Fixing Exposure with Shadow/Highlight in Photoshop cs - dummies

Fixing Exposure with Shadow/Highlight in Photoshop cs

The new Shadow/Highlight adjustment in Photoshop cs is a great new feature that offers a quick and easy method of correcting the lighting in your photos. It allows you to correct over- and underexposed areas in your image. This command works well with subjects photographed with the light source coming from behind (backlit) and consequently have a dark foreground. The new adjustment is also helpful for bringing out the detail in harsh shadow areas in subjects shot in bright, overhead light. This command doesn’t really correct overall exposure. Instead, it lightens or darkens pixels according to the luminance (brightness) of the surrounding pixels, technically called a local neighborhood.

The Shadow/Highlight command also has a Midtone Contrast slider, Black Clip, and White Clip options for adjusting the overall contrast of the image.

Follow these steps to get familiar with this new addition to the adjustment arsenal:

1. Open an image in dire need of repair and choose Image –> Adjustments –> Shadow/Highlight.

Unlike many other image adjustments, when the dialog box appears, it automatically applies the correction to your preview. If you don’t see any change, make sure you have selected the Preview check box. The default settings found in the dialog box are meant to correct backlit images, so they may or may not do the right correction job for you as they are set.

2. Move the Amount slider to adjust the amount of correction for your Shadows and/or your Highlights.

The higher the percentage, the lighter the shadows and the darker the highlights. You can also enter a value in the percentage text box.

3. If you’re happy with the results, click OK and be done with the adjustment. However, if you crave more control, click the Show More Options check box at the bottom of the dialog box.

A whole array of sliders magically appears.

4. Drag the Tonal Width slider to increase or decrease the range of tones adjusted in the shadows or highlights.

The lower the percentage, the narrower the range of tones that will be affected. For example, by using a very low percentage, only the darkest parts of the shadow or the lightest parts of the highlight are corrected. Similarly, by using a high percentage, you include a wide range of tones, including midtone areas. The appropriate percentage to use varies among images, so start with the default setting of 50% and work in small increments from there.

If, when lightening the shadow areas, you find the midtones and highlights getting too light as well, reduce the Tonal Width percentage of the Shadows. But if you start seeing artifacts, you have set the percentage too high.

5. Drag the Radius slider to increase or decrease the number of pixels used in the local neighborhood.

Remember that this command uses the luminance of surrounding pixels, called local neighborhood, for adjusting the shadows and highlights. The best local neighborhood size depends on the particular image, so play with this slider and view the results. If the Radius is too small, your main subject may lack contrast. Conversely, if it’s too large, your background may be overly bright or dark. Adobe recommends setting the radius to approximately half the size of the main subject in your image. So if your subject takes up roughly 600 pixels, then set your radius to 300 pixels. Choose Show Rulers on the View menu and set your Units to pixels in your Preferences.

6. Make additional changes in the Adjustments area as needed:

Color Correction: Available for color images only, this control enables you to correct the colors in only the adjusted portions of your image. Often when you increase or decrease the Amount of Shadows or Highlights, you bring out the “hidden” colors. Generally, higher Color Correction values make colors more saturated, whereas lower values make colors more desaturated.

Brightness: Available for grayscale images only, this command adjusts the brightness. Move the slider left to darken and right to lighten.

Midtone Contrast: This control adjusts the contrast in the midtone areas. Move the slider left to reduce contrast and right to increase contrast. Just be aware that when you increase the Midtone Contrast, you may also undesirably darken shadow areas and lighten highlight areas.

Black Clip/White Clip: These values specify how much of the shadows (black) and highlights (white) are clipped to the new shadow (level 0) and highlight (level 255) colors in the image. Clipping causes the remaining levels to be redistributed between the brightness levels of 0 and 255. Higher percentages increase the tonal range and therefore create greater contrast, but when the value is too high it causes lack of detail in the shadows and highlights.

These values specify how much of the shadows (black) and highlights (white) Photoshop clips, making the new shadow (now level 0) and highlights (now level 255) colors in the image.

7. Click the Save As Defaults button to save and make your settings the defaults.

If you want to reset the setting back to the original defaults, press Shift and click the Save As Defaults button. You can save as many settings as you want. Click the Load button to reload a particular setting.

8. Click OK to apply the adjustment and exit the dialog box.