I've reached an impasse with at least one or two of the tapes I'm trying to convert. These tapes have a mixture of analog, "VHS import (?)" and/or digital sections on the tape and don't seem to import properly on iMovie. Note I am only trying to capture the analog bits; I don't need to record the film or Digital8 bits (the latter of which were tests and have no content).
For example, one tape has analog recordings made using a non-Digital8 camera, apparently recorded in patches over an old animated film; not sure if that film was on the tape to begin with or it was somehow directly imported onto the tape (it's not simply a recording of a TV playing the film), but anyway, it seems whenever the iMovie recording reaches a part of the tape where it shows the film that was recorded over, the prior bits made using the analog camera are not imported (and neither is the film bit).
Another example involves a mixture of analog and digital. It seems if a tape has both older 8mm and Digital8 bits on it, whenever the iMovie recording reaches a Digital8 point then the prior, older 8mm content is not imported while only the Digital8 part is imported.
I'm guessing in either case it is essentially because the tape has different "formats" on it and the software is designed to successfully import only one format at a time. As imperfect workarounds I have done two things:
1) Stop the iMovie recording before it reaches a bit with the film or Digital8, and resume iMovie recording after said bits. The issues here are that (i) at least a partial second at either edge of the analog bit will not be recorded as I work around the film/Digital8, and (ii) several import files are created instead of just one.
2) Do a screen recording, e.g. using macOS's default Screenshot app, with the microphone volume turned up to max (since direct sound capture doesn't seem possible on this) as the iMovie recording is playing. Obviously this is far from a perfect capture of the picture and sound.
Is there a better way around this such that I can do a straightfoward import without needing the workarounds above (as I can with the other, only-analog tapes), perhaps using different soft/hardware or components? For example, is iMovie or something else to blame? Reminder of what I'm using: Video8/Hi8 tapes in a Digital8 DCR-TRV350 camcorder (which can play older 8mm tapes) importing to a Mac with iMovie using a FireWire400 cable, FireWire400-800 adapter, and FireWire800-Thunderbolt2 adapter. Thanks for any help.