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steve simmons
18-Jun-2004, 07:29
I have run to tests with these developers. One using 35mm FP4+ and one using 4x5 Tri-X and FP4+. The first article was in the June/July 04 CameraArts and the second will be in the July/Aug 04 View Camera. The result seem consistent in both tests

PMK creates more stain,more elevated high values, a slightly sharper print and just a little more grain. I also seem to get a little more film speed from PMK.

One alwys has to calibrate their film and fim developer to te paper they are using. This is true with a staining developer and a non-staining developer. The comments about PMK not working with variable contrst paper are innaccurate. If you are not getting enough contrast with a staining developer then increase your developing time just as you would with a non-staining developer.

steve simmons

Dean Cookson
18-Jun-2004, 08:42
Steve, Do your tests include densitometer readings or just test prints? In either case, did you have the opportunity to test UV measurements or UV sensitive processes in addition to visible light?

steve simmons
18-Jun-2004, 08:56
Steve, Do your tests include densitometer readings or just test prints? In either case, did you have the opportunity to test UV measurements or UV sensitive processes in addition to visible light?

????????????????????

>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

My final product is the finished silver print. I test using the mnimum time for max black process. It never fails. This may insult the sensitometrists in the group but I end up with very similar densities and wonderful looking prints which is what photography, at least for me, is all about.

I have not tested but I do not know why the results would be any different for pl/pd pints.

steve simmons

Dean Cookson
18-Jun-2004, 09:01
No commentary here on which was is better, just wondering what was in the test.

I'm curious about the pt/pd vs ag prints question because some of the sensitometry data I've seen seems to show that HD stain is more UV opaque than PMK stain is for equal values of visible light opacity. A side by side comparison of using PMK and HD to make dual-purpose negatives would be very interesting.

Larry Gebhardt
18-Jun-2004, 10:34
Steve, did you also test a conventional developer like HC-110 or D-76 as a control variable? If you could post hi res scans it would be interesting.

Jorge Gasteazoro
18-Jun-2004, 11:32
If you could post hi res scans it would be interesting



Larry, you wanna see pictures, you have to buy the magazine.....:-)

Larry Gebhardt
18-Jun-2004, 12:01
Jorge, funny how that works....

I will recieve my copy of View Camera in the mail. But even then some hi-res scans on the web would be nice. I had the opertunity to see Bruce Barlow's prints from a few issues ago, and the reproduction in the magazine was not suitable for making any determinations of quality. I suspect the same will be true of these tests - but I could be wrong - we will see.

steve simmons
18-Jun-2004, 13:20
The differences will be obvious in the magazine

steve simmons

Jay DeFehr
18-Jun-2004, 17:15
Steve, given that the only measuring device in use in these tests is your eyeballs, how did you determine that "PMK creates more stain"? And what kind of stain is PMK creating more of; general stain or proportional stain? Also, what do you mean by "more elevated high values"? Do you mean that there is more density in the high values? As for " a slightly sharper print and just a little more grain", that is a very subjective statement, and in fact, without any kind of variable controls or measuring devices, your entire comparison is meaningless to anyone but yourself. Why bother publishing it? You could just as effectively published a simple statement declaring your preference for PMK.

Jorge Gasteazoro
18-Jun-2004, 17:23
You could just as effectively published a simple statement declaring your preference for PMK



LOL.......

Bruce Watson
18-Jun-2004, 21:02
I'm with you Jay.

I would love to see more actual scientific research on developers in general, and staining developers specifically. But that means objective testing, and experiements that can be recreated and re-run by other people who can (and do) get the same results. Scientific method and all that.

Yet another testimony of undying love for PMK is, well, meaningless, as Jay says. More importantly, it doesn't pursuade. If you want me to try pyro, you have to do more than tell me how great you think it is. Show me the data.

Donald Miller
18-Jun-2004, 21:50
"I'm with you Jay. I would love to see more actual scientific research on developers in general, and staining developers specifically. But that means objective testing, and experiements that can be recreated and re-run by other people who can (and do) get the same results. Scientific method and all that.

Yet another testimony of undying love for PMK is, well, meaningless, as Jay says. More importantly, it doesn't pursuade. If you want me to try pyro, you have to do more than tell me how great you think it is. Show me the data."

It has become increasingly more apparent to me that Mr. Steve Simmons abhors scientific basis for any of the bold statements that he makes. I wonder why that is...but I suspect that I know...I think that it can best be summed up with the statement "Don't confuse me with the facts, my mind is made up". I think that it is sad when a person takes such an arrogant stance and determines for themselves that they are an "expert". Perhaps Mr. Simmons had best quit reading his own "press".

Steve Simmons sent me an email last week soliciting an article for publication. After hearing of Jorge G's experience, I have far more important matters to occupy my time then engage in the wasted effort of writing for such a unprofessional publication. I hesitate to have my name affiliated in any manner with him or his publications.

I have found that these types of matters eventually even out. Perhaps for Mr. Simmons this will occur when his publications are no longer in demand at the level that he desires.

I have seen people shoot themselves in the foot before. But they normally learn more quickly, then Mr. Simmons, has that this is a self defeating behavior.

steve simmons
18-Jun-2004, 21:51
I sugest looking at the results in the magazines.That will tell the real story.

have all of the negatives on file and will share them with ayone who comes to the ofice and I will have them at all future trade shows and conferences we attend.

Photo Plus in NYC this Fall SPE and Photolucida in Portland next spring the next View Camera conference.

The proof is is the pudding as they say. I will show my pudding

stev simmons

Dean Cookson
18-Jun-2004, 22:12
Steve, I'm sure you have a fine pudding.

That having been said...

If you have the opportunity to do a follow-up to your tests comparing the various pyro developers and their suitability for making dual purpose (sliver and platinum printing) negatives, I'd be interested in it.

Yours in custard,

Jorge Gasteazoro
18-Jun-2004, 22:39
Yet another testimony of undying love for PMK is, well, meaningless, as Jay says. More importantly, it doesn't pursuade. If you want me to try pyro, you have to do more than tell me how great you think it is. Show me the data.



Hogarth, here is where I see the problem. VC, regardless of what is printed in the cover as "The Journal of LF photography" is not geared to publish a rigorous test. You get little more than 2 or 3 pages, in this is difficult to describe the full methodology and have it published. I tried that as best as I could, but in the end my efforts fell short. Simmons thought my charts were "too" hard to understand. Perhaps I should have included a little explanation on the charts, but I thought anybody who publishes a journal of photography would be able to figure them out. In the end, if you are expecting an article with h+d curves, full description of the constants and how all the variables were adjusted, etc, etc....you better not hold your breath.

steve simmons
18-Jun-2004, 23:57
In the end, if you are expecting an article with h+d curves, full description of the constants and how all the variables were adjusted, etc, etc....you better not hold your breath.>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

I was Jorge and did not get it. No one I showed your charts to understood what you were dong and these pople all had 10+ years in the black and white and alt phot industry.

Perhaps Iwill have to do this myself. Not a bad idea.

steve immons

steve simmons
18-Jun-2004, 23:58
If you have the opportunity to do a follow-up to your tests comparing the various pyro developers and their suitability for making dual purpose (sliver and platinum printing) negatives, I'd be interested in it.

Yours in custard, >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

This is a good suggestion and we will followup on it.

thanks

steve simmons

Jorge Gasteazoro
19-Jun-2004, 06:44
I was Jorge and did not get it. No one I showed your charts to understood what you were dong and these pople all had 10+ years in the black and white and alt phot industry.



Perhaps Iwill have to do this myself. Not a bad idea.



LOL...how convenient that all the people you show them to cannot understand them, yet there are 100's of thousands if not millions of people that do. I will post examples of the charts on APUG`s technical gallery and you can all judge for yourself how hard they are.



As to do it yourself, perhaps you should have done this before you published your very suspect results.

Jorge Gasteazoro
19-Jun-2004, 07:03
Ok, the example of a BTZS chart is up now here (http://www.apug.org/gallery/showphoto.php/photo/413/size/big/password//sort/1/cat/502) you can judge for yourself how hard they are.

Armin Seeholzer
19-Jun-2004, 17:16
Why not test the best developer? XTOL was the best developer in a sientific test in a lab mag in german about 5 years ago! It is like religions some belive that and others this!

sanking
19-Jun-2004, 20:10
One of the reasons I would have been very reluctant to do a comparison article between PMK and Pyrocat-HD for publication is because my previous comparisons have shown the results to be so similar (in both sharpness and grain) that I don't believe it would be possible to show any differences unless you made huge prints. I have made comparison 20X24 prints from 4X5 negatives using PMK and Pyrocat-HD and there was absolutely no difference in the prints in either grain, sharpness or tonality. I have also made comparison prints from small sections of PMK and Pyrocat-HD at 25X magnification and observed little or no difference. Sometimes the PMK print looks sharper, at other times the Pyrocat-HD print looks sharper. I concluded from this that the small differences in T-dimension with sheet film or the difference in how flat the film is held with roll film cameras is of much greater importance in sharpness than any difference in sharpness in the developers.

The essential thing, however, for this type of comparison of sharpness, is to develop both negatives so that they have exactly the same effective printing density range. With pyro stained negatives there is virtually no way to determine the exact time of development to give the exact density range needed without using either a densitometer or step wedges, and the step wedges are much less expensive and more accurate.

I strongly suspect that if there are is any significant difference in sharpness between the prints he made from PMK and Pyrocat-HD negatives the reason is that he did not match the contrast and most likely the PMK negatives had greater printing contrast. I am certain that Steve believes that he did match the contrast and if he happens to join this conversation will say that he did. But if he really found differences in sharpness so great that they will show in a magazine, especially in View Camera where the reproductions are not all that good, something was really wrong with his testing procedures. I have corresponded with literally hundreds of photographers who have used Pyrocat-HD after first using PMK and if there was a difference in sharpness of as much as Steve describes I am fairly confident they would have immediately seen and recognized it.

BTW, for those interested in the differences in printing with UV processes with PMK and Pyrocat-HD should look at my article on pyro developers at http://unblinkingeye.com/Articles/PCat/pcat.html As far as I know this is the only information either in print or on a web site that accurately describes the differences and the reasons therefor.

sanking
19-Jun-2004, 20:40
Just for the record I would be happy to post scans of my own comparisons of PMK and Pyrocat-HD but the resolution of my Epson 4870 scanner is well below the resolution limit of both PMK and Pyrocat-HD, which in both cases is well over 100lpm with low and medium speed films such as Efke 25 and 100, Tmax 100 and Ilford FP4+.

If anyone would volunteer to scan the comparision negatives with a very high resolution scanner I would be happy to send you the negatives. In turn I am fairly certain that we could place the results in my article at http://unblinkingeye.com/Articles/PCat/pcat.html, with credit.