There's a folder "misc/THM/100" on the SD card that has a large number of files taking too much space, they are THM and RVL files. Does anyone know if these files are needed or can I safely delete them to save space.

They are not needed for anything.
You can safely format your card before each flight and start with a clean empty card.

Just format the card in the drone.  It's in the camera menu  Format SD Card

Those folders contain image thumbnails that can be used by some edtining systems, but in the main they are not much use to you.

Thanks for all that replied. I knew we could format the card and fly another day. Just didn't want to delete these if they had any useful purpose.

Labroides Posted at 2016-11-8 18:09
They are not needed for anything.
You can safely format your card before each flight and start with a clean empty card.

/MISC/THM/*.mov files are generated on the fly as soon as a video is recorded.

With my settings (3840x2160 @50), the .mov files are /3 in size and /2 in FPS.
In my case: 1280x720 @25.

They are used when video is played back from the drone to the tablet/mobile in order to reduce bandwith and allow video transmission without jerks.

geohei Posted at 2018-7-7 03:29
/MISC/THM/*.mov files are generated on the fly as soon as a video is recorded.

With my settings (3840x2160 @50), the .mov files are /3 in size and /2 in FPS.

"and allow video transmission without jerks"
That last part could be done more efficient without the need for saving a file and take up card space.

Beside of that was no reason to wake up a thread after 1½ year now there is a fresh one on subject.

Labroides Posted at 2016-11-8 18:09
They are not needed for anything.
You can safely format your card before each flight and start with a clean empty card.

Unless you are flying, several intelligent batteries and recording, with each subsequent flight.

Then only format after downloading your vids and pics. ;-)


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