Using layer masks in Photoshop: a basic guide
Program(s)+version: Photoshop CS5
Involves: Layer masks, lasso tool
Translatable: should work in all programs/versions that have layers and allow to create layer masks
Steps: about 6 for the example, the rest is a guide more than a step-by-step tutorial
Difficulty: Beginner
A little guide on how to do layer masks and an example on how to change the background of an image using them.
Using Layer Masks in Photoshop
- A Basic Guide -
Since layer masks are a very essential part of my icon and/or graphic making process, here's a small roundabout on what they do and how you can use them e.g. for getting rid of the background in an image.
What layer masks do
Using layer masks is the undestructive way of "erasing" pixels from your image.
With the eraser in Photoshop, you literally delete parts of your image, meaning you lose them for good. With a layer mask, you just "hide" the unwanted parts of your image; you make them invisible. The advantage of this is that you can always go back and make corrections to your mask if you accidentally made a mistake but didn't notice until the very end. For example, you cut a person out from it's background and after you're almost done, you notice that the person somehow lost it's nose in the process and you want to get it back. If you used the eraser, you'll have a big problem now, you either have to live with your poor noseless soul (sorry, it's a really crappy example, I know) or do all the hard work again. With a layer mask on the other hand, you can just go back and make those parts of the image magically reappear again.
Basicly, this is just the long-winded way of me saying that the eraser is evil.
Layer masks are the good guys, and they can be used for a lot of things once you've understood the basic principle of them.
How to create a layer mask and how it all works
To create a layer mask, you just have to select the layer containing your image and then go to this little button here, right underneath the layer palette:
This will create a layer mask for this layer, you can see this by having a look at the layer palette, there should have appeared a white filled rectangle right next to the thumbnail of your image:
If you click the white rectangle, the "mask", you can simply paint on it using a brush. When you paint on it with black, these areas of the image will become invisible. Painting with white on it reveals the image again. Painting with grey will make the image gradually more transparent, depending on the shade of grey you use.
It's not that difficult after all, is it?
Instead of using a brush to paint in the mask, you can also make a selection on it and fill this selection with black or white or grey. I will use this method in the following example.
An example:
How to use a layer mask to change the background behind a person
Note: You can use this technique on larger images as well as on icons. I am using a mid-sized graphic here for better visuality.
I have an image with a person and I want to put that person onto a different background, a texture for example. To do this, I create a layer mask as described above, then I use the lasso tool
to make a selection around the person:
It will be easier if you zoom in a bit to do this, although it doesn't have to be perfect at this point.
When I'm done with the selection, I invert it by pressing Ctrl + Shift + i on the keyboard, so the marching ants will now cover the background instead of the person.
You could have made the selection around the background from the start, of course, but I find it a lot easier to do it this way around.
Now, making sure that I have selected the layer mask-thumbnail in the layer palette (and not the image thumbnail), I fill my selection with black and the background will vanish.
This is how the image and the layer mask are supposed to look like:
Now I can drag the texture that I want to use as a background underneath my image to see it how they blend together - for demonstration purposes I will just use an ugly dark purple color fill layer instead of a texture here; you should obviously aim for something prettier than that:
You can see that my selection was not very good to begin with, you can still see some light blue lines where the sky from the original background shines through. So that means that there's still some work to do.
To finetune the mask, I zoom in a lot (to about 200-400% or more) and use a very small brush (1-3 pixel, sometimes more; it depends on the image size that you are working on) to paint in black over these light blue lines to make them disappear. Again, you have to paint in the mask here, not onto the image.
When I think I'm done, I zoom out to 100% to see how it looks:
It's a lot better than before, but I still don't like the hard edges on the right side of the armour, especially on the right shoulder, it still looks like an obvious cut-out to me. So, I go and zoom in again and do the same as before, but this time I will use a larger and less hard brush to carefully paint over these parts with black to - hopefully - blend them in a little better:
And finally, it looks good enough to me:
Adding a quick coloring and a more beautiful background (texture here by spooky-window) might give us this, for example:
Of course, there's a lot more that you can do with layer masks, these are just the very basics and a rather simple practical example. You might want to experiment a little for yourself, painting on the mask with different kinds of brushes, changing the opacity of it, using harder or softer brushes, using a gradient... well, and whatever else you can think of.
Additional info:
If you're photographically interested and want to dig really deep into the realms of masking and see what great things can be achieved with them, I recommend a read of this very amazing tutorial by Tony Kuyper. You most definitely won't want or need this for creating something as small as icons or simple fanart, but if you work with larger graphics and especially with photographs, this can actually be a lot of fun to play around with.
Well, and that's it. I hope I didn't forget anything important and as usual, if something I said doesn't make sense or you have further questions, just ask. :)
Involves: Layer masks, lasso tool
Translatable: should work in all programs/versions that have layers and allow to create layer masks
Steps: about 6 for the example, the rest is a guide more than a step-by-step tutorial
Difficulty: Beginner
A little guide on how to do layer masks and an example on how to change the background of an image using them.
Using Layer Masks in Photoshop
- A Basic Guide -
Since layer masks are a very essential part of my icon and/or graphic making process, here's a small roundabout on what they do and how you can use them e.g. for getting rid of the background in an image.
What layer masks do
Using layer masks is the undestructive way of "erasing" pixels from your image.
With the eraser in Photoshop, you literally delete parts of your image, meaning you lose them for good. With a layer mask, you just "hide" the unwanted parts of your image; you make them invisible. The advantage of this is that you can always go back and make corrections to your mask if you accidentally made a mistake but didn't notice until the very end. For example, you cut a person out from it's background and after you're almost done, you notice that the person somehow lost it's nose in the process and you want to get it back. If you used the eraser, you'll have a big problem now, you either have to live with your poor noseless soul (sorry, it's a really crappy example, I know) or do all the hard work again. With a layer mask on the other hand, you can just go back and make those parts of the image magically reappear again.
Basicly, this is just the long-winded way of me saying that the eraser is evil.
Layer masks are the good guys, and they can be used for a lot of things once you've understood the basic principle of them.
How to create a layer mask and how it all works
To create a layer mask, you just have to select the layer containing your image and then go to this little button here, right underneath the layer palette:
This will create a layer mask for this layer, you can see this by having a look at the layer palette, there should have appeared a white filled rectangle right next to the thumbnail of your image:
If you click the white rectangle, the "mask", you can simply paint on it using a brush. When you paint on it with black, these areas of the image will become invisible. Painting with white on it reveals the image again. Painting with grey will make the image gradually more transparent, depending on the shade of grey you use.
It's not that difficult after all, is it?
Instead of using a brush to paint in the mask, you can also make a selection on it and fill this selection with black or white or grey. I will use this method in the following example.
An example:
How to use a layer mask to change the background behind a person
Note: You can use this technique on larger images as well as on icons. I am using a mid-sized graphic here for better visuality.
I have an image with a person and I want to put that person onto a different background, a texture for example. To do this, I create a layer mask as described above, then I use the lasso tool
to make a selection around the person:
It will be easier if you zoom in a bit to do this, although it doesn't have to be perfect at this point.
When I'm done with the selection, I invert it by pressing Ctrl + Shift + i on the keyboard, so the marching ants will now cover the background instead of the person.
You could have made the selection around the background from the start, of course, but I find it a lot easier to do it this way around.
Now, making sure that I have selected the layer mask-thumbnail in the layer palette (and not the image thumbnail), I fill my selection with black and the background will vanish.
This is how the image and the layer mask are supposed to look like:
Now I can drag the texture that I want to use as a background underneath my image to see it how they blend together - for demonstration purposes I will just use an ugly dark purple color fill layer instead of a texture here; you should obviously aim for something prettier than that:
You can see that my selection was not very good to begin with, you can still see some light blue lines where the sky from the original background shines through. So that means that there's still some work to do.
To finetune the mask, I zoom in a lot (to about 200-400% or more) and use a very small brush (1-3 pixel, sometimes more; it depends on the image size that you are working on) to paint in black over these light blue lines to make them disappear. Again, you have to paint in the mask here, not onto the image.
When I think I'm done, I zoom out to 100% to see how it looks:
It's a lot better than before, but I still don't like the hard edges on the right side of the armour, especially on the right shoulder, it still looks like an obvious cut-out to me. So, I go and zoom in again and do the same as before, but this time I will use a larger and less hard brush to carefully paint over these parts with black to - hopefully - blend them in a little better:
And finally, it looks good enough to me:
Adding a quick coloring and a more beautiful background (texture here by spooky-window) might give us this, for example:
Of course, there's a lot more that you can do with layer masks, these are just the very basics and a rather simple practical example. You might want to experiment a little for yourself, painting on the mask with different kinds of brushes, changing the opacity of it, using harder or softer brushes, using a gradient... well, and whatever else you can think of.
Additional info:
If you're photographically interested and want to dig really deep into the realms of masking and see what great things can be achieved with them, I recommend a read of this very amazing tutorial by Tony Kuyper. You most definitely won't want or need this for creating something as small as icons or simple fanart, but if you work with larger graphics and especially with photographs, this can actually be a lot of fun to play around with.
Well, and that's it. I hope I didn't forget anything important and as usual, if something I said doesn't make sense or you have further questions, just ask. :)