Adobe photoshop cs2 Manuale Utente

ADOBE PHOTOSHOP CS2 

The image changes to Threshold mode, and a high-contrast preview image appears. The visible areas of the image 
indicate the lightest parts of the image if you are dragging the white slider, and the darkest parts if you are dragging 
the black  slider. If a color channel  is  selected  in  the Levels dialog box, the  black area indicates  where none of the  given  
color component exists. 

Slowly drag the slider to the center of the histogram to identify areas in the image that are being clipped

(completely black or completely white). Use the pixels in these areas for targeting the black point and white point in
your image.

Choose Image > Adjustments > Threshold.

Select Preview.

To identify a representative highlight, drag the slider to the far right until the image becomes pure black. Drag the

slider slowly toward the center until some solid white areas appear in the image, and place a color sampler on one of
the areas. Press Shift to temporarily access the Color Sampler tool.

To identify a representative shadow, drag the slider to the far left until the image becomes pure white. Drag the

slider slowly toward the center until some solid black areas appear in the image, and place a color sampler on one of
the areas.

Click Cancel to close the Threshold dialog box without applying changes to the image.

You can use the Info palette readouts of the two color samplers to determine your highlight and shadow values.

The Exposure dialog box is designed for making tonal adjustments to HDR images, but it works with 8-bit and 16­
bit images. Exposure works by performing calculations in a linear color space (gamma 1.0) rather than the image’s
current color space.

Choose Image > Adjustments > Exposure.

Set any of the following options:

Adjusts the highlight end of the tonal scale with minimal effect in the extreme shadows.

Darkens the shadows and midtones with minimal affect on the highlights.

Adjusts the image gamma, using a simple power function. Negative values are mirrored around zero (that

is, they remain negative but still get adjusted as if they were positive).