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#11
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Pyro Developers Question.
On 8/11/2010 9:52 AM Thor Lancelot Simon spake thus:
In article , Darkroom User wrote: IanG;886420 Wrote: PYROCAT HD GIVES FINER GRAIN, BETTER SHARPNESS AND MORE TONALITY THAN D76, ALTHOUGH ORIGINALLY DESIGNED FOR LF NEGATIVES IT'S ALSO USED FOR 35MM &120 NEGATIVES. If it gives finer grain as well as better sharpness than D76, then it must be good. It also gives world peace and free beer. You can be sure it is excellent. My sentiments toward pyro as well. Not worth messing with, unless one is part of the more-exotic-than-thou brigade. -- The fashion in killing has an insouciant, flirty style this spring, with the flaunting of well-defined muscle, wrapped in flags. - Comment from an article on Antiwar.com (http://antiwar.com) |
#12
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Quote:
Please help me to learn, rather than post replies that come across as being sarcastic. I really do want to try to understand what is good darkroom practice, such as choosing the right processes and materials. I have many questions that I want to post here on photobanter. |
#13
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Jobo atl3
On 8/12/2010 12:15 AM Darkroom User spake thus:
David Nebenzahl;886934 Wrote: IanG;886420 Wrote: PYROCAT HD GIVES FINER GRAIN, BETTER SHARPNESS AND MORE TONALITY THAN D76, ALTHOUGH ORIGINALLY DESIGNED FOR LF NEGATIVES IT'S ALSO USED FOR 35MM &120 NEGATIVES.- If it gives finer grain as well as better sharpness than D76, then it must be good. IT ALSO GIVES WORLD PEACE AND FREE BEER. YOU CAN BE SURE IT IS EXCELLENT. My sentiments toward pyro as well. Not worth messing with, unless one is part of the more-exotic-than-thou brigade.[/i][/color] I am new to the darkroom and my questions concerning pyro are genuine. I had read on various sites about pyro developers including WD2D, PMK and Pyrocat-HD. If these developers offer no advantage over standards like D76, ID11 or XTol, then I will choose one of those instead. Please help me to learn, rather than post replies that come across as being sarcastic. I really do want to try to understand what is good darkroom practice, such as choosing the right processes and materials. I have many questions that I want to post here on photobanter.[/i][/color] I was being sarcastic, but I do take your concerns seriously. My serious answer to your queries about pyro developers is really "don't bother". It's not worth the hassle. You can get wonderful results using any of an array of readily-available conventional developers. So unless you insist on doing something peculiar, boutique-y and idiosyncratic, stick with D-76/ID-11, Microdol-X, Xtol, etc. By the way, just curious: what's with the strange quoting style you used (putting previously-quoted material in ALL CAPS, with non-functional "tags", like [/color])? That in itself is kinda like using pyro. I'm just saying ... -- The fashion in killing has an insouciant, flirty style this spring, with the flaunting of well-defined muscle, wrapped in flags. - Comment from an article on Antiwar.com (http://antiwar.com) |
#14
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Quote:
and those "tags" come up when I reply, although I do highlight certain quotes in bold type. By posting through this site, it helps to prevent receiving spam emails, although I am not sure if I am getting to read all of the replies to the threads. Thank you for your reasonable reply to stick with regular developers. I was curious to know why some people use pyro developers instead of normal non staining developers and what they perceive their advantages to be. I am here to learn from the more experienced photographers and darkroom users. :-) |
#15
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Jobo atl3
On 8/13/2010 1:18 AM Darkroom User spake thus:
I am posting through the Photo-Banter site: www.photobanter.com and those "tags" come up when I reply, although I do highlight certain quotes in bold type. By posting through this site, it helps to prevent receiving spam emails, although I am not sure if I am getting to read all of the replies to the threads. OK, you're forgiven: it's not your fault. The software you're using to post (Photobanter's forum software) is brain-damaged, at least where quoting text is concerned. Most of us here access Usenet (that's where these threads reside) the conventional way, using a mail client (aka "newsreader"), which shows the newsgroup the way [insert name of deity here] intended. You might try it yourself sometime. Actually more direct than going through a web site. And it's very easy to post without receiving spam: just do like me and use a phony "handle". Zero spam. -- The fashion in killing has an insouciant, flirty style this spring, with the flaunting of well-defined muscle, wrapped in flags. - Comment from an article on Antiwar.com (http://antiwar.com) |
#16
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Pyro Developers Question.
"Lew" wrote in message ... Isn't there also the claim that, as development & tanning progress in highlight areas, the emulsion physically compresses (as a result of the tanning) thereby holding less developer? ie there is even more moderation of highlight densities than there is via the mechanism of developer exhaustion alone. I haven't tested this extensively, but my limited experience leads me to believe that, on a very sunny day, with the sun overhead, plus areas of deep shadow, using iso 200 - 400 films, I did obtain easy to print negatives with plenty of highlight detail. I have never seen this suggested and doubt very much if it happens. Developer penetrates by diffusion from the surface. The "hardness" of the gelatin has little to do with it. AFAIK, there is no such action due to differential hardening. There is a differential imagewise shrinkage of the emulsion but it probably happens as the emulsion dries. One result of this is an acutance effect due to a difference of index of refraction along the demarcation of high and low density areas. It also produces a distortion of the image on a very small scale but enough so that tanning developers are undesirable for photo metrology purposes. -- -- Richard Knoppow Los Angeles, CA, USA |
#17
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Jobo atl3
"Darkroom User" wrote in message news David Nebenzahl;886934 Wrote: IanG;886420 Wrote: - PYROCAT HD GIVES FINER GRAIN, BETTER SHARPNESS AND MORE TONALITY THAN D76, ALTHOUGH ORIGINALLY DESIGNED FOR LF NEGATIVES IT'S ALSO USED FOR 35MM &120 NEGATIVES.- If it gives finer grain as well as better sharpness than D76, then it must be good. IT ALSO GIVES WORLD PEACE AND FREE BEER. YOU CAN BE SURE IT IS EXCELLENT. My sentiments toward pyro as well. Not worth messing with, unless one is part of the more-exotic-than-thou brigade. -- I am new to the darkroom and my questions concerning pyro are genuine. I[/i][/color] had read on various sites about pyro developers including WD2D, PMK and Pyrocat-HD. If these developers offer no advantage over standards like D76, ID11 or XTol, then I will choose one of those instead. Please help me to learn, rather than post replies that come across as being sarcastic. I really do want to try to understand what is good darkroom practice, such as choosing the right processes and materials. I have many questions that I want to post here on photobanter. -- Darkroom User[/i][/color] I think it is always interesting to experiment and learn. There is a definite effect of highlight compression when using a staining developer with variable contrast printing materials. Its quite measureable but may not be worth doing or may not be desirable for all images. The newer pyro formulas, like PMK are attempts to overcome some of the faults of the classical formulas, mostly that they tended to be grainy and somewhat unpredictable. The grain comes mainly from being active, most of these formulas use sodium carbonate or some equivalent as accelerators. They were necessary for the films which were contemporary with the developer. they work with newer films, especially when diluted more than the original instructions indicate. Formulas like the late ABC Pyro as published by Kodak, Ansco, and others, is fairly long lived in stock solutions and has relatively constant activity. Kodak D-7 is a Pyro-Metol formula with somewhat longer life in a tank or tray than ABC. There are a lot of variations. In my list are some special formulas including Kodak's version intended to maximize the stain image. Note that some users of PMK or Rolo Pyro suggest an after-bath in the developer to maximize the stain. What that does is to produce an overall stain, which is _not_ desirable rather than the imagewise stain which is what you want. A properly developed pyro negative should have little or no stain in the clear portions but a noticable yellow, greenish, or brownish stain following the image. The tanning is visible as a relief image on the dry film when held so that light reflects from the emulsion surface. Tanning developers were highly developed for use in producing the relief images used in the Kodak Dye Transfer process and Flexichrome process, each of which made use of the tanning to make parts of the emulsion more resistant to being removed by hot water. When "developed" by rinsing in the water the remaining emulsion followed the iamge exactly and could be used for absorbing dyes either for direct use (Flexichrome) or for transfer to a support paper in a process similar to lithography. An earlier version of the dye transfer process, called the Eastman Wash-Off Relief process used a different method of differential hardening, namely a bichromate process similar to that used for Carbon/Carbro. If you are interested in these old processes do a Google search for "alternative processes". Most are still practiced and can produce beatiful results. However, I suggest for someone starting out to make life simpler by using well-established packaged materials. Once you get control of the overall process of development and printing you can try experimenting with mix your own chemistry. Most of it is not difficult to do. There are NO magic developers but some have definite personalities which can make them interesting. Pyro is of historical importance, it was the first organic reducing agent to be discovered. I would not discourage anyone from trying it out but work with something more modern first. At this time probably the closest thing to an "optimum" developer is Kodak Xtol. Next choice is D-76, which is close to optimum for nearly anything and is perfectly reliable. After having used a lot of print developers I have gone back to plain old Dektol. The published formula D-72 is about the same stuff. Ilford makes an equivalent. Ilford Bromophen is a Dektol type developer that uses Phenidone in place of Metol. It is better for you if you are sensitive to Metol, which some people are and tends to give more neutral colored images with some materials. It is perfectly satisfactory. There are about a zillion print developer formulas that go to show simply how imprecise one can be in formulating:-) There is not much difference from one to another. As far as warm vs cold tone, that is mostly a property of the emulsion. While it is influenced by the developer its mainly established by the paper. Developers can have some influence on toning but that is often related to the amount of bromide in them or other variations that can be had by varying around a standard formula. One of the biggest differences between B&W and color photography is the lack of standardization in B&W. Color processing is very tighly specified and controlled and, while some variation is possible, the range of variation within which satisfactory color can be obtained are fairly limited. -- Richard Knoppow Los Angeles, CA, USA |
#18
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Unfortunately, Apple-Mail cannot be used for Newsgroups. I have edited out the color tags this time. :-)
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#19
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I like Kodak D-76, as I can buy it cheaper than ID-11 at the moment from Ag-Photographic in the UK for just £0.99 a litre of stock. The main advantage I can see for Xtol over D-76 is with replenishment. As I use D-76 1+1, I am happy to keep using it, although I have tried Xtol. Like wise with B&W papers, the character is mostly due to the emulsion itself rather than the developer types, although they can help in a subtle way. Again, a standard paper developer like Dektol, Bromophen, PQ-Universal, Multigrade or Adox WA liquid (formerly Agfa Neutol WA) would be good choices for regular use, although there are many others worthy of consideration. They are too close to each other in performance IMHO to worry about. |
#20
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Jobo atl3
In article ,
Darkroom User wrote: Unfortunately, Apple-Mail cannot be used for Newsgroups. I have edited out the color tags this time. :-) But you top-posted, which is every bit as rude. Stop doing that. Your new material should go between and below what you quote; never above it. -- Thor Lancelot Simon "All of my opinions are consistent, but I cannot present them all at once." -Jean-Jacques Rousseau, On The Social Contract |
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