Recommended SD card for new 3E

[PhantomFlyer3SE]

Do us all a favour and report back with the size of one of your 4K video files, including the total recording time.

Are you formatting 32+ gig cards as exFAT?

I tried different formattings because of 4GByte block limit, but on the SE formatting has no effect even on the block size limit, even on the write speed.

The problem is not with the avarge writing speed, with is much less as apex. Usual the recordig time of 4GByte block is about 5-6 minute, which means ~10MB/sec avarge data rate.

 

[With The Birds]

I tried different formattings because of 4GByte block limit, but on the SE formatting has no effect even on the block size liment, even on the write speed.

The problem is not with the avarge writing speed, with is much less as apex. Usual the recordig time of 4GByte block is about 5-6 minute, which means ~10MB/sec avarge data rate.

The 4gig limit isn’t a fat32 file system limitation, it is the AVI file structure (32bit addressing provides 2 to power of 32 which is 4,294,967,296 bytes- 4 gig as max).

4 gig should be giving you around 8 mins of footage @ 4K...

 

[PhantomFlyer3SE]

The 4gig limit isn’t a fat32 file system limitation, it is the AVI file structure (32bit addressing provides 2 to power of 32 which is 4,294,967,296 bytes- 4 gig as max).

4 gig should be giving you around 8 mins of footage @ 4K...

If your recordig with your Pro was 8 mins, it means that at this recording the avarage data transfer speed was more then 8 MBs. The peak is a multiple of this. If you doesn't have any issue, then if you will measure your cards write speed cabability, you will get a value over the requirement of Class 10.

My first try was a Kingston 64 GB UHS-1 card, its write speed capablity was 25-27 MBs, which is good for 2.7K, but not for 4K

 

[With The Birds]

If your recordig with your Pro was 8 mins, it means that at this recording the avarage data transfer speed was more then 8 MBs. The peak is a multiple of this. If you doesn't have any issue, then if you will measure your cards write speed cabability, you will get a value over the requirement of Class 10.

My first try was a Kingston 64 GB UHS-1 card, its write speed capablity was 25-27 MBs, which is good for 2.7K, but not for 4K

I still suspect if the card was capable of 25+ MB/s you wouldn’t have had an issue. I had a quick look at the Kingston website, interestingly not all the UHS 1 cards are marketed as suitable for 4K.

DJI’s claim of 60Mbs for the P3SE seems correct based on recorded file sizes. It might be as you say that on occasion the data is written to the card above this rate- there is 64MB of DDR ram on the P3 camera to allow for buffering.

 

[PhantomFlyer3SE]

I still suspect if the card was capable of 25+ MB/s you wouldn’t have had an issue. I had a quick look at the Kingston website, interestingly not all the UHS 1 cards are marketed as suitable for 4K.

DJI’s claim of 60Mbs for the P3SE seems correct based on recorded file sizes. It might be as you say that on occasion the data is written to the card above this rate- there is 64MB of DDR ram on the P3 camera to allow for buffering.

Source of figures:
Speed Class Standards for Video Recording - SD Association

The fact is, that with P3SE the UHS-1 card with measured 27MBs write speed has many frame drops.
UHS-3 card with measured 40MBs write speed is a lot better, but if camera turns, or fly on low altitude recording has frame drops as well.
(These are the scenarios, where the picture change dinamically, and data compression become less effective)
Of course cache can hide this changes as long it is not full. But when it is full the effect is really annoying, parts are deleted from cache, picture has big jumps.

Based on recorded file sizes it's clear, that DJI's claim is wrong. If you do the matematic (one minute has 60 secons )
even the average data speed is over 60Mbit/sec.

Based on my experience my promise to other P3SE owners is to buy sd card with capablity to 60MByte/s write speed, if they want to record good quality 4K videos.

 

[With The Birds]

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Source of figures:
Speed Class Standards for Video Recording - SD Association

The fact is, that with P3SE the UHS-1 card with measured 27MBs write speed has many frame drops.
UHS-3 card with measured 40MBs write speed is a lot better, but if camera turns, or fly on low altitude recording has frame drops as well.
(These are the scenarios, where the picture change dinamically, and data compression become less effective)
Of course cache can hide this changes as long it is not full. But when it is full the effect is really annoying, parts are deleted from cache, picture has big jumps.

Based on recorded file sizes it clear, that DJI's claim is wrong. If you do the matematic (one minute has 60 secons )
even the avarge data speed is over 60Mbit/sec.

Based on my experience my promise to other P3SE owners is to buy sd card with capablity to 60MBs write speed, if they want to record good quality 4K videos.

According to your chart posted UHS 1 class 10 is adequate and for many (me included) no issues are experienced. I don’t do 4K at 60fps so perhaps that might reveal an issue. The caveat might be cards that only just qualify as UHS 1 might struggle (as you claim happened with the Kingston). I very much doubt the P3 SE exceeds 60 Mbits max data rate- DJI would say if it did. More is better.