Photoshop masks should be the only choice you make when looking for a way to hide unwanted pixels. Never use the Eraser tool unless you are 150% positive you will never ever need those pixels again!
If you are just now coming upon this masking mini-series, check out Masking Basics and Layer Masks.
Most of masking is practice. There are a few tools that will make it easier, though.
I’ve discussed two different tablets, the Intuos3 and the Graphire4, that I have used personally. I prefer the Intuos3 tablet for every reason from more control to the feel of the pen and tablet. I highly recommend a tablet for graphics work. It makes masking, among other things, much much easier. It also provides a large degree of control and variety you simply can’t have with the mouse.
Specifically for masking purposes, you can control the stroke thickness and opacity on the fly by means of the pressure that you exert on the pen; lightly touch the tip to the tablet for less opacity and a thinner stroke, or press down hard for more opacity and a thicker stroke. You can turn these options on and off with the Brush palette (F5 or access it via the quick tabs in the top right hand corner of the Photoshop window).
Using Other Tools
As mentioned before, there is a wide variety of tools you can use with Layer Masks.
Dodge use Dodge to make light areas lighter and harden edges. Remember you can change the affected area (Range) by going to the context sensitive toolbar. Generally you want to affect the Highlights with Dodge.
Burn use Burn to make the dark areas darker and harden edges. Can also adjust Range (usually change to Shadows)
Blur soften edges and blend transitional areas.
Lasso, Marquee, Magic Wand tools can be used to create selections and then hit Alt/Opt + Delete or Ctrl/Cmd + Delete to fill with Foreground or Background color respectively.
Color Range is under Select> Color Range and is another way to select areas, this time using—you guessed it!—colors. With this tool, you’ll get an eyedropper when the cursor is over your image (you can also use the little preview if it’s set to Selection). Click on the colors you want to include in the selection (change to + or – eyedropper to add or subtract). You can also change the Selection Preview at the bottom to get an idea of what you are selecting in the whole image.
To get a smoother fill around the edges when you make a selection, while in a selection tool (lasso, marquee, magic wand), right click and choose Feather from the context sensitive menu and feather the selection .5 px. Then fill with foreground or background colors.
Gradient Tool is a great way to smoothly blend in or out an image. Use it in a mask as you normally would, only it’s grayscale.
And while you can use other art tools such as Clone Stamp and Smudge, there really isn’t much of a point to those because the images are strictly greyscale.
Channels for Precise Masks
It’s also important to be familiar with Channels, because they can help you mask out trickier objects like fur and trees.
If you go to your Channels Palette (usually a tab under the Layers Palette) you can click through the various channels of color. Find the channel that offers the most contrast between background and foreground. Copy that channel by dragging it onto the New Channel icon (looks like New Layer). Then, with the copied channel selected, go to Image>Adjustments and see which adjustment will increase the contrast while maintaining the edge of the object most effectively. Many times Brightness/Contrast will work, but you may want to test Curves and Levels as well. Remember that these adjustments are not editable once applied, unlike Adjustment Layers (which are editable, but not available in Channels).
You can also use the paint brush, dodge, burn, blur and other art tools on these Channels, though the result is only in greyscale. Once the channel has a good amount of contrast between object and background, Ctrl/Cmd + A to select the whole canvas and copy (Ctrl/Cmd + C). Click on the RGB composite channel to resume the full color of the document and click on the Layers tab to go back to the Layers Palette. Select your image layer and apply a Layer Mask to it. Alt/Opt + Click the Layer Mask thumbnail on the layer and then paste (Ctrl/Cmd + V). You can adjust the mask some more if you need to from here, keeping in mind that black hides and white reveals. You can invert the mask by hitting Ctrl/Cmd + I.
Constantly Switch Between Mask and Image
To make truly superb masks, you’ll need to keep checking your actual mask, not just seeing the normal image without its background.
To switch between the image view and the mask, Alt/Opt + click on the Layer Mask thumbnail (see image). Now you’ll see a black and white version of the mask. There are several things to look for here:
- Make sure areas that should be solid black (hidden) or solid white (revealed) are. Look for stray bits that didn’t get painted properly that you might not otherwise see in the image view.
- Fill in areas even outside where you know the image is to make absolutely certain nothing shows through that you don’t want.
For excellent Photoshop masks, there are 6 to remember:
- Black hides, white reveals
- Match the pixel quality of the brush to the quality of the edge of your object
- Switch between the image view and the mask view often to make sure it is being painted properly
- Get a Wacom!
- Hide every bit in the mask that doesn’t need to be revealed, even if it extends beyond the image area
There are two more important parts of masking still to cover. Quick Masks and Vector Masks. Have you ever heard of Quick Mask mode in Photoshop? Do you know what it is? Stay tuned to find out! Subscribe to Creative Curio via RSS or email. Vector Masks will be coming next week!
Photoshop Masking Series So Far
- Mastering Photoshop Masks: The Basics
- Mastering Photoshop Masks: Layer Masks
- Mastering Photoshop Masks: Expert Techniques (current post)
- Mastering Photoshop Masks: Quick Masks
- Mastering Photoshop Masks: Vector Masks
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