The brightness and contrast, amount of true whites and blacks in an image, can be altered in several ways.
• The Adjustments > Brightness/Contrast panel from the Image menu. This gives blanket results across the entire image. For finer control, use one of the two methods below.
Choose Adjust ments > Levels from the Image menu.
The graph shows the range of tones, from darkest (left) to lightest (right). The left pointer indicates the point from which true black starts. All tones to the left of this point are black.The right pointer indicates the point from which pure white starts. All tones to the right of this point are white. The middle point indicates the mid-gray point.
So, move the left and right pointers to decrease or increase the purity of white and black, and contrast. Move the middle pointer to determine the overall brightness and darkness. The Channels option on the Levels window also allows you to change the tones within individual colours (eg for RGB you will also find Red, Green and Blue channels). This enables you to remove or create colour casts on your documents.
Dodging (to emphasize highlights, make lighter)
1. Zoom in to a 2:1 view;
2. Choose the Dodge tool from the Tools and select options from the palette;
3. Position the pointer on the area for dodging, drag to lighten.
NB If the tool is too thick or thin, select a different brush size from the Brushes palette.
To adjust the colours of parts of the document, rather than the whole document, use the tools below.
Burning (to subdue highlights, make darker)
1. Choose Burn from the Tools and select options from the palette;
2. Position the pointer on the area for burning, drag to darken.
Saturation (to purify/brighten the colour) and Desaturation (to dull the colour)
1. Choose Sponge from the Tools and select options from the palette;
2. Choose Saturate or DeSaturate from the palette;
3. Drag the pointer (now a sponge icon) over the area repeatedly. Each time this is done, the saturation increases;