The Equalize filter redistributes the brightness values of the pixels in an image so that they more evenly represent the entire range of brightness levels. When you apply this command, Photoshop Elements finds the brightest and darkest values in the composite image. It then remaps them so that the brightest value represents white and the darkest value represents black. Photoshop Elements then equalizes the brightness—that is, distributes the intermediate pixel values—evenly throughout the grayscale.
The Gradient Map filter maps the grayscale range of an image to the colors of a specified gradient fill.
- To choose from a list of gradient fills, click the triangle to the right of the gradient fill displayed in the Gradient Map dialog box. Click to select the desired gradient fill, and then click in a blank area of the dialog box to dismiss the list.
- To edit the gradient fill currently displayed in the Gradient Map dialog box, click the gradient fill. Then modify the existing gradient fill or create a new gradient fill.
The Invert filter inverts the colors in an image. Use this command, for example, to make a positive black-and-white image negative or to make a positive from a scanned black-and-white negative.
Note: Because color print film contains an orange mask in its base, the Invert command cannot make accurate positive images from scanned color negatives. Be sure to use the proper settings for color negatives when scanning film on slide scanners.
When you invert an image, the brightness value of each pixel is converted into the inverse value on the 256‑step color-values scale. For example, a pixel in a positive image with a value of 255 is changed to 0.
The Posterize filter lets you specify the number of tonal levels (or brightness values) for each channel in an image. It then maps pixels to the closest matching level. For example, choosing two tonal levels in an RGB image gives six colors, two for red, two for green, and two for blue.
This command is useful for creating special effects, such as large, flat areas in a photograph. Its effects are most evident when you reduce the number of gray levels in a grayscale image. But it also produces interesting effects in color images.
If you want a specific number of colors in your image, convert the image to grayscale and specify the number of levels you want. Then convert the image back to the previous color mode, and replace the various gray tones with the colors you want.
The Threshold filter converts grayscale or color images into high-contrast, black-and-white images. You can specify a certain level as a threshold. All pixels lighter than the threshold are converted to white; and all pixels darker are converted to black. The Threshold command is useful for determining the lightest and darkest areas of an image.
- From the Layers panel or Layer menu, create a new Threshold adjustment layer, or open an existing Threshold adjustment layer.
- To change the image to black and white, drag the slider below the histogram until the threshold level you want appears at the top of the dialog box, and click OK. As you drag, the image changes to reflect the new threshold setting.
- To identify a representative highlight, drag the slider to the right until the image is pure black. Then drag the slider back until some solid white areas appear in the image.
The Photo Filter command mimics the technique of putting a colored filter in front of the camera lens. A colored filter adjusts the color balance and color temperature of the light transmitted through the lens and exposing the film. The Photo Filter command also lets you choose a color preset to apply a hue adjustment to an image. If you want to apply a custom color adjustment, the Photo Filter command lets you specify a color using the Adobe Color Picker.
Warming Filter (85) and Cooling Filter (80)
Color conversion filters that tune the white balance in an image. If an image was photographed at a lower color temperature of light (yellowish), the Cooling Filter (80) makes the image colors bluer to compensate for the lower color temperature of the ambient light. Conversely, if the photo was taken at a higher color temperature of light (bluish), the Warming Filter (85) makes the image colors warmer to compensate for the higher color temperature of the ambient light.
Warming Filter (81) and Cooling Filter (82)
Light balancing filters for minor adjustments in the color quality of an image. The Warming Filter (81) makes the image warmer (yellower) and the Cooling Filter (82) makes the image cooler (bluer).
Apply a hue adjustment to the image depending on the color preset you choose. Your choice of color depends on how you're using the Photo Filter command. If your photo has a color cast, you can choose a complement color to neutralize the color cast. You can also apply colors for special color effects or enhancements. For example, the Underwater color simulates the greenish-blue color cast caused when photographing underwater.
- Select the Color option, click the color square, and use the Adobe Color Picker to specify the color of a custom color filter.