Image Over Scan pushes the outside edge of the active picture area of the video signal out beyond the edge of the display area.
Some television programs are produced based on the assumption that older television sets may not display the outer edges of the broadcast picture area. Over scan effectively trims away these inactive, outer edges and enlarges the remaining portion of the image to fill the display area.
Use the
For HDTV, DVDs and other video sources, Over Scan is generally not necessary or desirable.
This control compensates for incoming elevated black levels present in certain video signals, and ensures that blacks in the display are neither “crushed” (where dark grays appear black) nor excessively elevated (where blacks appear dark gray). By default, the projector automatically determines the best setting according to the type of incoming video signal:
•0 IRE – Used for DVD output with “enhanced black,” SECAM, most PAL standards and Japanese NTSC.
•7.5 IRE – Used for most NTSC video signals.
For some types of video, you may want to override the setting. Generally, if black appears crushed when brightness = 30, choose “0 IRE”. If black appears excessively elevated, use “7.5 IRE”.
The Aperture Control lets you control the motorized aperture lens iris. Press the ► arrow to raise contrast and decrease brightness; press the ◄ arrow to lower contrast and increase brightness.
The contrast ratio is the measurement of the difference between the brightest whites and the darkest blacks a display can show. The Aperture Control lets you adjust the contrast level to allow for ambient lighting levels within a room which may affect color detail.
The Image Shift menu allows you to precisely center the image on the screen. (These controls are available only with a 480i source signal.)
Horizontal: This control moves the image right or left within the area of available pixels.
Vertical: This option moves the image up or down within the area of available pixels.
NOTES:
1.To adjust the image position with a 480p or
2.The values shown represent where the approximate center of the image lies in relation to the total number of pixels available horizontally or vertically. This varies widely according to the signal; watch the image while adjusting.
The Amplitude menu allows you to
This menu item is reserved for future use.
Image Over Scan
Video Black Level
Aperture Control
Image Shift
Amplitude
Horizontal Masking
Vidikron Vision Model 50 Owner’s Operating Manual | 43 |
