[pure-silver] Re: Contrast paper developer
----- Original Message ----- From: "Ibrahim Pamuk" <ibrahim.pamuk@xxxxxxxxxxxxx> 
To: <pure-silver@xxxxxxxxxxxxx>
Sent: Monday, August 20, 2007 12:37 PM
Subject: [pure-silver] Re: Contrast paper developer
Your are right. It is also true that my negative quite grainy when I complaint about contast. They are a little over exposed infared negatives. I plan to go back to my old condenser enlarger. 

regards


Ibrahim Pamuk
Although the contrast is affected by the grain the difference between a fine grain and coarse grain silver negative should not be very much. There is a very large difference in Callier effect between the dye image of a color negative of transparency and a silver image but the differences between various types of silver is not a lot. One can assume about one paper grade difference between a diffusion and condenser printer for these. Also, even if one of the enlargers has a tungsten-halogen lamp and the other a plain tungsten lamp the difference in color temperature (assuming there is one) should not be enough to throw off the grades given by printing filters or color head filters by very much. In fact, the surface texture of the paper should make a bigger difference. The contrast and Dmax are reduced by matt surfaces so the actual contrast and density range produced by the filters will vary with the surface on any kind of paper. The rated values are usually for glossy paper. In any case, the point I want to make is that the very low contrast you have been getting is likely from something other than the type of light source in the enlarger. Other than lithographic developers there is very little difference in contast from one developer to another. The so-called "soft" developers are, for the most part, just slower to reach Dmax than "normal" developers. Some emulsions are more variable than others but the effect of the developer on paper is seldom even as much as one paper grade. It is often stated that condenser enlargers bring up blemishes more than diffusion enlargers. This is to some extent true but, if one is enlarging the same negative, the somewhat lower paper contrast required for the condenser enlarger will tend to suppress the blemishes so it all comes out about the same. Another thought: The settings for color head filters for variable contrast paper are only approximate. They must be the right settings for the particular brand of head and paper. Most variable contast paper comes with recommended settings on its data sheet. Usually the range of contrast is less for the color head than for individual filters but the spacings should be correct within that range. Usually only the highest and lowest contrast values are not available with the color head, the middle ranges are OK. 

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Richard Knoppow
Los Angeles, CA, USA
dickburk@xxxxxxxxxxxxx 
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