If a section of a mask isn’t quite correct, try using the Dodge or Burn tool in the mask to subtly adjust the edge (by lightening or darkening the grayscale values within the transitional area). In this example, the original mask is too soft and as a result, we can see a green halo around the edge of the leaf.
Looking at the original mask, we can see that the edge of the mask needs to be reduced in width as well as shifted towards the edge of the leaf. Note: This is also known as “choking” the mask. Moving in the other direction would be “spreading” the mask.
Using the Burn tool on the mask’s edge, darkens the values in the transitional areas of the mask, narrowing the transitional area and moving the mask in towards the leaf. (I realize that the change is subtle in this illustration, but notice how the edge of the mask in the illustration below appears sharper than in the illustration above.)
As a result of choking the mask, the green halo is removed from around the edge of the leaf.
“Join Julieanne Kost as she walks you through her creative thought process and explains how she transforms concepts and raw images into entirely new works of art using Adobe Photoshop. Discover how to select the images you need to create a whole that is greater than the sum of its parts. Master the tools used in compositing, including adjustment layers, masking, blending, and Smart Objects, so that the technology doesn’t get in the way of expressing your creative vision. Learn how to adjust scale and perspective and manipulate texture and focus to help viewers temporarily suspend their disbelief long enough to enter your world.”
What makes a good composite?
Refining your story
Composing using the basic principles of design
Customizing your Photoshop workspace
Preparing elements from your source images
Adjusting color, tone, balance, and perspective
Mastering the Pen tool
Unifying with texture, focus, leading lines, and structure
When painting with the Adjustment Brush in the Develop Module in Lightroom, tap the “O” key to Show/Hide Mask Overlay. Add the Shift key to cycle the mask overlay colors (red, green and white). Displaying the mask overlay can make it much easier to see areas the areas that are included/excluded from the adjustment in order to make refinements to the mask.
One of the ways that Photoshop can help blend multiple images together is through using the “Blend If” sliders in the Blending Options of the Layer Styles dialog. In this example I want to blend the clouds from the first image into the sky of the rock image.
With the Cloud image selected on the Layers panel, I choose layer > Layer Style > Blending Options (or, you can use the fx icon at the bottom of the Layers panel and choose Blending Options…).
In the Layer Styles dialog, I moved the black slider for the Underlying Layer to the right to hide the dark foreground values of the cloud image. In order to create a smooth transition, Option + (Mac) | Alt + (Win) click and drag the black triangle to split it into two. The values to the left of the split triangle will be completely transparent the values between the split triangle will transition from transparent to opaque, and the values to the right of the second split triangle will be fully opaque.
It’s OK if the rock in the foreground is semi transparent at this point – you want to focus on the “transitional areas” – where the new sky (the clouds) will meet the ocean and the top of the rocks.
To bring back the solid rocks in the foreground, I made a copy of the rock layer and moved it above the new sky (the clouds) layer in the Layers panel. Then, I added a layer mask and painted with black to hide the drab sky and reveal the clouds below, while keeping the rocks solid.
Because this example has a fairly straightforward horizon to mask, you might feel that I’m making this process or technique overly complicated. However, the Blend if sliders can be tremendously useful when masking detailed objects such as a tree against a sky. Notice that you can even change the Blend If options to blend individual color channels.
When working with Layer Masks, the Properties panel can be used to non-destructively soften the edge of the mask enabling it to be re-edited at a later time. This can be very useful if the size of the original file or even layer needs to be changed in the editing process.
To add a non-destructive feather, select the desired layer mask on the Layers panel. Then, on the Properties panel, adjust the Feather slider as needed. Although this feature was in Photoshop CS5 (via the Masks panel), in Photoshop CS6 the Feather values support decimal places.
Note: in Photoshop CS6, the Marquee, and Lasso tool’s feather values (in the Options bar), support decimal places as well.
When adding a mask to a layer in Photoshop, instead of guessing at the size of a feather that should be applied (because we know that the feather amount will vary depending on the resolution of the image and the desired softness of the edge that is being feathered), use the non-destructive Feather option on the Properties panel. To access the mask properties, click on the mask icon on the Properties Panel. Now, you can add a feather to soften an edge yet, if the image is resized or other adjustments need to be made at a later time, the feather can be appropriately adjusted.
And while you’re in the Properties panel, and the focus is on the mask, be sure to check out the non-destructive Density slider to reduce the opacity (density) of the mask.
When working on intricately composited, multi layered documents, I often find it useful to check each of the layer masks before finalizing the image. To do this, Option (Mac) / Alt (Win) -click on the mask thumbnail in the Layers panel to display it. With the mask visible, check to see if there are any unwanted awkward transitional areas that might not have been visible in the complex composite (a sharp edge from a selection or gradient for example).
• “Q” will toggle between Quick Mask and Normal Mode.
• Double click the Quick Mask icon on the tool panel to view Quick Mask Options.
• Command (Mac) / Control (Win) + 2 to view the Quick Mask, yet edit the composite image. Note: You can view the Channels panel to see what’s happening under the hood – notice how Command (Mac) / Control (Win) + 2 targets the RGB image instead of Quick Mask and that Command (Mac) / Control (Win) + 6 will target the Quick Mask).