Adobe Photoshop Tutorial. Copyright Michael B. Karbo.
20. Layer masks a la carte
Now comes 3 exercises where we use layer masks to work on color pictures. Along the way we look at the many possibilities to vary the brushes. Finally we talk about the Preset Manager dialog box, which is used to handle the various collections of brushes and color modes etc. But first a small exercise:
Photos from digital cameras often display great depth of field. If you want to highlight the motif, it can be smart to blur the background. That is easy to do in Photoshop, try this:
1. Open the picture fleur.jpg, which is on the home page for this booklet. There is a tall thin flower in the center of the picture. That has to stand out more clearly, therefore the background needs to be blurred.
2. You need to insert a copy of the picture on a new layer. That can be done quickly with the shortcut presses Control+a, Control+c, Control+v. Another smart method is to simply drag the layer’s beam down to the New Layer button and release it there; then a copy of the layer is inserted:
3. Then select the topmost layer (if it is not already selected). Choose menu items Filter --> Blur --> Gaussian Blur:
4. This excellent filter can blur the picture more or less depending on the Radius setting. Try to drag the slider towards the right to increase the value. The picture gets really burred:
5. Choose the value 3,5 pixels; that gives a suitable blur in the picture.
6. Now the top layer is blurred, but the picture exists in a sharp version on the layer below. Now you need to make a layer mask, which can blend the two pictures. The top layer still needs to be selected. Choose menu items Layer --> Add Layer mask --> Reveal All. That inserts a layer mask that shows all the picture content (the mask is white):
7. So the visible picture in the top layer is still blurred. Make a 200% enlargement, and select the brush tool (pres b).
8. Choose a soft brush in size 13 px.
9. Select the default colors by pressing d, and reverse them with x. Now paint with the brush across the flower, so picture data from the bottom layer ”peek through”. The idea is that the flower neeeds to be sharp (painted with black in the mask), while the whole background needs to be blurred:
10. Continue downward. Reverse the colors by pressing x, so you paint alternately with black and white in the mask. You might need a smaller brush if you want to make the really perfect mask.
11. Zoom out again and enjoy your picture!
12. Save the image file fleur.psd when you have achieved a good result.
Figure 45. The mask, which makes the flower stand out sharp on a blurred background.