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#1
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Light source for Pyro negs
I'm not yet experienced with Pyro development, but I'm considering to give it a try. My questions concern the enlarger lamp for pringing pyro negatives. I read frequently that a cold light head is best for pyro negatives (presumably due to the yellowish stain on the neg), but I have a standard tungsten halogen lamp in my only enlarger, an Omega D2 with Super Chromega color head. I hope to use VC paper (Forte and Kodak). If the spectrum really must be close to that of a cold light head, is there a filtration offset that can be dialled into on the enlarger's color head to closely simulate the spectrum of a cold light lamp? Or, with regard to pringint pyro negs, is the spectral difference between cold light and tungsten halogen too small to be concerned about? Regards, Szabo ----== Posted via Newsfeeds.Com - Unlimited-Uncensored-Secure Usenet News==---- http://www.newsfeeds.com The #1 Newsgroup Service in the World! 120,000+ Newsgroups ----= East and West-Coast Server Farms - Total Privacy via Encryption =---- |
#2
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In article ,
Szaboht wrote: I'm not yet experienced with Pyro development, but I'm considering to give it a try. My questions concern the enlarger lamp for pringing pyro negatives. I read frequently that a cold light head is best for pyro negatives (presumably due to the yellowish stain on the neg), but I have a standard tungsten halogen lamp in my only enlarger, an Omega D2 with Super Chromega color head. I hope to use VC paper (Forte and Kodak). The Chromega is perfectly fine. If the spectrum really must be close to that of a cold light head, is there a filtration offset that can be dialled into on the enlarger's color head to closely simulate the spectrum of a cold light lamp? Or, with regard to pringint pyro negs, is the spectral difference between cold light and tungsten halogen too small to be concerned about? You can use the standard Poly Contrast filter values. Or seamlessly adjust by varying the Yellow and or Magenta. 7y + 21m = Grade 2 etc. -- 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 |
#3
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In article ,
Szaboht wrote: I'm not yet experienced with Pyro development, but I'm considering to give it a try. My questions concern the enlarger lamp for pringing pyro negatives. I read frequently that a cold light head is best for pyro negatives (presumably due to the yellowish stain on the neg), but I have a standard tungsten halogen lamp in my only enlarger, an Omega D2 with Super Chromega color head. I hope to use VC paper (Forte and Kodak). The Chromega is perfectly fine. If the spectrum really must be close to that of a cold light head, is there a filtration offset that can be dialled into on the enlarger's color head to closely simulate the spectrum of a cold light lamp? Or, with regard to pringint pyro negs, is the spectral difference between cold light and tungsten halogen too small to be concerned about? You can use the standard Poly Contrast filter values. Or seamlessly adjust by varying the Yellow and or Magenta. 7y + 21m = Grade 2 etc. -- 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 |
#4
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Szaboht wrote in message . ..
I'm not yet experienced with Pyro development, but I'm considering to give it a try. My questions concern the enlarger lamp for pringing pyro negatives. I read frequently that a cold light head is best for pyro negatives (presumably due to the yellowish stain on the neg), but I have a standard tungsten halogen lamp in my only enlarger, an Omega D2 with Super Chromega color head. I hope to use VC paper (Forte and Kodak). If the spectrum really must be close to that of a cold light head, is there a filtration offset that can be dialled into on the enlarger's color head to closely simulate the spectrum of a cold light lamp? Or, with regard to pringint pyro negs, is the spectral difference between cold light and tungsten halogen too small to be concerned about? Regards, Szabo Yes I think the spectral difference of the light source would be a fairly minor consideration, unless hairsplitting the science is more interesting that making pictures to you. The stain of a pyro neg acts as a low contrast filter, for the highlights with VC paper. I don't think it has any effect on graded paper. The standard tungsten light source is contrastier than a cold light, so your move to pyro would definitly smooth out the tonal range. I think you'll love the look. My landscapes have taken on a far smoother, more realistic and atmospheric quality. Enjoy. |
#5
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Szaboht wrote in message . ..
I'm not yet experienced with Pyro development, but I'm considering to give it a try. My questions concern the enlarger lamp for pringing pyro negatives. I read frequently that a cold light head is best for pyro negatives (presumably due to the yellowish stain on the neg), but I have a standard tungsten halogen lamp in my only enlarger, an Omega D2 with Super Chromega color head. I hope to use VC paper (Forte and Kodak). If the spectrum really must be close to that of a cold light head, is there a filtration offset that can be dialled into on the enlarger's color head to closely simulate the spectrum of a cold light lamp? Or, with regard to pringint pyro negs, is the spectral difference between cold light and tungsten halogen too small to be concerned about? Regards, Szabo Yes I think the spectral difference of the light source would be a fairly minor consideration, unless hairsplitting the science is more interesting that making pictures to you. The stain of a pyro neg acts as a low contrast filter, for the highlights with VC paper. I don't think it has any effect on graded paper. The standard tungsten light source is contrastier than a cold light, so your move to pyro would definitly smooth out the tonal range. I think you'll love the look. My landscapes have taken on a far smoother, more realistic and atmospheric quality. Enjoy. |
#6
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"Szaboht" wrote in message ... I'm not yet experienced with Pyro development, but I'm considering to give it a try. My questions concern the enlarger lamp for pringing pyro negatives. I read frequently that a cold light head is best for pyro negatives (presumably due to the yellowish stain on the neg), but I have a standard tungsten halogen lamp in my only enlarger, an Omega D2 with Super Chromega color head. I hope to use VC paper (Forte and Kodak). If the spectrum really must be close to that of a cold light head, is there a filtration offset that can be dialled into on the enlarger's color head to closely simulate the spectrum of a cold light lamp? Or, with regard to pringint pyro negs, is the spectral difference between cold light and tungsten halogen too small to be concerned about? Regards, Szabo Pyro developers produce a stain image that acts to intensify the silver image. The printing contrast is higher than the visual contrast. The stain image is yellowish and blocks blue light. Its effect depends mostly on the spectral sensitivity of the paper. Most cold light heads are quite blue, although there are some that approximately duplicate tungsten light for use with variable contrast filters. I think the idea that the cold light head is preferable comes from this. However, if the paper sees only blue light the spectral output of the printing light doesn't matter. Now, when variable contrast paper is used with pyro negatives there is some tendency for the stain image to act as a contrast reducing filter for the highlights. This may or may not be desirable since low contast highlights make prints look flat. The spectral distribution of the printing light will make some difference if VC paper is used the lack of green light tending to _increase_ contrast. Note that the low contrast filters for variable contrast paper are yellow while the high contrast filters are magenta. Yellow blocks blue light, magenta blocks green. All this is getting away from the point. If you print on graded paper the spectral content of the printing light will make little difference because the paper has a relatively limited spectral sensitivity which is centered in the range where the Pyro stain image is most effective. Blue cold light heads screw up variable contrast filtering anyway. Color heads and condenser heads are quite suitable for Pyro negatives. Just don't expect magic. I suspect many who rave about Pyro are getting better negatives because they are paying more attention to controlling all the variables. -- --- Richard Knoppow Los Angeles, CA, USA |
#7
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"Szaboht" wrote in message ... I'm not yet experienced with Pyro development, but I'm considering to give it a try. My questions concern the enlarger lamp for pringing pyro negatives. I read frequently that a cold light head is best for pyro negatives (presumably due to the yellowish stain on the neg), but I have a standard tungsten halogen lamp in my only enlarger, an Omega D2 with Super Chromega color head. I hope to use VC paper (Forte and Kodak). If the spectrum really must be close to that of a cold light head, is there a filtration offset that can be dialled into on the enlarger's color head to closely simulate the spectrum of a cold light lamp? Or, with regard to pringint pyro negs, is the spectral difference between cold light and tungsten halogen too small to be concerned about? Regards, Szabo Pyro developers produce a stain image that acts to intensify the silver image. The printing contrast is higher than the visual contrast. The stain image is yellowish and blocks blue light. Its effect depends mostly on the spectral sensitivity of the paper. Most cold light heads are quite blue, although there are some that approximately duplicate tungsten light for use with variable contrast filters. I think the idea that the cold light head is preferable comes from this. However, if the paper sees only blue light the spectral output of the printing light doesn't matter. Now, when variable contrast paper is used with pyro negatives there is some tendency for the stain image to act as a contrast reducing filter for the highlights. This may or may not be desirable since low contast highlights make prints look flat. The spectral distribution of the printing light will make some difference if VC paper is used the lack of green light tending to _increase_ contrast. Note that the low contrast filters for variable contrast paper are yellow while the high contrast filters are magenta. Yellow blocks blue light, magenta blocks green. All this is getting away from the point. If you print on graded paper the spectral content of the printing light will make little difference because the paper has a relatively limited spectral sensitivity which is centered in the range where the Pyro stain image is most effective. Blue cold light heads screw up variable contrast filtering anyway. Color heads and condenser heads are quite suitable for Pyro negatives. Just don't expect magic. I suspect many who rave about Pyro are getting better negatives because they are paying more attention to controlling all the variables. -- --- Richard Knoppow Los Angeles, CA, USA |
#8
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Szaboht wrote in message . ..
I'm not yet experienced with Pyro development, but I'm considering to give it a try. My questions concern the enlarger lamp for pringing pyro negatives. I read frequently that a cold light head is best for pyro negatives (presumably due to the yellowish stain on the neg), but I have a standard tungsten halogen lamp in my only enlarger, an Omega D2 with Super Chromega color head. I hope to use VC paper (Forte and Kodak). If the spectrum really must be close to that of a cold light head, is there a filtration offset that can be dialled into on the enlarger's color head to closely simulate the spectrum of a cold light lamp? Or, with regard to pringint pyro negs, is the spectral difference between cold light and tungsten halogen too small to be concerned about? Regards, Szabo ----== Posted via Newsfeeds.Com - Unlimited-Uncensored-Secure Usenet News==---- http://www.newsfeeds.com The #1 Newsgroup Service in the World! 120,000+ Newsgroups ----= East and West-Coast Server Farms - Total Privacy via Encryption =---- 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. The stain is without grain and has a nicer gradation of tone than silver has, but again, only for graded (blue-sensitive) paper. A negative correctly developed in pyro has a rather 'thin' silver base which the stain supplements. If the stain were to be removed, the silver density of a properly-developed pyro negative would be seen as too flat and thin. It's supposed to be that way, because the stain assists in providing enough PRINTING density to give a good print. |
#9
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"Uranium Committee" wrote in message om... 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. |
#10
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"Uranium Committee" wrote in message om... 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. |
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