One of the most important tasks in creating a rich print is controlling the highlight and shadow detail. In my film days, I worried about Zone II and Zone VIII. When working with digital imagery we set white and black points with a similar goal. In the process I’m going to describe, I actually set two different points: one for a dark gray above black, and another for a light gray below white (yes, Zone II and Zone VIII again).
The process starts with printing an assessment target to determine the RGB values that produce these highlight and shadow values using your paper/printer combination. Figure 3 shows my current assessment target. It has boxes of RGB tonal values ranging from 0, 0, 0 to 34, 34, 34 for the shadows, and high- lights ranging from 255, 255, 255 to 221, 221, 221. Because I use a printer that can handle it, I created my test tar- get in 16-bit format.
Once you have created your test chart, bring it up in Photoshop. Select your paper for printing and input all of the characteristics and profile exactly for printing. In my case, I used the Canon imagePROGRAF Export plug- in for Photoshop because I use the iPF 6100 that allows me to import 16-bit files to the printer. This test is only accurate if you exactly duplicate the printing characteristics and input data you’ll use in your final print.