Xerox 1235N Service Guide - Page 91

Adjusting color density and balance Over the life of the printer, colors may change. For example, reds may begin to take on a purple cast, or blues may take on a green cast. This happens during the normal use of a color printer and can be easily remedied by using the color adjustment procedure described in this section This front panel procedure involves printing a test page and adjusting the densities and colors based on the appearance of the test page. You may need to repeat this procedure and test your adjustments until you achieve the desired effect. Note At any time, you can reset the printer to the factory defaults by selecting Color Defaults from the Color Adjust Menu. Printing a Test Page 1. Press the Menu (1, 5) keys until you see Color Adjust. 2. Press Item (2, 6) keys and the printer prints the Color Balance test print. Interpreting the Color Balance test print The Color Balance test print contains numbered images that indicate possible adjustments that can be made. You can choose to make an adjustment to the Color Density, the Black Density, or the Color Balance. s The Black Density Images, numbered -3K...0,...+3K, show a lightness/darkness range of 30% halftones using black only. s The Color Density Images, numbered -3CMY...0,...+3CMY, show a lightness/darkness range of 30% gray halftones using three colors (cyan, magenta, yellow). s The Color Balance Images, numbered 0,10,11,...21, show variations of three-color gray. Each of these circles contains gray with tints of other colors. Color Balance and Density Adjustment Test Step 1. AdjustBlack Density until ìCurrentì = 30% Black Halftone. Repeat as needed. BLACK / GRAYSCALE -3K -2K Decrease -1K Current +1K 0 +2K +3K Increase Step 2. AdjustColor Density to match Black Density Squares from Step 1. Repeat as needed. CYAN + MAGENTA + YELLOW -3CMY -2CMY -1CMY Current 0 +1CMY +2CMY +3CM Decrease Increase Step 3. Step 4. AdjustColor Balance to match ìCurrent Circleì with Gray Reference. Repeat as needed. Iterate between Step 2 and Step 3 as needed. 16 21 10 15 Current 0 14 20 13 19 Xerox Corporation, 2000 ver 1.1 Gray Reference (30% Black Halfto abcdef abcdef abcdef abcdef 17 11 abcdef abcdef abcdef abcdef Density Rate Set Points Range: [80 - 100] Current Black Level: Current Cyan Level: 12 Current Magenta Level: Current Yellow Level: 18 Developer Bias Range: [251 - 550] Current Black Level: Current Cyan Level: Current Magenta Level: Current Yellow Level: Service Guide 77