Adjustment layers started out in Photoshop as a way of altering the look of an image without actually changing its pixels. It was the start of non-destructive editing. Now, adjustment layers are everywhere, not just in Photoshop, and for me they are the key to successful image enhancements.
There’s a second factor, though – layer masks. Without layer masks, adjustment layers simply apply a blanket adjustment to the whole image. With masks, however, you can apply and combine carefully crafted local adjustments that can transform a picture.
We all have our own styles and likes, and I like dense, dramatic imagery, so apologies if there’s a bit of a theme developing in my tutorials! The point about adjustment layers and masks, though, is that you can adapt them to your own style, so hopefully this will prove useful even when you’re going for a very different look to mine.
How adjustment layers work
Adjustment layers simply change the appearance of the layer below without actually affecting it directly. You can look at them as a series of processing ‘instructions’ that are applied virtually to the on-screen image, but aren’t actually applied for real until you export a new, processed image.
In Photoshop they’re used for single adjustments like curves, levels, hue, saturation and lightness and so on. In other programs, they are much more sophisticated. For this example I’m using Alien Skin Exposure X4, where you can use all of its adjustment tools and effects on any adjustment layer. You can do the same in Capture One, for example.
The other point about adjustment layers is that you can ‘stack’ them. With regular image layers, the top layer obscures the layer(s) below, but with adjustment layers, the adjustments and effects you apply are combined. The image I’ve created here has four adjustment layers.
Layer masks
With any adjustment layer you can use a ‘mask’ to hide its effect in certain parts of the picture. In my example I’ve used the gradient mask tool in Exposure X4 in different areas to ‘localise’ the adjustment I’ve made. Most programs now offer gradient masks tools and they are a simple and effective way to subtly blend in an adjustment. They’re most often used for darkening bright skies, but they can be used in other areas too.
As well as gradient masks, many programs offer radial masks for masking a circular or elliptical region of the image, and for irregular shapes and more precise masking you can use freehand brush tools. Some programs offer auto-masking options which can follow the edges of objects automatically.
I do just want to say something about selections, masking and feathering. Many programs (and photographers) concentrate on extremely precise masking techniques for creating cutouts, adding new backgrounds or building photo-montages. It’s difficult to get these pixel-perfect and even if you do the results can look rather obviously ‘layered’. I prefer a smoother, more ‘blended’ masking technique. In its own way it can look just as obvious as pixel-perfect masking, but it nevertheless looks more ‘photographic’. It’s also a lot easier to do!
How this image was created
01: Base image
This is the photo with all the adjustment layers disabled so that you can see it in its original state. I knew I would probably make adjustments later so I exposed this shot to keep the detail in the cloudy sky. You can bring back much more shadow detail in RAW files than highlight detail.
02: Sky darkening
The first adjustment was to make the sky darker still, so for this I used Exposure X4’s gradient mask tool, angled slightly to follow the line of the rocks in the background. Graduated filter effects need careful position and, usually, a wide ‘blending’ zone. A simple downward Tone Curve adjustment has given the sky more depth and contrast.
03: Foreground lightening
I wanted the foreground to be a little lighter, so this needed another adjustment layer, this time with the gradient mask rotated so that the foreground was adjusted and not the sky. An upward Tone Curve adjustments makes the foreground lighter and enhances its contrast.
04: Base darkening
Very often I think if you’re using a strong graduated filter effect on a sky you need to add a counterbalancing effect right at the base of the picture, so that’s what I’ve done here, using a third adjustment layer, gradient mask and Tone Curve adjustment.
05: Adding a preset effect
That’s fine as a basic set of colour adjustments, but I can also add one of Exposure X4’s preset effects over the top of all these adjustments by creating a fifth adjustment layer above all the rest. I can now apply any of the preset effects to this layer with affecting my previous adjustments. I like the ‘Fade all, leaving strong reds’ preset for this image, and I’ve added a vignette effect to this layer too for a bit more drama.
‘Soft’ vs ‘hard’ masking
All the adjustments I’ve made here use ‘soft’ masks. They’re quicker to apply and their effect is, to my eyes, more natural-looking than hard-edged selections. It’s true that the rocks at the top of the scene are over-darkened by the graduated filter, but I think most people would accept that as a bit of ‘photographic licence’ and not worry about it too much. Fixing that with a precise mask would have taken a lot longer and might not look any more natural at the end of it. Besides, it’s very easy to overthink and overwork and image and lose your instinct for what looks ‘right’.
