Extron Electronics VN-Matrix 200 Series - Manual (Page 66)

NOTE: A stable video signal on the loop output of the VN-Matrix encoder does
not necessarily indicate that the signal is being properly recognized
since a VN-Matrix encoder generates the loop output signal by passing
sync directly from the input connector to the output connectors (a
passthrough), so it is not dependent on any previously stored modes to
create a loop output.
TIP: A word about active image detection
Before creating the custom mode, be aware that VN-Matrix may report
inaccurate values for active horizontal pixels (digHSize) and active vertical lines
(digVSize).
VN-Matrix analyzes the content displayed by the source PC to determine
these values. As a result, if your source is displaying a 100 pixel by 100 pixel
white box against a black background, VN-Matrix may report a digHSize value
of 100, and a digVSize value of 100 as well.
Given this fact, it is good practice to ensure that your PC is displaying a full
image, preferably full white or a moiré pattern, before creating a custom
input mode.
VN-Matrix 200 Series • Advanced Setup Procedures 61