Vidikron VERSION 50 User Manual
Page 43
43
Vidikron Vision Model 50 Owner’s Operating Manual
On-Screen Display Menus
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 on-screen slidebar to set the desired amount of over scan.
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 higher-resolution source, use the HD/RGB Adjust
controls in the Image Option menu, described on page 36.
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 fine-tune the image aspect ratio by stretching it
horizontally or vertically, in small increments. The Horizontal control adjusts the image
width while keeping the height constant. Similarly, the Vertical control adjusts the image
height while keeping the width constant.
This menu item is reserved for future use.
Image Over Scan
Video Black Level
Image Shift
Amplitude
Horizontal Masking
Aperture Control