• Create BookmarkCreate Bookmark
  • Create Note or TagCreate Note or Tag
  • PrintPrint
Share this Page URL
Help

Chapter 8. Understanding Colors and Chan... > Using the Threshold and Posterize Ad...

Using the Threshold and Posterize Adjustments

The Threshold adjustment splits an image into black and white, based on the original brightness levels of the pixels. It's useful for locating the darkest and lightest pixels in an image, or for creating some great looking black and white special effects. The Posterize adjustment creates a simpler image by reducing the number of colors. It's useful for creating an image with a clipart look, or for reducing the number of colors in preparation for the Web.

Use the Threshold Adjustment

Open an image.

Click the Image menu, point to Adjustments, and then click Threshold.

Drag the Threshold slider to the right or left to change the point in which black and white are defined.

For example, setting the threshold slider to a value of 75 creates an image where all pixels with a brightness value of 75 or less are black, and all pixels with a value of 76 or higher are white.

Click OK.


PREVIEW

                                                                          

Not a subscriber?

Start A Free Trial


  
  • Creative Edge
  • Create BookmarkCreate Bookmark
  • Create Note or TagCreate Note or Tag
  • PrintPrint