Let's use this photo (left) of a beautiful hula dancer in Hawaii to practice with the selection tool . We'll put a soft-edged oval-shaped selection ellipse around her, then invert the selection so that everything outside the oval is selected, then we will delete the selection which will cause the deleted area to be replaced with the background colour (yellow). As a final step we will crop the image, giving something like the image at right (without the word 'sample' of course).

Actually you may not find the selection tool to be very useful for working with photographs, because not many photographs are made up of simple shapes like rectangles or ovals. Even if you take a photograph of a rectangular wall, it will only appear as a rectangle in the photo if the axis of the lens is perpendicular to the wall.

Choose the the selection tool then set the selection type to 'ellipse' (oval), the mode to 'replace' and the feathering radius to 40 pixels to give a very blurred edge the selection. Now select the dancer. If your selection is not good then deselect with Ctrl-D and try again. Once the selection is satisfactory, try dragging any point inside the selection - notice that the selection ellipse moves and so do its contents, leaving behind the background colour. Undo the move (Ctrl-Z). Now try Alt-dragging i.e. hold down the Alt key and drag the selection - notice that selection ellipse moves along with a copy of its contents while the original image is not changed. Undo the move (Ctrl-Z). If you want to move the selection outline (the 'marquee') then choose the Move tool   then place the cursor inside or on the marquee, hold down the right mouse button, and then drag the marquee to a new position.

Now invert the selection with Select > Invert so that the edges of the picture are selected. We are about to delete the selected area and replace it with the background colour but before we do so you should go to the materials palette (display it by pressing F6 if necessary) and set the background colour to light yellow. Now delete the selected area by pressing the delete key on the keyboard. Finally, use the cropping tool to crop the picture.

Don't you agree that the 'vignette' effect concentrates attention on that pretty smile? (It's the kind of smile she would only give to someone she really liked the look of, don't you agree?)

Here's another exercise to give you more practice with feathering and with the selection tool.

Here's the procedure:

1. Choose the selection tool (or just press 'S') and make sure that the selection type is 'circle' and the feathering is zero (we want feathering but we will add it AFTER making our selection so that we can control it more accurately).
    
2. Make a circular selection by dragging from the man's nose in any direction until you have a circle that encloses his hat and necklace.
    
3. Now choose Selections > Modify > Feather... and double-click the blue title bar of the dialog so that you can see the whole picture (the checkerboard pattern of squares is the symbol for transparent or unselected areas). Adjust the feathering until you have desired blurring of the edges of the selection (a feathering of about 60 would be good) then close the dialog. The selection circle looks bigger now because it shows you all the area that is selected, including the pixels in the feathered area that are 'partially selected'.
    
4. We have selected the man's face but we know that we actually want to modify everything BUT the man's face (by taking the colour away) so choose Selections > Invert to select the desired area.
    
5. The final step is to take the colour away from the selected area with Adjust > Hue and Saturation > Hue/Saturation/Lightness. The 'saturation' is the intensity of the colours so take this slider down to its minimum position of -100.
    
6. To see the finished picture without the distracting marching ants, press Ctrl-D to deselect the selection.
    
7. As usual, save your finished picture in the JPEG (compressed) format. Recall that the pspimage format is good for pictures that are not yet finished since this format retains all the information about layers and so on.