Photoshop Layer Mask Concepts & Basics – Part 3


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The material in this blogpost comes from:

 My Photoshop book called  “Not Just Another Photoshop Book”

•  And, mSmall Group Workshop called “The Power of Layer Masks in Photoshop”




There is incredible power in being able to work on your image in Photoshop “globally” (the whole image), as well as “locally” (just part of your image).  Being able to localize your image adjustments is the digital post-processing equivalent of the legendary Ansel Adams’ & Fred Archers’ photographic Zone System –  see this post for more as it relates to Photoshop:


 This is Part 3 of what will be a multi-part series of blogposts on Layer Masks.  Each post will be short and sweet, and focused on just one aspect of Layer Masks – given in bite-size pieces, if you will.

•  As a refresher, Part 1 discusses the importance of why you need Layer Masks, Adjustment Layers, and much more:

•  Part 2 concerns the two Workspace Panels critical to working with Layer Masks – The Layers Panel & the Properties Panel:

•  For Part 4, see the link near the bottom  …



Part 3 – Layer Mask Strategies


There are two “strategies” used in creating and working with Layer Masks:





•  So, which “Strategy” should you use?


Strategy #1Best to use where the area in your image that you want to isolate is NOT sharply delineated in Brightness or Color …


Strategy #1 is analogous to “painting”, and works best with the Brush Tool (We’ll discuss Tools for making and shaping Selections in future posts):



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•  The snowy foreground & trees in Image “A” are too blue, while the rest of the image’s color hue looks fine.  Using Strategy #1, a Hue/Saturation Adjustment Layer is created to de-saturate the blue hue (we discussed Adjustment Layers extensively in Part 1).


•  In Image “B”, the Brush Tool is used to select the area to be changed (the foreground & trees).  At this point, nothing has changed in the image, because an adjustment hasn’t made yet  (de-saturate the blue).


•  After making the adjustment (de-saturate the blues in the foreground & trees), Image “B” shows the results, bringing the snow in the foreground to a more realistic neutral color.  You’ll notice that the rest of the image’s color cast isn’t changed.


Strategy #2Best to use where the area in your image that you want to isolate is sharply delineated in Brightness or Color …


Strategy #2 is analogous to “drawing”, and is most commonly used with the Magic Wand Tool, Quick Selection Tool , Lasso Tool,  & Object Selection Tool (We’ll discuss Tools for making & shaping Selections in future posts):


Click to Zoom In & Pan


•  The sky in Image “A” is too light and washed out, while the rest of the image’s brightness looks fine.


•  In Image “B”:  Using Strategy #2, the Magic Wand Tool is used to select the area to be changed.  The animated dashed line is called the Selection Border – however, it’s more commonly known in the Photoshop community as “Marching Ants”.


•  In Image “C”, after making the selection, a Levels Adjustment Layer is created, automatically “revealing” the area you’ve selected.  Then Levels is used to darken the sky.  You’ll notice that the rest of the image’s brightness hasn’t changed.




Layer Mask Basic Procedure, sequentially:


1)  A Layer Mask is shaped in conjunction with the Layer Mask Thumbnail, one of the five parts of an Adjustment Layer (See Part 1 for more).


2)  If you need to activate the Layer Mask, click in the Layer Mask Thumbnail and a thin line will highlight it to show that the Layer Mask is active.


3)  Activating your Layer Mask allows you to use the appropriate selection tools in your image (NOT in the Thumbnail) to “paint” or “draw” the areas that you want to hide and/or reveal.


4)  As you shape with Selection Tools (discussed in future posts), your results will not only show up in your image, but in the Layer Mask Thumbnail as Black and White.


Layer Mask Key Points:


Always rememberBlack “Hides” & White “Reveals” the effects of your Adjustment  …


 If you’d like to see your Layer Mask super-imposed over your image, hold down the “Alt” key (“Option” on a Mac), then click once with your left Mouse button in your Layer Mask Thumbnail.  To remove it, simply do the same thing again. Oh, and you can work on your super-imposed mask with selection tools, too – no need to go back to the image to continue shaping.


•  To completely fill your Layer Mask with Black (to hide) rather than the default of White (to reveal), click on the Layer Mask Thumbnail so it is active, use the speed key “Ctrl” + I (“Command+ I on a Mac) , or go to “Edit” -> “Fill” and choose “Black” from the “Contents” drop-down menu.




In the next Quick Tip in this series:  Layer Mask Concepts & Basics, Part 4 –  Selection Tools & Techniques – coming soon …


Don’t forget, the material in this blogpost is from one of my Small Group Workshops called “The Power of Layer Masks in Photoshop” they’re live, online & available nationwide:




•  AVAILABLE NATIONWIDE – for more on my free live & online Photoshop Meetups, click here:


•  More Photoshop videos at my YouTube Channel:


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•  By the way, this is all based on my Photoshop book designed for photographers, “Not just another Photoshop Book”, available exclusively on Amazon:


Questions? Please contact me – also, feel free to comment and forward this to your photography friends!


Thx again, and cheers,


John Watts 🙂



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