overscan. An “X” marks the electrical center of the pattern.
Pattern Usage: Used to check and adjust for the proper geometry of a display, including picture centering, size, trapezoid (keystone) correction, pincushion (bow) correction, and linearity. Horizontal and vertical centering controls should be adjusted to center the pattern on the display screen. The chevrons at each of the four edges make it particularly easy to see whether there is equal amount of overscan at the sides or at the top and bottom of the pattern.
The horizontal and vertical size controls should then be adjusted for the desired amount of either overscan or underscan. If overscan is desired, a display should usually be adjusted for slightly less than 5% overscan. The horizontal and vertical overscan should be adjusted to be an equal percentage, as judged by the overscan tic marks.
Trapezoid correction control(s) should be adjusted to make the pattern’s edges parallel to the edges of the display screen. The brighter crosses in the corners of the pattern should be adjusted to be equal distances from the edges of the screen (don’t worry yet about the shape of the lines between the crosses).
Pincushion correction controls should be adjusted to straighten the lines between the brighter corner crosses. Use the edge of the display screen or a flexible straightedge, such as a yardstick, to judge the straightness of the lines.
The horizontal linearity control should be adjusted to make the pattern boxes all the same width. The vertical linearity control should be adjusted to make the pattern boxes all the same height.
Anamorphic
Pattern Description: 32 horizontal by 18 vertical lines crosshatch forming 16:9 aspect ratio pattern. When viewed on display device with standard 4:3 aspect ratio, pattern will appear stretched vertically, with crosshatch boxes forming tall rectangles. When pattern is displayed in
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