The [ColorThe attribute of visual experience that can be described using the dimensions of Hue1. A tint or color specified by an angle on the HSV Color Wheel. Going counter-clockwise around the wheel, hues shift from red to yellow to green to cyan to blue to magenta and finally back to red. 2. The attribute of a color that permits it to be identified as a specific color. Hue combined with Saturation and Value fully defines a color., Saturation, and Brightness. Limits] tool automatically sets the White and Black limits from a selected color range. In the [Color Limits] option, click the [A] button. This automatically sets the Color Limits. You can also adjust the Color Limits using the up and down arrows or by typing a value in the appropriate field.

Clicking the [A] button takes the average of all RGB values in the image and moves the white and black points in 5% of the total pixels in the image. This means that the lightest 5% of pixels are all set to white, and the darkest 5% of all pixels are set to black, effectively reducing the gamma range by 10%.

The [White Limit] tool lets you manually set the white point of your image by selecting the pixels in your image that best represent white. Click the [Sample] button and select the point on your image that you want to set as white. All colors of equal or lighter values will be changed to white. You can also adjust the [White Limit] by modifying the [R], [G], and [B] boxes.

The [Black Limit] tool lets you manually set the black point of your image by selecting the pixels in your image that best represent black. Click the [Sample] button and select the point on your image that you want to set as black. All colors of equal or darker values will be changed to black. You can also adjust the [Black Limit] by modifying the [R], [G], and [B] boxes.

The [HistogramA type of graph that shows frequency data in two-dimensional rectangles. The width of each rectangle represents the class interval (in RIP-Queue, this is the section of the spectrum), while the height represents the number of occurrences (in RIP-Queue, this is the number of pixels with that color value).] tool (Figure 2) reflects the balance among Red, Blue, and Green colors in the image. The colors at the right of the scale are lighter, while the colors at the left of the scale are darker. The height of each vertical line for each color indicates the amount of that shade of that color in the image. The white pointer defines a curve; all points right of that curve (higher) are adjusted to be white. The black pointer defines another curve; all points left of that curve (lower) are adjusted to be black.

• Using the Histogram to set White and Black Limits - Each of the four histogram curves (Red, Blue, Green, and Average) acts independently from the others. For Red, Green, or Blue you can adjust the color balance and set the white and black points for each individual color. Select that color from the Channel drop-down list, and click and drag the white slider (for white) and the black slider (for black). You may also move the sliders or type values in the text boxes. If you select [RGB Average] the values set affect all colors.
• Using the Histogram - If you zoomed in on the image prior to using the histogram, the histogram shows the color balance of the enlarged area. This allows you to set the black and white points for the entire image based on that area.