This tutorial is among the simplest Photoshop tricks there is [yet you need some basic knowledge to understand it]. Although for some it may seem hard, if you look over this tutorial a couple of times, you will understand it.

To mask or not to mask?

I bet that most of you have heard of layer masks but don't quite know what they are. This tutorial explains how to work with layer masks on one image [the two image work-about will be explained in another tutorial]. Now, layer masks are masks which cover up some elements of the picture whilst revealing others, just like a normal mask does: it covers the face but at the same time allows the eyes to be seen.

What are we going to do today?
We are going to apply some effects on an image and conceal them using a layer mask.

Step I - The base image

The base image is that of a flower poking through a fence. In order to have a succesful composition using layer masks you should use two images which are appropriate in dimension and have clear, visible objects. However, this is not the case as we will be working on one image.

Step II - Turning the background into a layer

Locked layers, such as backgrounds do not support layer masks. Therefore, we need to change the background layer into an editable layer. The simplest way to do this is to duplicate the background and then delete it [you can easily spot the background as it is the only layer with a lock near it].

Step III - Applying the layer mask

Now that we have a layer, we can apply the mask. On the bottom of the layers box you will see a small button that depicts a square with a circle in it. By clicking on it, a new blank layer will appear that will be linked to the selected one. That will be our layer mask. Note that by selecting the layer mask, the brushes will turn from colour to black and white.

Step IV - Where do we go from here?

Well, now we need to work with the background layer. If you have deleted it by mistake, just duplicate the existing one. If not, select the background layer. Next, we have to apply some Hue changes in order to make the masking effect visible. For more info on how to do this, please consult our Hue Tutorial. Once in the Hue/Saturation menu, move the Hue slider to the right or set the value to ~ -50. As you can see in the picture below, both the flower and the fence have changed colours.

Step V - The fun part

It's time to work with the layer mask! Select it and notice that the brushes turn to black and white. Black ERASES while white RESTORES. So if you made a mistake and want to fix it, use the white brush in order to reveal the deleted fragments of the masked image. Gray and variations of gray can also be used. They offer a smooth transitional effect between the layer mask and the base image. The same effect can be achieved by using gradients.

Ok, enough talk. Let's get down to business. With the brush tool selected start working on the layer mask. You will see that the deleted sections are no longer greenish, but blueish like the original photo. One thing is very important: always work INSIDE the layer mask [Photoshop has the tendency to deselect what you are working on so I've brushed over a base image many times :) ].