or any other person would be willing to volunteer and evaluate the negatives I think it would go a long way to dispel any doubts as to the impartiality of the evaluation. As it stands, evaluations done by Mr. King can be suspect to bias, much as they clearly were shown with Simmons.

Kirk Keyes
27-Jul-2004, 20:36
Steve Simmons writes "The PMK negs were developed for my standard times and the HD negs were developed according to my tests to get a zone 8 exp to just minimlly darker than pure paper white using a vc paper (Ilford) with no filter which is equiv to a #2 filter. The scans were straight scans from the negs. The PMK negs with both films showed better shadow detail and I liked the elevated high values much better."

Steve - I think there is a major flaw in your testing here. You determine development time by printing onto VC paper, and then you proceed to scan the films directly. Did you scan in color and convert to monochrome, did you scan in the green, blue, or red channel as monochrome? You did not say in the article. You say that the VC paper without filtration is equivalent to #2 filter, meaning it is equivalent to Grade #2 paper? Well, I think many people here have compared a stained negative on VC paper with no filtration and fixed Grade #2 paper and they can tell you that those prints are not equivalent.

Can you demonstrate to us that the development time determined with VC papers was appropriate for your scanner? I realize that you can easily adjust the contrast on the scanner's input to match any negative density range, so why even bother determining some sort of development time using VC paper. Why not use graded paper then for your test? And if you are developing for the scanner, do we really care that much about compensating effects since the scanner/software can solve much of this for us?

Also, the scanner will not show the compensating effect of the stain as a print on VC paper could have. They are simply not equivalent. The amount of stain in the negative increase at a higher rate than the density of the silver in the negative. That means the VC paper is seeing more blue than green light in the denser parts of the negative. The scanner cannot easily approximate this response. Do you see the problem with using the scanner and not printing on photographic paper?

You took a big short-cut going from the stained negative directly to the scanner. It is not an equivalent step, and it is ignores one of the major benefits of a stained negative when printed on VC paper. It adversely affected your test in a major way. It is as big of a gaffe as Howard Bond using TMX for his staining test a few months ago that I think we all agreed minimized any affect of the staining developer.

sanking
27-Jul-2004, 22:39
Steve Simmons wrote, and I quote:

"I exposed the fims at my usual PMK EI - 160 for Tri-X and 100 for FP4+. The PMK negs were developed for my standard times and the HD negs were developed according to my tests to get a zone 8 exp to just minimlly darker than pure paper white using a vc paper (Ilford) with no filter which is equiv to a #2 filter. The scans were straight scans from the negs. The PMK negs with both films showed better shadow detail and I liked the elevated high values much better. "

Hi Steve,

Thanks for the clarification. So you determined exposure by printing, and I quote again, "to get a zone 8 exp to just minimlly darker than pure paper white using a vc paper (Ilford) with no filter which is equiv to a #2 filter"? Very interesting.

OK, apart from the issue of scanning, which I will ignore for the moment, why did you base exposure on Zone 8 density, when virtually everyone else in the world bases exposure on shadow density at Zone II or III?

Jorge Gasteazoro
27-Jul-2004, 23:15
I believe he meant exposure of the paper, not the film. IOW, he determined development times for a negative by exposing his negative to zone VIII, develop it to the times his "max black" test gave him and expose onto paper to see how dark/light the print was, if it was too dark then he gave more developing time, if it was too light then he gave less. Of course if the initial "max black" test is inaccurate then the exposure for zone VIII will be too. This is typical Fred Picker convoluted an dreadfully inaccurate testing methodology.

sanking
28-Jul-2004, 00:18
In a previous message to Steve I wrote, "How about sending your test negatives to me, together with all of your exposure and development information of course? I will do an analysis and post my conclusions to this thread. "

Wow, hours have passed and no word yet from Steve!!

So we repeat the challenge!!!!!!

Hi there Steve. How about it? Just send me the negatives and I will test them and write up my own conclusions. You can print the results in View Camera if you like, or we can just post them here, as you prefer. Either way I think this step would clarify the issue to the satisfaction of some."

And, if you wish, I will forward your negatives and development information to a third party for further analysis. To anyone on Jorge's list, or hell, even to Jorge himself if that pleases you.

How much more accomadating can we be?

Ball is in your corner. Put up or shut up.

Jorge Gasteazoro
28-Jul-2004, 01:06
I would like to add Kirk Keyes to that list, he was very helpful to me with the article and he is also very knowledgeable. There is no shortage of impartial people, all that is needed are the negatives........

sanking
28-Jul-2004, 11:09
Jorge wrote:

"As it stands, evaluations done by Mr. King can be suspect to bias, much as they clearly were shown with Simmons."

Bias is always a problem. However, if I have the chance to evaluate these negatives, which I doubt will be the case, the issue is very simple. It is really all about exposure and effecive printing contrast and that is really not something subject to debate. You test shadow values for density and then determine printing contrast, describe the methodology and you are done. If the CI of the PMK and Pyrocat-HD negatives Steve Simmons made have the same effective printing contrast he is justified in reaching the conclusions he reached. If they do not he is wrong. And the issue in a nutshell is really just that simple.

Jorge Gasteazoro
28-Jul-2004, 12:00
I understand and agree with you in the methodology, nothing to it! but if you say he is wrong, many people will say: "Of course he says Simmons is wrong, he created Pyrocat HD!" With my suggestion there are less chances of people saying this. Remember what happened with your post on publishing? Many here thought it was about PMK vs Pyrocat HD, not about integrity in publishing. Lets not go down the same road again, having read Picker's book and knowing Simmons adheres to this testing method religiously, I am very confident his conclusion are wrong, you have nothing to worry about.

N Dhananjay
28-Jul-2004, 12:29
I'd be happy to run the necessary tests. Cheers, DJ

Jorge Gasteazoro
28-Jul-2004, 13:01
I'd be happy to run the necessary tests. Cheers, DJ



Thanks DJ! Well there you go, now all we need is for Simmons to keep his promise and make the negatives available.



With DJ's help testing will be done by a very knowledgeable person totally unbiased and with no ax to grind either way. What do you say Simmons? As Sandy said, time to put up or shut up!

Jorge Gasteazoro
28-Jul-2004, 14:01
Funny, Simmons puts my word in doubt about destroying my negatives, yet not a peep from him about producing his.....like Arsenio used to say....Hmmmmm

sanking
28-Jul-2004, 14:47
"I'd be happy to run the necessary tests. Cheers, DJ"

You have my vote.

Kirk Keyes
28-Jul-2004, 19:45
Sandy King wrote "It is really all about exposure and effecive printing contrast and that is really not something subject to debate."

That's sentence sounds pretty straight-forward and simple, but I think it is really just too simplistic. While I think it would be really interesting if Mr. Simmons were willing to allow a 3rd party to do some testing, I think that testing would be for naught unless there is a strictly defined set of conditions, guidelines, and goals for these tests and that they are described before any testing is done.

So Sandy, since you made the claim I quoted above, I would like to hear exactly what your proposed testing method would involve. This will be of great benefit to DJ if he does get some negatives to test. Does DJ have the proper tools to do the testing, i.e. a densitometer, both reflected and transmission, is his densitometer calibrated to an acceptable level... Also keep in mind that Mr. Simmons may not have any negatives containing step wedges, only pictorial images.

We may certainly find that there is much to debate as far as defining our as to yet unagreed-upon testing method.

As far as Mr. Simmons not having replied back to this thread, I would like to suggest that everyone keep in mind that we all have schedules with probably widely varying time constraints that may preclude us from making a timely reply...

Jorge Gasteazoro
28-Jul-2004, 19:59
As far as Mr. Simmons not having replied back to this thread, I would like to suggest that everyone keep in mind that we all have schedules with probably widely varying time constraints that may preclude us from making a timely reply...



That wont fly Kirk, he has the time to argue with me and accuse me of sending him a "false" article, whatever that is...lol....



You raise some good points, but I think what Sandy is suggesting is that two negatives, developed to the same CI, should have very close density ranges once b+f has been zeroed out. I dont think it needs to be that complicated, all we need are two different readings from each negative. In addition, on the same subject, two negatives developed to the same CI should be able to print equally in a graded paper. Printing them on a VC paper with no filter is not "kosher" as they say, as the stain of one or the other might give it an unfair advantage in tonality.



Anyhow, in any case it seems a moot point, I dont think Mr. S, will provide any proof of his claims.

Kirk Keyes
28-Jul-2004, 20:23
Hi Jorge, I'm just trying to point out that he may be involved in something more important than to sit around and argue with someone on some internet forum. I know I am sometimes!

But about the testing - OK, so we think we want to have the films processed to the same CI - are we going to use the Blue channel or visual channel? How do we determine that they ARE at the same CI if they do not contain step tablets? Is graded paper really the best thing to print on as many of us only use staining developers because we DO intend to print them on VC paper. You say it is not "kosher" as the stain may give one an unfair advantage, but I suggest that measuring that unfair advantage is precisely what we are trying to do here with our testing. So I may say that using graded papers may not be the right appoach.

It is these sorts of questions that I think need to be very carefully laid-out before any testing gets done.

PS - I'm glad this thread was revived as I believe it was forgotten long before the subject had been discussed enough.

Jorge Gasteazoro
28-Jul-2004, 20:41
Hey Kirk, check out the thread on this forum about the View Camera forum. He seems to have time there.

In any case, DJ is an experienced photographer who has done a lot of testing. I am sure details like using the blue channel, picking the same targets to determine CI etc do not have to be spelled out for him. But I think you missed my point, even without a step tablet included in the negative, if you have two negatives of the same studio subject, then if they were developed to the same CI they should have similar DRs. If you pick the same spot on each of the negatives then some inference can be made. I am not saying it is perfect, but barring a step tablet exposed at the same time of the negative, it would be very hard to determine CI from just the negative.

If the question is to determine what developer produces the better stain for VC paper, then I would agree with you, but it seems that is a different question than what was discussed in the article. In short, S makes qualifications as better shadows, better contrast, etc, etc. He did not specify by saying "for printing with VC paper." This, I think is an entirely different question.

In the end, as I said, we are spinning our wheels here, looks like he is not up to the challenge.

sanking
29-Jul-2004, 09:15
Kirk wrote:

"That's sentence sounds pretty straight-forward and simple, but I think it is really just too simplistic. While I think it would be really interesting if Mr. Simmons were willing to allow a 3rd party to do some testing, I think that testing would be for naught unless there is a strictly defined set of conditions, guidelines, and goals for these tests and that they are described before any testing is done."

It may sound simplistic to you but the parameters are not all that complicated, though clearly different methods would be required for VC and graded papers. I could tell you a lot from evaluation of the negatives but it would not be based on densitometer readings since there is no absolute correlation of effective printing density range with VC and graded silver papers with densitometer readings, regardless of what color you use.

In any event this has become a mute point. Steve Simmons has made it clear that he will not be sending the negatives to anyone for this type of evaluation and since I am unable to control that decision there is nothing left to talk about. That being the case the questions that have been raised about the methodology of his testing procedures, and whether that methodology is adequate to justify the conclusions he reached and presented as fact, are left unanswered.

However, I very much doubt that we have seen the end of this discussion. There are many people out there with the technical competence to carry out methodologically sound testing of these developers and placing such an article in print or in an on-line photography journal would not be at all difficult.