Did all three cameras match? All were the same codec? This was HDV or? HD 1080 comes in a bunch of flavors actually, could be HDV, or XDCAMHD or another half dozen flavors, and in order to use multiclips without problems, is to make all the video be using the same codec.
If you had to render in the end and didn’t have any filters involved, then the sequence settings didn’t match the clip’s properties. You should only have to render if you add a filter.
As a side note: The broadcast safe filter isn’t the best way to make it safe either. Color correction does a much better job of preserving the images and making them legal. Broadcast safe just clamps what’s illegal and loses the detail in those areas when it is applied. (which in some cases doesn’t matter, but usually it does). Japanese cameras over expose everything if you use automatic exposure settings too. It’s much better to use a waveform monitor or light meter to expose correctly in the first place – not needing to make them safe per se, but using color correction to bring out the richness that video cameras just can’t seem to maintain. Makes a world of difference IMHO. But I’m digressing a bit.
Jerry
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