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#21
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"PATRICK GAINER" wrote in message ... Uranium Committee wrote: "Jim Phelps" wrote in message ... "Uranium Committee" wrote in message e.com... The 'benefit' of a stained negative is the stain, which takes the place of silver density for papers that are sensitive only to blue. The stain is yellowish-green, and since these stains block blue light, they are seen as extra density by blue-sensitive paper. Variable contrast paper DOES see 'green', and so the stain DOES NOT act as density for VC papers. Use and GRADED paper to get the 'benefits' of pyro. The light source does not matter so much. DO NOT use VC paper, because it defeats the whole purpose of pyro. This information is completely wrong. No, it's correct! FACT: the stain is yellowish-green FACT: the stain TRANSMITS yellowish-green and STOPS blue light FACT: graded paper is insensitive to green or yellow light FACT: VC paper is sensitive to green light CONCLUSION: the stain ADDS density as far as graded paper is concerned, and DOES NOT add density as far as VC paper is concerned. In addition, the green light that the stain allows through softens the contrast in the most-heavily-exposed areas, precisely the opposite effect that occurs when graded paper is used. Attempting to use VC filtration to raise the contrast simply ignores the stain again, and you end up fighting against the stain. It is quite obvious that you have not tried it, and that you have not reasoned out the answer that you did not try. The yellow stain is a variable density stain. You can bleach out the silver image and leave a yellow IMAGE, not a filter layer. This yellow image can be printed on VC paper by use of sufficient blue filtering. I have done it, and several years ago demonstrated it in an article in Photo Techniques titled "More Pyrotechnics" . Certainly, the yellow image is of quite low contrast when printed on unfiltered VC paper, but it is there. The yellow part of an unbleached pyro negative DOES increase the contrast on VC paper, though not as much as on graded paper. If you do the following experiment, you will see the fallacy in your reasoning. Develop any negative in any non-staining developer to a lower than normal contrast index. Make a straight print without filtration on VC paper. Now bleach the negative in a rehalogenating solution such as is used in sepia toning, and redevelop it in a pyro staining developer. Make a straight print from this negative without filtration. Now make another print using magenta filtration or a #3 or #4 printing filter. Report to us the results if you dare. Its possible to bleach out either the stain or the silver image. The stain can be removed by using a permanganate type bleach. The stain image, as pointed out Patrick, acts as a proportional intensifier. Its density in relation to the silver density varies with the type of developer and the type of film. The ratio of densities can also be measured by making separate readings though the red and blue status filters of a color densitometer. The red filter will measure the silver image density along, the blue will measure both. The important thing is that there is no change in film characteristic, i.e., the _shape_ of the exposure vs: density curve from Pyro, only a change in its _effective_ overall slope. You could also prove this by printing on panchromatic paper trough red and blue filters. In the case of variable contrast paper it is possible that the yellow stain image causes a reduction of contrast as the density increases. I have never seen actual densitometric measurements of this so I can't say whether it is a reall or only a claimed effect. To be blunt I think Pyro is something of a fad. Pyro was the most used developer into the early 20th century but fell out of use when other, and better, developers became available. -- --- Richard Knoppow Los Angeles, CA, USA |
#22
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"PATRICK GAINER" wrote in message ... Uranium Committee wrote: "Jim Phelps" wrote in message ... "Uranium Committee" wrote in message e.com... The 'benefit' of a stained negative is the stain, which takes the place of silver density for papers that are sensitive only to blue. The stain is yellowish-green, and since these stains block blue light, they are seen as extra density by blue-sensitive paper. Variable contrast paper DOES see 'green', and so the stain DOES NOT act as density for VC papers. Use and GRADED paper to get the 'benefits' of pyro. The light source does not matter so much. DO NOT use VC paper, because it defeats the whole purpose of pyro. This information is completely wrong. No, it's correct! FACT: the stain is yellowish-green FACT: the stain TRANSMITS yellowish-green and STOPS blue light FACT: graded paper is insensitive to green or yellow light FACT: VC paper is sensitive to green light CONCLUSION: the stain ADDS density as far as graded paper is concerned, and DOES NOT add density as far as VC paper is concerned. In addition, the green light that the stain allows through softens the contrast in the most-heavily-exposed areas, precisely the opposite effect that occurs when graded paper is used. Attempting to use VC filtration to raise the contrast simply ignores the stain again, and you end up fighting against the stain. It is quite obvious that you have not tried it, and that you have not reasoned out the answer that you did not try. The yellow stain is a variable density stain. You can bleach out the silver image and leave a yellow IMAGE, not a filter layer. This yellow image can be printed on VC paper by use of sufficient blue filtering. I have done it, and several years ago demonstrated it in an article in Photo Techniques titled "More Pyrotechnics" . Certainly, the yellow image is of quite low contrast when printed on unfiltered VC paper, but it is there. The yellow part of an unbleached pyro negative DOES increase the contrast on VC paper, though not as much as on graded paper. If you do the following experiment, you will see the fallacy in your reasoning. Develop any negative in any non-staining developer to a lower than normal contrast index. Make a straight print without filtration on VC paper. Now bleach the negative in a rehalogenating solution such as is used in sepia toning, and redevelop it in a pyro staining developer. Make a straight print from this negative without filtration. Now make another print using magenta filtration or a #3 or #4 printing filter. Report to us the results if you dare. Its possible to bleach out either the stain or the silver image. The stain can be removed by using a permanganate type bleach. The stain image, as pointed out Patrick, acts as a proportional intensifier. Its density in relation to the silver density varies with the type of developer and the type of film. The ratio of densities can also be measured by making separate readings though the red and blue status filters of a color densitometer. The red filter will measure the silver image density along, the blue will measure both. The important thing is that there is no change in film characteristic, i.e., the _shape_ of the exposure vs: density curve from Pyro, only a change in its _effective_ overall slope. You could also prove this by printing on panchromatic paper trough red and blue filters. In the case of variable contrast paper it is possible that the yellow stain image causes a reduction of contrast as the density increases. I have never seen actual densitometric measurements of this so I can't say whether it is a reall or only a claimed effect. To be blunt I think Pyro is something of a fad. Pyro was the most used developer into the early 20th century but fell out of use when other, and better, developers became available. -- --- Richard Knoppow Los Angeles, CA, USA |
#23
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In article ,
"Richard Knoppow" wrote: To be blunt I think Pyro is something of a fad. Pyro was the most used developer into the early 20th century but fell out of use when other, and better, developers became available. Well I am sure that could be among the unwashed masses. I've been using Pyro developers since the early 1990's maybe mid 1980's well before Gordon Hutchings published his book. There are also other photographers who have a much longer history than myself Michael A Smith, Steve Simmons probably a whole slue of others. I probably would have given up on Pyro had Gordon not devised the PMK formula, and had others not made other improvements in the Formula aka (Rollo PMK). The fade could be a result of f a reinsurgance of interest in the roots of photo, people's interest in Alt process as Pyro stained negatives have merits towards those applications. I personally became interested in Albumen printing and alt process as a result of my college history of photo course, I read the Keepers of Light and was some what intrigued by some of the old process. Around 1988 I did some basic experiments in creating salted prints paper negatives, it was a little before you heard so much of people doing such things. Its the fun side of photography so I doubt it will readily die out. -- LF Website @ http://members.verizon.net/~gregoryblank "To announce that there must be no criticism of the President, or that we are to stand by the President, right or wrong, is not only unpatriotic and servile, but is morally treasonable to the American public."--Theodore Roosevelt, May 7, 1918 |
#24
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In article ,
"Richard Knoppow" wrote: To be blunt I think Pyro is something of a fad. Pyro was the most used developer into the early 20th century but fell out of use when other, and better, developers became available. Well I am sure that could be among the unwashed masses. I've been using Pyro developers since the early 1990's maybe mid 1980's well before Gordon Hutchings published his book. There are also other photographers who have a much longer history than myself Michael A Smith, Steve Simmons probably a whole slue of others. I probably would have given up on Pyro had Gordon not devised the PMK formula, and had others not made other improvements in the Formula aka (Rollo PMK). The fade could be a result of f a reinsurgance of interest in the roots of photo, people's interest in Alt process as Pyro stained negatives have merits towards those applications. I personally became interested in Albumen printing and alt process as a result of my college history of photo course, I read the Keepers of Light and was some what intrigued by some of the old process. Around 1988 I did some basic experiments in creating salted prints paper negatives, it was a little before you heard so much of people doing such things. Its the fun side of photography so I doubt it will readily die out. -- LF Website @ http://members.verizon.net/~gregoryblank "To announce that there must be no criticism of the President, or that we are to stand by the President, right or wrong, is not only unpatriotic and servile, but is morally treasonable to the American public."--Theodore Roosevelt, May 7, 1918 |
#25
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Gregory W Blank wrote in message news:8Vkpd.10455$1B2.683@trnddc02...
In article , "Richard Knoppow" wrote: To be blunt I think Pyro is something of a fad. Pyro was the most used developer into the early 20th century but fell out of use when other, and better, developers became available. Well I am sure that could be among the unwashed masses. I've been using Pyro developers since the early 1990's maybe mid 1980's well before Gordon Hutchings published his book. There are also other photographers who have a much longer history than myself Michael A Smith, Steve Simmons probably a whole slue of others. I probably would have given up on Pyro had Gordon not devised the PMK formula, and had others not made other improvements in the Formula aka (Rollo PMK). The fade could be a result of f a reinsurgance of interest in the roots of photo, people's interest in Alt process as Pyro stained negatives have merits towards those applications. I personally became interested in Albumen printing and alt process as a result of my college history of photo course, I read the Keepers of Light and was some what intrigued by some of the old process. Around 1988 I did some basic experiments in creating salted prints paper negatives, it was a little before you heard so much of people doing such things. Its the fun side of photography so I doubt it will readily die out. Richard has often stated that pyro is probably a fad, or people are getting good effects because of an increased amount of attention paid. All I can say is after many years of regular developers, resulting in highly diluted developers to control landscape contrast, I tried pyro (cat) and was finally happy with the look of things. I could maintain alot of shadow detail, yet still have a nice atmospheric sky, even though the exposures usually favor the shadow. My skies would often white out with regular developers. Less dev. times and the scene goes flat and looks like a compensating developer or preflash was used. The powerful Ansel Adams look often settles for darker shadows, as the image made is more theatrical than I'm making. Weston too, has than drama. I'm more interested in how the eye sees the contrast, and really have to fight for longer tones. Although they both have many shots where it all comes together, I tend to think thats due to lighting conditions more than anything else. With my dev. time using pyrocat, I have found where I can get a long tonal range while still maintaining a perfect contrast. Never flat looking and IMO more natural looking than regular developers. If I want the punchier graphic look, I stick with D-76, but pyrocat definitly yeilds a unique and natural looking image. More like what the eye sees. 1:100 Rodinal, highly diluted HC-110, etc, will deaden into flatness if I reduce the development enough to hold the high areas the way the pyro does. I would say that because I give a full shadow exposure, even in contrasty light, my highs get way up there, so the stain allows good printability but is still a pleasing white. Detail without drabness. Ken Smith |
#26
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Gregory W Blank wrote in message news:8Vkpd.10455$1B2.683@trnddc02...
In article , "Richard Knoppow" wrote: To be blunt I think Pyro is something of a fad. Pyro was the most used developer into the early 20th century but fell out of use when other, and better, developers became available. Well I am sure that could be among the unwashed masses. I've been using Pyro developers since the early 1990's maybe mid 1980's well before Gordon Hutchings published his book. There are also other photographers who have a much longer history than myself Michael A Smith, Steve Simmons probably a whole slue of others. I probably would have given up on Pyro had Gordon not devised the PMK formula, and had others not made other improvements in the Formula aka (Rollo PMK). The fade could be a result of f a reinsurgance of interest in the roots of photo, people's interest in Alt process as Pyro stained negatives have merits towards those applications. I personally became interested in Albumen printing and alt process as a result of my college history of photo course, I read the Keepers of Light and was some what intrigued by some of the old process. Around 1988 I did some basic experiments in creating salted prints paper negatives, it was a little before you heard so much of people doing such things. Its the fun side of photography so I doubt it will readily die out. Richard has often stated that pyro is probably a fad, or people are getting good effects because of an increased amount of attention paid. All I can say is after many years of regular developers, resulting in highly diluted developers to control landscape contrast, I tried pyro (cat) and was finally happy with the look of things. I could maintain alot of shadow detail, yet still have a nice atmospheric sky, even though the exposures usually favor the shadow. My skies would often white out with regular developers. Less dev. times and the scene goes flat and looks like a compensating developer or preflash was used. The powerful Ansel Adams look often settles for darker shadows, as the image made is more theatrical than I'm making. Weston too, has than drama. I'm more interested in how the eye sees the contrast, and really have to fight for longer tones. Although they both have many shots where it all comes together, I tend to think thats due to lighting conditions more than anything else. With my dev. time using pyrocat, I have found where I can get a long tonal range while still maintaining a perfect contrast. Never flat looking and IMO more natural looking than regular developers. If I want the punchier graphic look, I stick with D-76, but pyrocat definitly yeilds a unique and natural looking image. More like what the eye sees. 1:100 Rodinal, highly diluted HC-110, etc, will deaden into flatness if I reduce the development enough to hold the high areas the way the pyro does. I would say that because I give a full shadow exposure, even in contrasty light, my highs get way up there, so the stain allows good printability but is still a pleasing white. Detail without drabness. Ken Smith |
#27
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Gregory W Blank wrote in message news:8Vkpd.10455$1B2.683@trnddc02...
In article , "Richard Knoppow" wrote: To be blunt I think Pyro is something of a fad. Pyro was the most used developer into the early 20th century but fell out of use when other, and better, developers became available. Well I am sure that could be among the unwashed masses. I've been using Pyro developers since the early 1990's maybe mid 1980's well before Gordon Hutchings published his book. There are also other photographers who have a much longer history than myself Michael A Smith, Steve Simmons probably a whole slue of others. I probably would have given up on Pyro had Gordon not devised the PMK formula, and had others not made other improvements in the Formula aka (Rollo PMK). The fade could be a result of f a reinsurgance of interest in the roots of photo, people's interest in Alt process as Pyro stained negatives have merits towards those applications. I personally became interested in Albumen printing and alt process as a result of my college history of photo course, I read the Keepers of Light and was some what intrigued by some of the old process. Around 1988 I did some basic experiments in creating salted prints paper negatives, it was a little before you heard so much of people doing such things. Its the fun side of photography so I doubt it will readily die out. Richard has often stated that pyro is probably a fad, or people are getting good effects because of an increased amount of attention paid. All I can say is after many years of regular developers, resulting in highly diluted developers to control landscape contrast, I tried pyro (cat) and was finally happy with the look of things. I could maintain alot of shadow detail, yet still have a nice atmospheric sky, even though the exposures usually favor the shadow. My skies would often white out with regular developers. Less dev. times and the scene goes flat and looks like a compensating developer or preflash was used. The powerful Ansel Adams look often settles for darker shadows, as the image made is more theatrical than I'm making. Weston too, has than drama. I'm more interested in how the eye sees the contrast, and really have to fight for longer tones. Although they both have many shots where it all comes together, I tend to think thats due to lighting conditions more than anything else. With my dev. time using pyrocat, I have found where I can get a long tonal range while still maintaining a perfect contrast. Never flat looking and IMO more natural looking than regular developers. If I want the punchier graphic look, I stick with D-76, but pyrocat definitly yeilds a unique and natural looking image. More like what the eye sees. 1:100 Rodinal, highly diluted HC-110, etc, will deaden into flatness if I reduce the development enough to hold the high areas the way the pyro does. I would say that because I give a full shadow exposure, even in contrasty light, my highs get way up there, so the stain allows good printability but is still a pleasing white. Detail without drabness. Ken Smith |
#28
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Richard Knoppow wrote:
"PATRICK GAINER" wrote in message ... Uranium Committee wrote: "Jim Phelps" wrote in message ... "Uranium Committee" wrote in message le.com... The 'benefit' of a stained negative is the stain, which takes the place of silver density for papers that are sensitive only to blue. The stain is yellowish-green, and since these stains block blue light, they are seen as extra density by blue-sensitive paper. Variable contrast paper DOES see 'green', and so the stain DOES NOT act as density for VC papers. Use and GRADED paper to get the 'benefits' of pyro. The light source does not matter so much. DO NOT use VC paper, because it defeats the whole purpose of pyro. This information is completely wrong. No, it's correct! FACT: the stain is yellowish-green FACT: the stain TRANSMITS yellowish-green and STOPS blue light FACT: graded paper is insensitive to green or yellow light FACT: VC paper is sensitive to green light CONCLUSION: the stain ADDS density as far as graded paper is concerned, and DOES NOT add density as far as VC paper is concerned. In addition, the green light that the stain allows through softens the contrast in the most-heavily-exposed areas, precisely the opposite effect that occurs when graded paper is used. Attempting to use VC filtration to raise the contrast simply ignores the stain again, and you end up fighting against the stain. It is quite obvious that you have not tried it, and that you have not reasoned out the answer that you did not try. The yellow stain is a variable density stain. You can bleach out the silver image and leave a yellow IMAGE, not a filter layer. This yellow image can be printed on VC paper by use of sufficient blue filtering. I have done it, and several years ago demonstrated it in an article in Photo Techniques titled "More Pyrotechnics" . Certainly, the yellow image is of quite low contrast when printed on unfiltered VC paper, but it is there. The yellow part of an unbleached pyro negative DOES increase the contrast on VC paper, though not as much as on graded paper. If you do the following experiment, you will see the fallacy in your reasoning. Develop any negative in any non-staining developer to a lower than normal contrast index. Make a straight print without filtration on VC paper. Now bleach the negative in a rehalogenating solution such as is used in sepia toning, and redevelop it in a pyro staining developer. Make a straight print from this negative without filtration. Now make another print using magenta filtration or a #3 or #4 printing filter. Report to us the results if you dare. Its possible to bleach out either the stain or the silver image. The stain can be removed by using a permanganate type bleach. The stain image, as pointed out Patrick, acts as a proportional intensifier. Its density in relation to the silver density varies with the type of developer and the type of film. The ratio of densities can also be measured by making separate readings though the red and blue status filters of a color densitometer. The red filter will measure the silver image density along, the blue will measure both. The important thing is that there is no change in film characteristic, i.e., the _shape_ of the exposure vs: density curve from Pyro, only a change in its _effective_ overall slope. You could also prove this by printing on panchromatic paper trough red and blue filters. In the case of variable contrast paper it is possible that the yellow stain image causes a reduction of contrast as the density increases. I have never seen actual densitometric measurements of this so I can't say whether it is a reall or only a claimed effect. To be blunt I think Pyro is something of a fad. Pyro was the most used developer into the early 20th century but fell out of use when other, and better, developers became available. Pyro does have advantages for those who would like to be able to use the same negative for either printing-out processes that require high contrast but are only blue sensitive or printing with VC paper. There are also advantages claimed for wide range scenes that include clouds. I have been privileged to have a compilation of the papers of Hurter & Driffield who considered and experimented with inorganic developer and organic pyrogallol. They never made much of the staining by pyro, using enough sulfite to pretty well eliminate the stain. My point, with which I think you agree, is that the effect of the pyro stain when properly done is to increase the contrast even with VC paper, though not as much as with graded paper, and to present some experiments to demonstrate it. I do not use a lot of staining developer, but do occasionally use it as an intensifier to increase contrast of underveveloped negatives. I guarantee it works, and the process may be repeated. Each repetition restore the original silver density and adds to it a proportional stain. |
#29
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Richard Knoppow wrote:
"PATRICK GAINER" wrote in message ... Uranium Committee wrote: "Jim Phelps" wrote in message ... "Uranium Committee" wrote in message le.com... The 'benefit' of a stained negative is the stain, which takes the place of silver density for papers that are sensitive only to blue. The stain is yellowish-green, and since these stains block blue light, they are seen as extra density by blue-sensitive paper. Variable contrast paper DOES see 'green', and so the stain DOES NOT act as density for VC papers. Use and GRADED paper to get the 'benefits' of pyro. The light source does not matter so much. DO NOT use VC paper, because it defeats the whole purpose of pyro. This information is completely wrong. No, it's correct! FACT: the stain is yellowish-green FACT: the stain TRANSMITS yellowish-green and STOPS blue light FACT: graded paper is insensitive to green or yellow light FACT: VC paper is sensitive to green light CONCLUSION: the stain ADDS density as far as graded paper is concerned, and DOES NOT add density as far as VC paper is concerned. In addition, the green light that the stain allows through softens the contrast in the most-heavily-exposed areas, precisely the opposite effect that occurs when graded paper is used. Attempting to use VC filtration to raise the contrast simply ignores the stain again, and you end up fighting against the stain. It is quite obvious that you have not tried it, and that you have not reasoned out the answer that you did not try. The yellow stain is a variable density stain. You can bleach out the silver image and leave a yellow IMAGE, not a filter layer. This yellow image can be printed on VC paper by use of sufficient blue filtering. I have done it, and several years ago demonstrated it in an article in Photo Techniques titled "More Pyrotechnics" . Certainly, the yellow image is of quite low contrast when printed on unfiltered VC paper, but it is there. The yellow part of an unbleached pyro negative DOES increase the contrast on VC paper, though not as much as on graded paper. If you do the following experiment, you will see the fallacy in your reasoning. Develop any negative in any non-staining developer to a lower than normal contrast index. Make a straight print without filtration on VC paper. Now bleach the negative in a rehalogenating solution such as is used in sepia toning, and redevelop it in a pyro staining developer. Make a straight print from this negative without filtration. Now make another print using magenta filtration or a #3 or #4 printing filter. Report to us the results if you dare. Its possible to bleach out either the stain or the silver image. The stain can be removed by using a permanganate type bleach. The stain image, as pointed out Patrick, acts as a proportional intensifier. Its density in relation to the silver density varies with the type of developer and the type of film. The ratio of densities can also be measured by making separate readings though the red and blue status filters of a color densitometer. The red filter will measure the silver image density along, the blue will measure both. The important thing is that there is no change in film characteristic, i.e., the _shape_ of the exposure vs: density curve from Pyro, only a change in its _effective_ overall slope. You could also prove this by printing on panchromatic paper trough red and blue filters. In the case of variable contrast paper it is possible that the yellow stain image causes a reduction of contrast as the density increases. I have never seen actual densitometric measurements of this so I can't say whether it is a reall or only a claimed effect. To be blunt I think Pyro is something of a fad. Pyro was the most used developer into the early 20th century but fell out of use when other, and better, developers became available. Pyro does have advantages for those who would like to be able to use the same negative for either printing-out processes that require high contrast but are only blue sensitive or printing with VC paper. There are also advantages claimed for wide range scenes that include clouds. I have been privileged to have a compilation of the papers of Hurter & Driffield who considered and experimented with inorganic developer and organic pyrogallol. They never made much of the staining by pyro, using enough sulfite to pretty well eliminate the stain. My point, with which I think you agree, is that the effect of the pyro stain when properly done is to increase the contrast even with VC paper, though not as much as with graded paper, and to present some experiments to demonstrate it. I do not use a lot of staining developer, but do occasionally use it as an intensifier to increase contrast of underveveloped negatives. I guarantee it works, and the process may be repeated. Each repetition restore the original silver density and adds to it a proportional stain. |
#30
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Richard Knoppow wrote:
big snip To be blunt I think Pyro is something of a fad. Pyro was the most used developer into the early 20th century but fell out of use when other, and better, developers became available. True, but that was before PMK, which turned pyrogallol based developers into a reliable method of development. Our gratitude to Patrick Gainer for that. Francis A. Miniter |
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