OK I am stupid
This camcorder Sony FDR-AX53 will record in 4K or MP4 format. In other words MP4 can go straIght onto youtube and 4K (more detailed video and clearer) is a bigger file format so can 't. that is the basics anyway.
Now this is where
stupid comes into play. In the video memory side of the camecorder you can have single or dual recording
I had it in dual recording why I didn't know until now or even what it ment. Dual to both formats using up more memory card space or single to MP4 only
when the memory card is in the card reader there is a list of optional routes. one for MP4 and the other for 4K .Something I didn't know and nothing explained in the manual (as usual).
I don't have a 4k monitor at the moment but even so the 4k recording looks a lot better.
Now at least I got it through my thick brain why it is recommended to use a 128 mb memory card for longer recording time
At least Adobe Premier Elements 2020 accepts 4K recording for editing