Layers Part 4
Adjustment layers can be very, very important! As
you probably know Photoshop has advanced filters that can artificially
change the brightness, contrast, sharpness and levels of a picture.
Although these options are of the highest quality when they are
applied to a picture they permanently change that picture. For example,
changing the contrast of a picture tends to wash out some of the
finer tones. This is no problem provided that you do not want to
change the contrast back down again. What happens if you've spent
hours on a picture only to realise that the contrast was too high
after all! If you now wanted to turn the contrast back down a bit
you will loose the fine tones that used to exist. As a result and
the quality of the picture will be much less than it could have
The solution to this problem is to add an Adjustment
Layer. An Adjustment Layer will apply a correction (such as a contrast
change or levels etc.,) to all layers below it. Because it does
not permanently change those layers below it you can alter
the picture correction at any time you like. Make no mistake using
Adjustment Layers can save you hours of work if something goes wrong!
So how do we use the Adjustment Layers? They are added
pretty much the same way as any layer. To add an Adjustment Layer
just click on the add Adjustment Layer Icon (encircled in red below).
Up will pop all the adjustment options you can alter
as can be seen below:
I've chosen the Brightness/Contrast
Layer... option which on a very high setting changed
Below is what the final layers palette looks like
with the adjustment layer added.
The background layer has the original picture and
the top layer is a rather weird looking adjustment layer. Notice
that the Adjustment Layer is split into two parts with a link icon
in-between them. The left section is the actual adjustment icon.
If you double-click on this icon it will allow you to change the
adjustment settings (i.e. turning the contrast up and down etc).
On the right is a masking effect. Every Adjustment Layer comes with
a mask effect as default. Masking effects are used in a similar
way to layers but will be dealt with in another article since it
will complicate the situation. For now just accept that a mask effect
is added with and adjustment layer and having it will allow you
to rub out parts of the Adjustment layer so that the picture underneath
Okay this is not really a vital thing to learn but
I'm adding it to make this article more complete. A normal layer
can be converted into a clipping layer. What this means is it will
act as a stencil so that the layer above it will only appear in
the shape of the stencil below. Basically this is used to create
those effects were you want one picture below to show through the
one above it. I know that's about as clear as mud to you, so let
me show you what I mean.
Start a new picture with a white background. Then
open up the zebra picture found in your Photoshop samples folder,
or any picture you like, and paste that picture over the top of
the white background.
Then add a new blank layer to use as a clipping layer.
The final layer setup should look like this:
The zebra is at the top, the background is at the
bottom and the layer we are going to use as a clipping layer is
in the middle. Now, go in-between the zebra
layer and layer 1 and hold down the
Alt key on your keyboard. The
mouse pointer should turn into a pair of overlapping circles as
can be seen in the above picture. Once the mouse pointer changes
left-click with the mouse and you will get the following setup:
Notice that the zebra layer has been moved to the
right and has a downward arrow on it. This means that the zebra
picture will only appear over what is painted in the clipping layer.
Try painting on the clipping layer (layer 1) and you will see what
I mean. You should get an effect something like this:
That's it for the layers guide. You should now understand
almost everything about using layers. As time goes on you will just
learn how best to use them by instinct. The next step after layers
is to understand masking because they are similar subjects. Masking
is almost the same as layers but allows you to create special kinds
of masking effects that can have gradients. Understanding Selections,
Layers and Paths is half the fight with Photoshop, once that is
mastered the rest should follow quite quickly.