CHAPTER 15 THE IMPORTANCE OF LEVELS AND CURVES 233The Absolute Minimum
Even the most washed-out images contain valuable information. Photoshop and
Elements are capable of pulling this information out of an image using Levels and
Curves. By using Threshold and histograms, you can see where information lies and
adjust brightness values appropriately. Keep these tips in mind when experimenting:
■ Histograms of an image are available in three places: Image, Histogram,
Image, Adjustments, Threshold, and Image, Adjustments, Levels.
■ Choose Image, Histogram and then move your mouse over the histogram to
see the number of pixels that use a specific brightness value.
■ Choose Image, Adjustments, Threshold in Photoshop or Photoshop Elements
to view a histogram of an image. Move the slider to the left to see the darkest
parts of the image; move to the right to see the lightest parts of the image.
■ The x-axis of the histogram maps the 256 brightness values available for
each pixel; the y-axis maps the total number of pixels in the image at a spe-
cific brightness value.
■ A common repair technique using Curves is to use the “S” shape. Choose
Image, Adjustments, Curves and create an S shape to increase brightness and
contrast in the image.