Having done aerospace instrumentation/telemetry (on a much smaller scale for a private airplane manufacturer), there are some things like separation events, noz

Having done aerospace instrumentation/telemetry (on a much smaller scale for a private airplane manufacturer), there are some things like separation events, nozzle heating patterns etc that can be captured with a single camera which would take many many standalone sensors to capture - that's a lot of money/time saved. The tough part is that video takes a huge amount of the TM bandwidth, so typically you can only send one or maybe two video feeds down, and then you switch between the cameras, as they have done. Actually, realtime video transmission via TM is a very interesting topic, it often uses a specially configured MPEG format. There are a lot of tradeoffs in the parameters that you get to tweak.