Kodalith on a Computer - Brief Article

PSA Journal, August, 2000 by Nick Muskovac

With electronic imaging on the computer, it is possible to simulate a Kodalith process using a digital image taken from a 35mm slide.

First, pick out a good subject. I usually use a building or a structure with well-defined lines. Most of the time I try to include a sky. Here is how to do it:

I will describe the process using Photoshop 5.5 since this is my favorite Electronic Imaging Program. In order to get the image into the computer, you can send slides to Kodak to have them put it on a Photo CD or if you own a slide scanner, you can do it yourself. I use the Nikon LS1000 and scan slides directly into Photoshop. If you are going to make a print in the range of 8 x 10 or 8 x 12, the slide should be scanned at a file size between 10 and 18 Mb. This is also more than adequate for slide reproduction from a film recorder.

For my example I have used a roller coaster image from Busch Gardens. (See original photo in Figure 1.)

The first step is to crop the image to fit your final output. This is where we decide what ratio print or slide that we will be making. I use the Photoshop rectangular marquee tool with "Constrained Aspect Ratio" and adjust the option as follows:

Use a 3:2 ratio for a 35mm slide or the print ratio of your choice, i.e. 8 x 10 or 8 x 12 print. In my example, I used a 3:2 ratio for a 35mm slide.

Note: these numbers represent a ratio and not dimensions of your print.

When the marquee is in place; select Image "Crop" to complete the operation. Next make a duplicate copy of the background layer. This layer will be used to make the Kodalith. We now apply Image>Adjust>Threshold. The Threshold is then inverted so that the sky will be black. I prefer a dark sky. See Figure 2 for the Threshold layer image.

The next step is to set the layer mode for the Threshold to "Darken." Then we use the move tool and move the Threshold layer down and to the right about 2 pixels. You can experiment with this setting as it depends on the file size and the effect that you like.

At this point I usually select the background layer and increase the saturation level to give it more punch. You should save this file as a Photoshop extension to keep the layers, and then flatten all layers and save the final image as a TIF format.

To finish the photo, a narrow red border was applied. Figure 3 (left page) shows the final image.

So, get one of your favorite subjects, and give it a try.

Have fun.