What is the 4K video file size per minute

[jweaver]

I am just about to order my Mini 2 and am trying to work out my best strategy for SD cards...

What is the average/approximate file size per minute at 4K?

I am not likely to use it for serious application so don't need HUGE storage.. But want something that will give me an hour or 2 of capability.

 

[lannes]

64gb is the way to go, that way it forces you to download files off the card so that you don't loose a lot of data with a flyaway.

 

[Meta4]

What is the average/approximate file size per minute at 4K?

Approx 1.4GB per minute

I am not likely to use it for serious application so don't need HUGE storage.. But want something that will give me an hour or 2 of capability.

No-one needs huge storage on a single card.
You only need cards to store as much of your work as you are prepared to lose in one incident.

 

[jweaver]

64gb is the way to go

Perfect.. Thanks.. Out of curiosity.. How much roughly could you store on a 64G?

Taking my 1080P GoPro, whihc is around 120MB per Min, I am assuming the Mini at 4K would be something like 400MB per Min (total guess)... So on a 64GB would be something like 150mins so 2.5 hours?

Am I in the ball park with these sums?

Edit: Thanks Meta4.. Seems I waws WAY off with my estimate.. So more like 40 mins on a 64G card,.., Still plenty, but I guess I am going to need a few..

 

[jweaver]

The maths doesn't add up... The speed of the SD cards is around 180mb/s... Which is around 20mB/s (Bytes).

This means the max you can write in a minute is 60x20 = 1200Mbytes or 1.2Gbytes. So I can't understand how 1 minute of footage is really 1.4GB...

Are we sure about this? That would max out the card if it were true... And I am not saying its not true.. But don't see how the cards are fast enough to achieve this, as many of the V30/U3 cards out there are only 150-160mb/s, so could only achieve 1.1GB/Minute.

Edit: My colleague just checked his GoPro recording at 4K and that created roughly 10GB files for 30 mins.. So around 400MB per Minute of footage.. Weirdly exactly what I said above which was a total guess.

Could someone not look at their SD and just give a few examples of the size (in MBs) and the length (in Minutes)? And I will do the maths?

 

[NOLADG]

When I did a google search it came up 375 MB per minute and gave me this article: How much 4k video can 64gb hold(It's quite a bit!)

However it really depends on how many frames per second and the bitrate of the drone. The Mini 2 is capable of 4k at 30 fps and a bitrate of 100Mbps.

 

[Dave Maine]

These answers ignore the codec chosen for the video. H265 requires roughly half the space of an H264 encoded video of the same pixel dimensions.

The write speeds of the card have nothing to do with how much data is written. The DJI software controls this, and depends on the setup choices made by the user.

 

[Meta4]

So more like 40 mins on a 64G card

Try 80 mins on a 64 GB card (H264).

 

[PJordan]

My 4K 30fps files as follows:

9 sec = 117MB
1min 59sec = 1.39GB

Guessing you could safely get around 60min of 4K30 on a 64GB card?

Hope this helps.

 

[nathankw]

Max bitrate for the Mini 2 is 100mbps
Divide by 8 to get Megabytes per second = 12.5
Times 60 to get megabytes per minue = 750.

So 750 MB per minute which means a 64GB card can hold about 80 mins (you don't actually get 64 GB available on a card).

That's plenty - more than you'd shoot with 3 full batteries.

 

[MavicAir2Marc]

I used to get around 8 minutes at 4K before the file size limitation (3.75GB) kicked in. That was with my X-Star. I don't usually film sections that long any more, it gets boring pretty fast.

 

[StantonZ]

I happened to have my SD card handy (out of my drone), so I took a quick look.
Recognize there will be differences between H.264/265 encoding as well as bit rates; I tend to use H.265 @30 fps (YMMV).
At those settings, I get ~5 minutes @4k and ~13 minutes @1080p (HD) before the Windows file size limitation kicks in.
For various reasons (some of them legacy hardware compatibility), I don't recommend/use capacities >64 Gig.
Again, for various reasons (including viewing on a 4k TV), I almost always film in HD; I currently have over 30 flights/videos (anywhere from 5-10 minutes in length) on my 64 Gig card...and haven't even used half the capacity.

 

[excalibur1814]

For however long your batteries will last, is how much storage you'll need. Done. Plus, 64Gb is hardly expensive.

 

[DJayI]

A 128GB card came free with my purchase of the Mini 2, but I have been thinking of using a 64GB card to ease the clutter.
I like what Meta4 said about flyaway data loss. Don't want too many eggs in one basket.

 

[netfolks2000]

And remember that you can quickly transfer photos from your drone SD to the phone without pulling the SD card using the Mini 2 quick transfer wireless feature.

 

[Macinfo]

I used to get around 8 minutes at 4K before the file size limitation (3.75GB) kicked in. That was with my X-Star. I don't usually film sections that long any more, it gets boring pretty fast.

Technically the file size limitation is not really a limit, a new file starts immediately and if combined in any video editor, you would not even know that you were looking at multiple files of the same video.