If you are experiencing MTS clips no longer working with Premiere CC 2018 issue, you may wish to read this post. It displays a workaround to get PPro CC 2018 working well with AVCHD MTS files.
Importing issues regarding to MTS clips and Premiere CC 2018
“I installed the Premiere CC 2018 version and when importing AVCHD clips (via media browser) no audio tracks where recognized. Emptied my cache. Tried re-importing the files. No luck at all. The MTS files are still “media missing.” Any suggestions?”
“So, I just upgraded to Windows 10 Professional. Tried opening my project in PPro CC 2018… Unfortunately, Premiere CC 2018 wasn’t dealing with my MTS files at all. The audio would not display. I tried various fixes, with no luck. In the 2017 version (runs parallel) the import works without any problems. Any fixes?”
The solution from Adobe Stuff
“Both Windows and OS X operating systems (Windows 8.1 or above and Mac OS X .11 or above) contain native support for Dolby decoding functions. Please update to the latest version of your operating system.”
Unfortunately, this didn’t solve all the AVCHD audio lost issues in Premiere CC 2018. Some users have reported that they are already running the latest Windows 10 or macOS High Sierra 10.13, and the problem persists. If that’s the case, we would recommend transcoding AVCHD MTS files to ProRes or DNxHD before editing for a smooth workflow in CC 2018. Check out a guide on this.
How to convert AVCHD MTS files for use in Premiere CC 2018 flawlessly?
Step 1: Start up HD Video Converter as an AVCHD MTS to Premiere Pro Converter.
Step 2: Click ‘Add File’ to import your source media to the program.
Step 3: Select output format
* If you are on a Windows PC, from the “Profile” bar, choose ‘Avid DNxHD 1080p (*.mov)’ as output under ‘Avid Media Composer’ column. (See the screenshot above)
** If you are on a Mac computer, choose ‘Apple ProRes 422 (*.mov)’ as target under ‘Final Cut Pro’ catalogue.
Step 4: Custom video and audio settings (for advanced users)
Click ‘Settings’ button, the ‘Profile Settings’ panel pops up, on which you are able to modify video and audio settings like resolution, bit rate, frame rate, sample rate and audio channel.
Step 5: When ready, click ‘Convert’ to start transcoding AVCHD MTS files to Premiere Pro 2018 supported QuickTime MOV format. As soon as the conversion is complete, click ‘Open Folder’ button to locate the generated files and now you are able to open them in Premiere Pro for further editing smoothly.
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