Correction curves for hand sensitized contact printing processes normally look like inverted S-shapes in Photoshop, meaning they tend to flatten image contrast. As an exercise we tried to build a correction curve for standard RC silver paper (Kodak Polymax RC II). In the final print the tone range is clearly better with the correction curve, but we need to print also some “real world” pictures later to see if we need some further adjustments.

An example of how the correction looks after plotting the curve for Polymax II RC paper, using the Epson R1800 to print the negative. The test image looks very flat after correction, but the curve definitely improves tone separation in the contact print.

We also tried to build correction curves for MACO Black Magic liquid silver emulsion, but resulting from roughness of the paper, it was hard to measure the test print accurately with a scanner. And a different story is the trouble with coating any paper evenly with the emulsion, thereÂ’s a lot to learn about that. WeÂ’ll be returning to this topic laterÂ…

Two quick tests with MACO liquid emulsion. They are slightly overexposed, but you can see that the emulsion is quite contrasty (although it’s VC (variable contrast), and we used the lowest grade (#0) filtration). The left test was exposed on a single coated, and the right one on a double coated paper. The paper (Arches Aquarelle) was too textured for this test – it is hard to find even areas of tones for density readings.