AVCHD conversion to mp4

https://handbrake.fr/docs/en/latest/technical/source-formats.html says it can handle AVCHD but not if spread across multiple files.

Any conversion to mp4 will involve quality loss. I am not familiar with iMovie 10 but I believe older iMovies converted a file to AIC which was also lossy though not horribly so. If this is the same for your iMovie 10 then just remember you'll be going AVCHD --> MP4 --> AIC --> MP4 (or whatever) so there will be 3 quality loss steps. I can't think of any other solution using iMovie though. You'd either have to go for higher end software or see if some of the free movie software (kind of steep learning curves from when I have looked at them) can handle AVCHD source files.

My problem is related though different and the solution Apple provided might help anyone out there who is experiencing a "glitch/picture break up" in iMovie. Here are more details from my earlier post in the SD card reader not working forum:

I had a similar problem but with an important variation. I COULD import footage from my SD card - no problem there - but when I created any movies in iMovie after the beginning of November 2017 there was a noticeable defect/glitch/picture break up at the top of the frame which lasted a second or so. This occurred several times in a 3 or 4 minute video. I considered problems with my camera or the SD card or the slot on my Mac but then realized that the problem occurred RIGHT after upgrading to macOS High Sierra 10.13.1 in November 2017. IMHO then it had to be related to the upgrade and after discussion with techs and Apple Care, I learned it was a combination of the upgrade AND the fact that my regular camera model was no longer supported by Apple and iMovie. Big news to me. Tim at Apple created a "walk around" for me that meant I would not need to go out and buy a new camera. Basically it involved on finding the clips in Canon then AVCHD and then exporting via Quick time and them importing back again as a .mov file. A little convoluted but it has been working. So if anyone is having that "glitch" problem - no need to buy a new camera - just take this new approach. Hope it works for you as it did me

Hi, Limnos,

You raise some good points.

I think that whatever loss there may be probably wouldn't be significant or visible to the eye to most people for movie purposes. Anyway, there's no choice. The path would be MTS>Mp4>iMovie 10>Mp4 (or .mov if share by Best Quality pro res). I don't think that iMovie 10 uses AIC any more, though that codec is compatible.

Best,

Rich

Hi, pierre,

The free download, Handbrake, works very well to convert files to Mp4. Many people who contribute to this forum use it.

-- Rich