User`s guide

SMPTE .
-?
B.4 TIME DISCREPANCIES
Real time is defined as the time elapsed
during the scanning of
60 fields (or any
multiple thereof) in an ideal television
system at a vertical field rate of
exactly
60 fields per second.
Color time is defined as the time
elapsed during the scanning of
60 fields
(or any multiple thereof) in a color
television system at a vertical field
rate of approximately
59.94 fields per
second.
'7 Because the vertical field rate of a
color signal is approximately
59.94
fields per second, straightforward
counting at 30 frames per second (60
fields per second) will yield
an' error
of
+I08 frames (+216 fields), equivalent
to
+3.6 seconds timing error, in one
hour of running time. For correction of
this time discrepancy, two methods of
operation are allowed:
Nondrop Frame During a continuous
Uncompensated Mode recording, no
numbers shall be
omitted from the
chain of addresses.