Mark: Yes. I am shooting mainly 2.5K mode 2560x1520, with full stabilizer and geometry correction, so I stayed on firmware 1.1

DrDave: Haven't tested the 24p, sorry.

I suspect the newer firmware limitations may be due to weak batches of Ambarella chips...

I found my next purchase :) https://www.back-bone.ca/product/ribcage-yi-4k-mod-kit/ You're essentially paying about $350 for a camera that takes c-mount (and S-mount) lenses, and shoots 4k at 24p (new firmware update adds this)!

Thanks for the links, Mike. I wonder how well the Protune works at 2.5K and 4K ? That is a primary differentiation IMO. As for the reviewer's comment that the GoPro sound is better, I used the audio from the Yi as my primary feed for mix-down on my last video. 'Perfectly' flat, It sounded great with just a little bass boost and treble peaking, so I am not sure how GoPro could improve on that...

I think with this 3.8mm 16MP lens it can be even better!

@zcream I don't know yet. I didn't get any inform about bitrate from YI Tech.

All I know that is firmware history but there is no inform about bitrate.

@trevmar - I am on 1.1.0 fw, like you, but can't see your "2.5K mode 2560x1520" as mine says in 2.5K mode: 2560x1920 and it's 4:3, not 16:9. Am I missing something..?

Be careful when ordering from GearBest. I waited 15 days and they didn't ship it, and I canceled the order

Did you guys have to refocus the Yi 4K lens? Mine was factory set a bit too close to get sharp on distant objects. Turned it just a bit clockwise and now is fine - from about 60cm to infinity.

@Readbook - as far as I know, Gearbest is the only official online shop for Xiaomi 4K.

Sale for $189 at

http://www.gearbest.com/action-cameras/pp_360137.html?wid=11&utm_source=mail_api&utm_medium=mail&utm_campaign=regular.0207

And Yi 4K has been already hacked - at least the bitrates - that goes up now to 90-150Mbps (instead of 60Mbps).

Significantly better, to my eye. Example:

Valdi99, can I ask you what you see better in that video? I see an over-sharpened image whose field of view is being chopped around as the camera moves (perhaps they have the 'stabilizer' on?). What do you see the higher bit rate is imparting to that image?