Oct. 1999
President's
Message
DCC Photo Course
Portrait of ...
Article: Variable Contrast Papers
Variable Contrast Enlarging Papers
- Bill Talarowski
Variable contrast black and white enlarging
papers offer several advantages over graded papers. The most obvious is
that you don’t have to stock or refrigerate several boxes of different
grades of paper. With one box of variable contrast paper and a set of
variable contrast filters (or a dichroic color head) you will be able
to handle any contrast need you might encounter, from grade 0 to grade
5.
A second advantage is that you can access in-between grades of contrast by using the ˝ filters or the appropriate settings on your color head. This allows you to use precisely the contrast grade that is ideal for a given negative—something you can not do with graded papers which come only in full grade steps of contrast.
A third advantage of VC papers is that you can print part of the image through one filter and the rest through another. If, for example, you have a landscape with a low contrast foreground and a high contrast sky, you can use the 3 or 4 filter on the foreground and a 0 or 1 filter on the sky.
You might wonder how all these grades of contrast are packed into one paper. Each sheet of paper contains two light sensitive emulsions: a high contrast emulsion that is sensitive to only blue light, and a low contrast emulsion sensitive only to green light. High contrast is achieved by printing through a filter that transmits blue light and green light. Low contrast is produced by doing just the opposite. Intermediate grades of contrast are produced by printing through filters that transmit light of both colors, thus exposing both emulsions to some degree of two colors.
Magenta and yellow (the opposite colors of green and blue) are used as they pass more light which makes seeing the negative image on the easel easier.
Lately, I have concentrated on using two papers. One is Agfa MCP-310 RC, which gives me sparkling whites and rich blacks. This paper is excellent for exhibition prints, but due to its punch, is harder to print and needs a full scale negative. The other paper is Kodak Polymax II. It has a slightly warmer black and yields prints of excellent quality. One of its nice properties is being able to make an image from very thin negatives. With both papers I use Ethol, single mix LPD paper developer, which has a very long working life when kept in a full, air tight bottle.