For all other modes 48Hz, 50Hz and 60Hz refresh rate is available.
3.8.5.
I/O Lock
Available settings: Off, Source, Genlock, Auto
If I/O Lock is switched OFF the output is run with a fixed refresh rate determined by the frame rate
setting. This setting will result in the output vertical refresh rate deviating from the input refresh rate,
even if both are nominally at the same rate. This causes occasional frame dropping or repeat.
If I/O Lock is set to Source the output refresh rate is following the input video refresh rate if possible.
If I/O Lock is set to Genlock the output refresh rate is following the vertical sync of an externally
provided signal (GENLOCK BNC) if locking is possible.
Locking is achieved by modulating the output clock and works if input and output refresh rate are
nominally at the same rate when frame rate is set to 60Hz and the video input is also 60Hz. If the video
input rate is 50 Hz and the Frame rate is set to 60Hz, the output will enter free run mode.
Note: When Frame Rate is set to Auto the matching frame rate is chosen.
When I/O lock is set to Auto and a Genlock source is present to the GENLOCK BNC. The processor will
lock with the external genlock signal if possible. If genlocking is not achievable, locking to the video
source frame rate is tried. If that is not possible the output is running in free-run mode.
The status line of the OSD window under Sync Mode indicates if the output signal is locked to the input
signal (I/O Locked or Genlocked) or in free run mode (Free Run).
3.8.6.
Native Color Temp
Settings: 5500, 6500, 7500, 9300, 10000
Native Color Temp allows the user to select from pre-configured color temperatures to match the
display. If both Native Color Temp set here in the Output menu and Color Temp set in the Color menu
are set to the same value, no conversion is performed.
3.8.7.
Output Gamma
Settings: 1.0 to 3.0 in steps of 0.1
Output gamma allows to re-gamma video signals with pre-configured gamma values to match the
display. Input gamma and output gamma both default to 2.2. If they are both set to the same value,
there is no effect on the image.
Note: If an adjustment to reduce the level of red in the image is required, select a higher number for the
(input) Color Temp in the Color menu, or a lower number for the Native Color Temp in the Output menu.
3.8.8.
Black Crush
For LED videowalls:
Note: The input black level should be optimized prior to using Black Crush and the TNR (and where
applicable MPEG) noise reduction filter settings should also be optimized first. Black Crush is not a
replacement for correct input settings but is available to clean up any remaining black level noise on the
signal which may become apparent on very bright LED videowalls
Settings: 0 to 255 in steps 1
Black Crush provides a coring function on the output stage of the VP-794. This allows low-level noise in
dark areas to be clamped to black which can be useful on LED videowalls on which black level noise
can be particularly noticeable
as ‘sparkles’. It modifies the black response of the gamma & color curves
so as to hide any black-level noise which may be apparent on the LED videowall when high LED
brightness is used, but does this without reducing peak white brightness,
Note this is not the same as adjusting the black level.
