When you make a selection in Zoner Photo Studio, you’re really creating a mask. You don’t have to know this to do basic work with selections, but learning to understand masking gives you better insight and control. To learn more about masking, read on.

If you work with photo editing, then you may have heard the terms “masking” and “mask.” After all, at its core, every advanced graphics editor works in basically the same way. But what is a mask?

Where Will You Encounter Masks in Zoner Photo Studio?

But how about a simpler definition? Selections are areas that you set off using the Editor’s selection tools (all the tools surrounded with a dashed line, plus the Magic Wand). You use them to make your edits affect only a picture that you’ve chosen—that you’ve selected. Need to mildly desaturate part of a photo? Need to brighten eyes, add light to a face, or darken a sky? In all of these situations you can make use of selections, and thus masks.

To set if, and how, the mask is shown, use the Mask Display control. It contains several options: Do Not Show, Normal, Inverted, and Mask Only. The factory setting is Do Not Show.

How Masks Work

When you make an edit in Zoner Photo Studio, and you haven’t applied it yet, the edit floats on a temporary layer above the background layer that contains your current picture. That layer can cover the whole picture, or just a selected part. A selection is that “selected part” and mask is the inverse of it.

When you click “Apply” for an edit, the program creates a “mix” of the picture before the edit with the picture after the edit, since your “before” version is on the background layer, and your “after” version is on the floating temporary layer. How the blended version looks depends on the opacity of the temporary layer, and on your blending Mode. Selections and masks affect the opacity.

The selection—the mask—defines in what places that floating layer is opaque, in what places it’s transparent, and in what places it’s in-between. In other words: in what places any edit you make will be used, will be unused, or will be used at less than full strength. You can also think of the mask as a black-and-gray-and-white picture that sets where, and how much, an edit will actually be used.

The biggest difference between viewing a selection and viewing the mask that defines it is that, unlike viewing the selection, viewing the mask lets you see what places are selected at less than full strength.

We go into more detail about selections in a separate article; here we’ll be focusing on Zoner Photo Studio’s controls for making the mask really stand out visually, that is, for really highlighting that “black-and-gray-and-white picture,” so you know exactly where and how much your edits will have an effect.

What You’re Seeing When You See the Mask

We’ll be illustrating how masking works on the example of this picture here. For our illustration, we’ll first be working with the Selection Brush:

Here I’ve switched the mask display from the usual “Do Not Show” setting over to “Normal.” The area with the red haze over it is what’s being “masked away” by the mask. The area that’s covered by this haze less, or not at all, is what isn’t being masked away—in other words, it’s the selection. Our edits will affect this area.

Smooth Transitions

Being able to see the mask becomes important when you have a selection that blends smoothly into the unselected part of your picture. But how do you make that kind of a selection? The main way is via the Blur setting offered by each selection tool.

• No Blur means a sharp transition.
• A high Blur means a gradual transition from “fully selected” to “fully unselected”.

The picture below shows an example of what the mask looks like after you’ve used a selection tool (the Elliptical Selection tool) with a high Blur.

After setting up this mask here, we might very gently brighten the face. If we do, then the brightening will blend smoothly, and not jarringly, into the rest of the picture, because the high Blur is making the selection “fade out” slowly into the mask. Since the mask is basically the inverse of the selection, in our screenshot, you can see this fading-out of the selection as a fading-in of the mask at the edge of the selection.

The picture below shows how a high Blur affects the next selection tool we’ll be illustrating—the Selection Brush.

Mask Only

What if seeing the mask itself is more important to us at the moment than seeing the picture that’s being masked? That’s when the Mask Only mode becomes useful.

The screenshot above shows how the Mask Only display looks after we’ve done the kind of work with the Selection Brush that would often come just before some real-world retouching. Take a look at the Brush’s settings (in the right column). We’ve carefully avoided a sharp, highly visible transition between the selected and unselected parts of the picture. The Density and Blur settings we’ve used help with this.

We’ve mentioned Blur above—what about Density, though?

We’ve gradually painted on our selection with this conservatively configured Selection Brush. In the screenshot, you can clearly see how the selection under the eyes, above the eyes, and around the mouth gradually fades into the mask.

(If you’ve got a drawing tablet, we recommend using it for this kind of work, as it will let you work very precisely.)

Masks for All Seasons

You can benefit from the different mask displays during a variety of edits—retouching, brightening hair and giving it highlights, brightening eyes, emphasizing light in the face, darkening the sky, etc. But we’ll leave the details of that for another article.

For now just remember that work with the different mask displays gives you better insight into your selections—especially when you’re using a high Blur to make your edits blend in smoothly.