I’m not an expert at changing time bases. Fortunately through luck and planning all my projects have had media with only one time base. From what I’ve read in other threads, don’t just drag your 23.98 file into your 29.97 sequence.
Use Compressor first to turn the 23.98 into 29.97 or vice-versa. In Compressor’s Inspector in the Frame Control turn on the frame controls. Then select best for all settings and let Compressor work. It will take a while. Of course, be sure to select the correct codec and have the frame rate set to 29.97 in the Encoder tab.
There are many posts about doing this and I recommend you check them out for the exact workflow.
John
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