Christie Digital Systems CSP70 user manual Gamma, Filter

Section 3: Operation

will not be as bright as they could be and the overall image will be dim. For best results, start with a low value and increase so that whites remain bright but are not distorted or tinted, and that light areas do not become white (i.e., are “crushed”).

NOTE: If the environment lighting changes, an adjustment of Gamma is recommended (see below).

Brightness

(SHORT CUT: Press Bright and adjust the slidebar.)

“Brightness” increases or decreases the amount of black in the image (0-100). For best results, keep close to 50. Start with a high value and decrease so that dark areas do not become black (i.e., are “crushed”). Conversely, high brightness changes black to dark gray, causing washed-out images.

NOTE: Adjust brightness before adjusting contrast, since the brightness setting will have an affect on contrast.

Gamma

(SHORT CUT: Press Gamma and adjust the slidebar.)

“Gamma” is a global setting that determines what gray shades are displayed between minimum input (black) and maximum input (white) for all signals. A good gamma setting helps to optimize blacks and whites while ensuring smooth transitions for the “in-between” values utilized in other colors. Thus, unlike “Brightness” and “Contrast” controls, the overall tone of your images can be lightened or darkened without changing the extremes, and all images will be more vibrant while still showing good detail in dark areas.

Gamma is used to fine tune the gamma table currently in use, ranging from 1 – 3 (2.5

=default). If excess ambient light washes out the image and it becomes difficult or impossible to see details in dark areas, lower the gamma setting to compensate. This will improve contrast while maintaining good details for blacks. Conversely, if the image is washed out and unnatural, with excessive detail in black areas, increase the setting. In high ambient light conditions, lower gamma may produce better results than higher gamma. Gamma of 2.5 (default) indicates the gamma table has not been adjusted. For more information, refer to Advanced Image Settings, Gamma Table submenu. Again, good gamma improves contrast while maintaining good details for blacks.

Filter

The proper filter setting is automatically set for virtually all signals, and rarely needs to be changed. It applies a low pass

filter for noise reduction in the incoming input signal, particularly for HDTV or SDTV. Applied in the analog domain before

sampling, this filtering removes high frequencies and thus

reduces pixel phase noise (note this also reduces signal bandwidth). Override only if standard pixel tracking and phase adjustments do not adequately clear up a “noisy”

RPMSP & CSP70-D100U User’s Manual 3-23