Moiré is the pattern of interference that occurs when one fine pattern is overlaid on another—like when a fine check in a piece of clothing is rendered via a sensor tightly packed full of pixels. It produces what amounts to rippling highlights and shadows and even rainbow colors as the patterns don’t quite line up right, creating visual interference. In practice, it can be subtle and barely noticeable or it might be terribly distracting. In either case,9 it’s good to know how to get rid of it. I used to use a series of steps requiring multiple tools in Photoshop. Now I just turn to one single tool in Lightroom.
With the offending image selected in Lightroom, open the Develop module and zoom in close to fill the screen with the moiré pattern. At the top of the right-hand sidebar, just below the Histogram, you’ll see a selection of controls: the Crop Overlay, the Spot Removal tool, the Red Eye Correction tool, the Graduated Filter, the Radial Filter and the Adjustment Brush. It’s these last two—in particular the last one, the Adjustment Brush—that offer straightforward and simplified moiré removal.
Click on the Adjustment Brush and then down near the bottom of the list of sliders you’ll see one for Moiré. The more you drag the slider to the right, into positive values, the stronger the reduction of the pattern will be. Then, simply adjust the brush size (not far below the moiré slider in the panel) and be sure to use a feathered edge. You can reduce the flow, too, if you’d like a more subtle approach—but I don’t when I’m fighting moiré, so I leave it maxed at 100.
Next, simply click and drag to paint the fix onto the moiré pattern in your picture. You can make multiple passes, as well as readjusting the size and flow of the brush, as well as the intensity of the repair with the Moiré slider. After completing the repair, you can always re-click on the small gray circle that’s now visible on the image in Lightroom when you have the Adjustment Brush tool active in order to adjust a previous attempt at the moiré reduction, making it stronger or less intense.
I mentioned earlier that you can also use the Radial Filter to similar effect. It’s the same sort of application of the tool, but it can only be applied in round or oblong shapes rather than the freehand painting that can be done with the Adjustment Brush—which is why the Adjustment Brush should be your first stop for a straightforward Lightroom fix to even the nastiest moiré interference.