Examples – 13
VLM-40 NTSC T
ECHNICAL
I
NSTRUCTION
M
ANUAL
OPERATION
P
OOR
C
ONTRAST
COMPOSITE VIDEO LUMINANCE METER
MODEL VLM-40
-48
-40
0
20
40
60
80
100
120
© 1990
SYNC
LUMINANCE
IRE UNITS
-32
SYNC
SETUP
IRE Units
100
80
60
40
20
-20
-40
0
setup = 7.5
Fig. 16. On the VLM-40, the average luminance levels are below 40
IRE and the peak LED indicates peak luminance levels are at 60 IRE.
The waveform monitor shows peak luminance levels just above
60 IRE, but calculating an average luminance level is difficult at best.
For example, there may be white in the picture which will not appear
on the waveform monitor. With the VLM-40, you can safely increase
the overall video level by 10 IRE and still adhere to proper NTSC levels.
