What’s the starting frame rate – the frame rate of your edit sequence? Are you trying to slow down the footage? For instance, play 24 fps at 12 fps, thereby, slowing it down by half. If not, I’d expect frames to be dropped to get to 12 fps. Also, I suggest not using QT Conversion. Instead, Export a Self-contained QT and then use Compressor to make your mp4 from that file.
John
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