I know that the 8 supports 4K UHD video recording, but how many frames per second does it record? Or, more accurately (because I don't know how many bits per pixel it records), does anyone know the bitrate that it records 4K UHD at?
Basically I would like to know if I can use a UHS class U1 microSD card in the 8, or if it really needs a UHS class U3 card.
After a bit more digging I found some answers here on the forums and on the tinterweb.
4K UHD is at 30fps, 42Mbps
1080p is at 30 fps, 20Mbps though apparently the recording is sharper than 4K
Slow motion is 720p at 120fps (I think). I couldn't find a spec for the bitrate so I did a recording to calculate it. I think it's ~126Mbps! I recorded an ~11second slow motion video and the video itself lasts ~34s and takes up 173MB. 173MB/11s * 8 (bits per byte) = 126.
I checked the file in VLC and the playback is 720p 30fps with a bitrate of ~42Mbps. So, given that the video lasts 3 times as long as I recorded it for, means the actual recording bitrate was 3x faster, therefore ~ 126Mbps is about right!
If anyone knows better and correct my logic please join in!
Summary: I think a UHS class U1 card will be sufficient. Probably ;)
Well, at first I thought I needed a U3 card, but after looking at the bitrates I didn't really understand why. The 4K UHD recording on the Nokia 8 is only 30 fps, only 42Mbps, which is ~6MB/s, therefore U1 should be fine.
What surprised me is that the slow-motion recording was a higher bit rate, ~15MB/s. For this, I should have a U3.
FYI this is what I bought: https://www.integralmemory.com/product/ultimapro-sdhc-sdxc-80mb-class-10-uhs-i-u1-memory-card
I'll see how I get on and if I notice any problems I'll post feedback here.