Image Processing Reference
The Exposure slider determines the brightness of the entire image, setting the
brightest value the image will contain. If you are familiar with the Levels control,
Exposure works the way the right slider in the Levels dialog does (Figure 2.23).
The far left slider adjusts the black, or shadow point, the center slider adjusts the
overall brightness of the image, and the right hand slider adjusts the highlight, or
white point, of the image.
The Exposure, Shadows, and
Brightness sliders work the same
way the Input Level controls in
Photoshop and Photoshop Ele-
ments work. The Exposure control
is the same as the right slider,
Shadows the left slider, and
Brightness the center slider.
The best way to monitor your adjustments with the Exposure slider is to use the
Alt/Option key while making adjustments Figure 2.24 shows what the preview display
looks like when using this method. The colored pixels show which color channel is
clipping. White pixels indicate all color channels are being clipped and will result in
pure white. The Alt/Opt key method is much more detailed than the simple shadow
and highlight clipping checkboxes, especially for exposure and shadow adjustments,
because it shows each color channel as the image is adjusted.
Figure 2.24 Pressing the Alt/Opt key while adjusting the Exposure slider shows each color channel as it
becomes clipped. White indicates all three colors are clipped and will be displayed as pure white in the