NewTek TriCaster 855 - Manual (Page 338)

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For example, suppose a ‘video frame’ supplied by a camera arrives at TriCaster’s inputs one
millisecond after a different frame has been sent to the output. Obviously the new arrival must
wait its turn; it can’t be transmitted until the correct duration for its predecessor has elapsed.
Thus the newly arrived frame must ‘wait’ almost one entire frame, until its turn comes.
How can you achieve the lowest possible latency for the TriCaster section of the IMAG chain?
One trick is to ‘Genlock’ your cameras to the TriCaster output (see Sections 3.6, 3.16 and 7.1.7).
This allows TriCaster to bypass its input time-base correctors, ensuring latency is consistent
during switching operations.
Hint: you can actually assess the latency of your TriCaster installation fairly easily. Run timecode
directly to 1) a monitor and at the same time 2) through the TriCaster to a second (identical)
monitor. Take a photograph that encompasses both monitors, and compare the timecode shown!
B.3.4 OTHER SOURCES OF LATENCY
More often than not, significant latency is added by other devices in the IMAG chain that come
after the TriCaster. Projectors are a common contributor, but at times the cameras themselves
are a factor.
Here are some helpful points to consider when designing and connecting your system:

If you use Multiview output from the TriCaster to the projector -- if at all possible, match
the resolution sent from the TriCaster to the native resolution of the projector. On
some projectors this allows the unit to avoid using its own internal scaling, which is
often a significant factor in unwanted latency.

When possible, try supplying the projector with analog video. This can eliminate a lot of
the complexity from the process (of course, this is not always possible.)

Certain projectors provide a ‘low latency mode’ to disable features of the unit that carry
a heavy toll in latency. Enabling this mode can make positioning the projector slightly
more challenging (as you may sacrifice some ability to position and scale the image
using projector menu functions) -- but the latency reduction can be very worthwhile.