[TUTORIAL] Masking: How to take a background out of a picture.
1. Open your file you want to edit. Immediately go to File>Save As so you don’t save over your original file. Save as either a layered PSD or layered TIFF file. Next, create a duplicate of your layer to work on. This is a good habit to get into since it’s never a good idea to work on the main layer.
To duplicate the layer, you can either click and drag the layer to the ‘Create A New Layer’ icon next to the ‘Delete Layer’ Trash icon or right-click on the layer title and select ‘Duplicate Layer’. Then you should hide the original layer by clicking the eye next to the layer and name your new layer by double clicking on the title of the layer.
2. Then click on the Edit in ‘Quick Mask Mode’ or you can use the quick key ‘Q’.
3. Select the ‘Brush Tool’ or you can use the quick key ‘B’.
4. Make sure that your brush color is set to black so that you are creating the mask over the areas you want to mask out. For large areas around the main subject in your image, increase your brush size by hitting the ‘]’ key or decrease the brush size by hitting the ‘[‘ key. Make sure that the brush is set to any size ‘Hard Round’ brush with the ‘Opacity’ set to 100% and ‘Flow’ set to 100%. This will make certain that you get every area covered.
If you make a mistake, don’t worry. You can change the brush color to white and color over your mistakes. For areas where there is a lot of detail you can carefully mask around those edges by using a ‘Soft Round’ brush. To really see the details, ‘ZOOM-IN’ to the picture by pressing ‘CTRL+’ and to ‘ZOOM-OUT’ just press ‘CTRL-‘. These will be the basic things you will always do when you need to mask out an image. With practice, you will become faster and eventually better with each image over time.
Once you’ve finished masking, you should have something that looks like the image below.
5. Now click on Edit in ‘Standard Mode’ or you can use the quick key ‘Q’. Now you will see that the area you’ve masked over has changed into a selection (the dancing ants!).
6. Next you will go to Select>Save Selection.
7. The ‘Channel’ should say “New” and then name your selection whatever you want. For this tutorial I chose girl-selection. Then press ok. Congratulations, now you have saved your first selection!
8 Since we’ve saved the selection, now we must drop a layer mask onto the picture layer. Go to Layer>Add Layer Mask>Reveal All. This will create a layer mask that doesn’t ruin your original image.
9. Now you will go to Select>Load Selection. Choose the selection that you saved. The dancing ants have now appeared! The only problem is that it has the girl selected and not the background, so we must invert the selection. Go to Select>Inverse and the selection should change. Next, we would like to get rid of the background, so you will need to fill it with White to delete the selected area. Hit ‘X’ to switch the foreground and background colors from Black/White to White/Black. If you don’t have Black or White as the main colors for some reason, you can hit Shift+D to return the colors back to default Black and White. Then hit delete. You should then have the background ‘deleted’. However, this is reversible and doesn’t actually alter your original image until you choose the ‘apply layer mask’ option by right-clicking over the layers’ mask next to the layer title, go to Layer>Layer Mask>Apply or flatten the image by going to Layer>Flatten Image.
10. Essentially you’re finished! Now you can place any type of background behind your edited picture.