Recorded a flight today, or at least I thought I did 
but there was nothing on the SD. There seemed to be some and a few photos but I think that’s what was cached as opposed to saved on the SD.
I did forget to format the SD 
could this be the reason?
Also when you do a recording is there anything I should to to ensure it saves to the SD as opposed to caching it.
Sounds like an app cache issue. What are your video settings and what card are you using.
So did I do anything wrong or is it something in the app I need to change?
I have been through the settings, couldn’t see anything obvious I may have missed.
On your SD card when you view it on a Mac/PC you will see two folders, one of these is the low res cached files. You can clear these by formatting or doing a video cache clear on the Go4 app.
When I viewed it on the PC, would even open it said something like format not recognised…
So put it back in the MP, and what I could veiw is what I think was cached. I then formatted the SD in MP, then put it back in the PC which then let me open a folder on the SD, obviously empty though.
Which makes me think It was because I didn’t format the SD?
Yes formatting does seam to be the issue here. I pull off the media I want on the Mac then put the card back into the Mavic then format. Trouble free so far.
Thought that would have been the issue here, schoolboy error!
Gutted as it was my first Long distance flight, well long for me 1k out, then went across 500m and returned the 1k.
I am right in that I don’t need to do anything to make it save to the SD?
No it will always save to the SD card.
Sounds like what you were viewing here was actually cached on the device you fly with (phone / tablet), rather than cached on the Mavic as such.
As a test, launch GO4 without even powering up the drone, if you can still view the footage then you’re definitely looking at something locally cached 
Interesting!
I formatted my card in the Mavic the day I got it, but I’ve never formatted it since.
I ‘move’ the videos/photos off the card, but never reformat it.
Does reformatting not reset the filename counters back to the beginning again?
Yep, you’re right Rich. Just checked, I’m able to veiw them on my phone.
What device do you fly with, Jon?
I’m thinking a copy of low res cached footage may be better than no footage at all?
IPhone X but it’d seem it cache the flight I was after, possibly it was full.
It’s possable the card became full and dumped it local. Was this footage near the end of your filming for the day?
Hmm!
Depending on your cache size settings (which you can change btw ) it would always dump older media to make way for the new.
If you are recording while flying, then you land your drone and turn it off without stopping the recording, your file on the SD card come corrupted and you can not view it on your sd card. But you can view it on the app from the cache
Yep. I made that mistake!
i actually format card before every flight so i know its empty