Print Adjustment for Shadows


Today’s Question: Do I understand it correctly that you’d move the Levels adjustment slider from 0 to 15 in your Print Target example before pressing “Print” [to compensate for a lack of shadow detail in the print]?

Tim’s Quick Answer: Yes, if testing has demonstrated that my prints are not rendering full shadow detail all the way down to a full black value, I would apply an adjustment using Levels before printing my photos. It is important to note that this would relate to the “Output Levels” adjustment, not the black point adjustment found directly below the histogram in the Levels dialog.

More Detail: The issue here is that in many cases a print will not reflect the full level of shadow detail as actually exists in the image file. Instead, that shadow gets “blocked up”, similar to the way shadow detail gets clipped in an exposure that is too dark. You can compensate for this issue by essentially brightening the value of black, causing all neighboring tonal values to be brightened up accordingly.

The key is to determine the optimal adjustment to apply. This can be done using a print target image that contains a series of dark shades toward black (and a series of bright shades toward white). You can print the test image using your normal printing workflow, and then evaluate the results under a very bright light source.

When you determine which tonal value is the first where you can see a visible difference between the two values, the darker of those two represents your target black point for the print. So in Photoshop you can apply a Levels adjustment just before printing, setting the Output Levels value for black to the value you determined from the test print.

In Lightroom you could use the Tone Curve to apply the same basic adjustment. Be sure you are in the Point Curve mode for the Tone Curve adjustment, rather than the Parametric option. In other words, make sure you don’t see the sliders for Highlights, Lights, Darks, and Shadows below the curve, clicking the button at the bottom-right of the Tone Curve section if you need to switch modes. Then drag the black end point of the curve (the bottom-left end of the diagonal line) upward. The adjustment value will be shown as a percentage in the top-left of the curve area while you are dragging, so you’ll need to convert the tonal level value to a percentage by dividing the value by 256 first.

You can obtain a print target image I use for evaluating black and white levels in my prints by following this link: