Report on the Yi 4K+

[Mark Rosenzweig]

Originally Posted by Bruce Dempsey

fantastic watching on a 4k 27" hp envy monitor and it's quite lovely.
Any focusing or is the depth of field everything out there?
Have you shot any stage stuff with it?

The wide-angle lens ensures a big DOF. See the close-ups of the telescope, with the distant vista still in focus.

No stage stuff yet - the camera does need a lot of light.

[Bruce Dempsey]

Have you defished the footage or is it unaltered?
Most cameras do well in daylight so it will be interesting to see some spotlit stuff

[Mark Rosenzweig]

Originally Posted by Bruce Dempsey

Have you defished the footage or is it unaltered?
Most cameras do well in daylight so it will be interesting to see some spotlit stuff

No alteration in post, except some gamma adjustments.

There is a spot meter mode, which will be very useful for spotlit scenes!

[Mark Rosenzweig]

Yi 4K+ 4K Slow Motion Video: Hudson River Park Strollers and Runners on Vimeo

[Mark Rosenzweig]

Yi 4K+ Cinema Sample on Vimeo

24p, 2:39 aspect ratio, shot flat color and color graded.

[Bruce Dempsey]

I'm wondering if the Yi 4K +1 will employ the DSCRX0 1" sensor?
Have you any indoor footage to show? please and thank you :)

[Mark Rosenzweig]

Originally Posted by Bruce Dempsey

I'm wondering if the Yi 4K +1 will employ the DSCRX0 1" sensor?
Have you any indoor footage to show? please and thank you :)

Here is low-light 4K test footage - shot at 4K24P ISO 800. It was very dark - one light bulb in the ceiling. This was shot to imitate what the scene looked like, not to push to make it brighter than it looked to the naked eye.

Yi 4K+ 4K Low-Light (ISO800) Test Video on Vimeo

[Dave Baker]

Is there any control over the audio level or is it AGC like the GoPros?

[Bruce Dempsey]

thanks, that was illuminating :)
not to shabby at all and quite natural. I could get 2 of these for the price or a RX0

[Mark Rosenzweig]

Originally Posted by Dave Baker

Is there any control over the audio level or is it AGC like the GoPros?

I hate AGC, squashing dynamics and pushing up noise when there are low level sounds. However, in recent years almost all cameras use a limiter rather than aggressive AGC, and it is much better.

The Yi 4K+ allows setting two levels for audio, low and high. High is the "natural" setting. The dynamic range is large, with no pumping. 'Low' is for rock concerts, where the levels are very loud and constant.

At 2:34 in this video, a train passes by. You can hear the incredible dynamic range - from soft to very loud to soft again. That can only happen without aggressive AGC. I can see it on the audio waveform.

YouTube (Short URL)

If you listen to some of the above posted videos with ambient sound, you will also hear large differences in amplitude depending on closeness to subject and subject levels.

[Dave Baker]

Thanks Mark.

I had to ask, we went for a ride on a road "train", a diesel powered mock steam locomotive with a few seated cars behind. I only had the GoPro (Hero 4 Silver) handy, so I used it with the stereo Igomic, which gives better quality audio at a lower level than the cheapies, but as we passed buildings the sound level was pumping like mad. Editing is going to be fun!

I am impressed with both the video and audio from your Yi 4K+, so now I need to decide whether to replace the Hero or do without as I did before.

[Roger Gunkel]

I bought the Yi 4K camera a couple of weeks ago rather than the 4K+ version as I didn't need the extras and the general technical spec was pretty much identical. I am generally pleased with the overall performance of the camera compared with my GoPros and SJ4000s with one exception. Neither my 4K LG tv or my editing system Magix Media Edit Pro 7 will play any of the files from the camera. Magix will normally play absolutely anything and I frequently mix 4K footage from my Panny cams with HD footage. With footage from the Yi, Magix just locks up, although Windows media player will play it. The LG tv comes up with a message that says 'unplayable Format'.

Although the files show as MP4, I don't understand why they are not recognised by Magix or the LG. Has anyone else had this problem with the Yi or can suggest a solution?

Something else I have noticed is that in moderate low light, there is quite heavy graininess/artefacts on any movement. of the subject or the camera. Mark's low light test video is on a totally stationary subject so doesn't show it. It seems to be a common problem with all the action cams, but I expected a bit more from the Sony chip and a 4K spec.

Roger

[Mark Rosenzweig]

Originally Posted by Roger Gunkel

I bought the Yi 4K camera a couple of weeks ago rather than the 4K+ version as I didn't need the extras and the general technical spec was pretty much identical. I am generally pleased with the overall performance of the camera compared with my GoPros and SJ4000s with one exception. Neither my 4K LG tv or my editing system Magix Media Edit Pro 7 will play any of the files from the camera. Magix will normally play absolutely anything and I frequently mix 4K footage from my Panny cams with HD footage. With footage from the Yi, Magix just locks up, although Windows media player will play it. The LG tv comes up with a message that says 'unplayable Format'.

Although the files show as MP4, I don't understand why they are not recognised by Magix or the LG. Has anyone else had this problem with the Yi or can suggest a solution?

Something else I have noticed is that in moderate low light, there is quite heavy graininess/artefacts on any movement. of the subject or the camera. Mark's low light test video is on a totally stationary subject so doesn't show it. It seems to be a common problem with all the action cams, but I expected a bit more from the Sony chip and a 4K spec.

Roger

This is an odd post in a thread labeled and devoted to the 4K+. The 4K+ has a processor that is twice as powerful as the one in the camera you are posting about. That is relevant not only to the ability to shoot 4K60p, which your camera cannot, but also to low light IQ, since low-light video undergoes noise-reduction processing - that is very processor intensive. So, we cannot know whether what you are seeing in terms of artifacts in low light is the result of having a processor that is too weak, a processor that is similar in power to all action cams that have come out prior to the 4K+.

[Roger Gunkel]

Originally Posted by Mark Rosenzweig

This is an odd post in a thread labeled and devoted to the 4K+. The 4K+ has a processor that is twice as powerful as the one in the camera you are posting about. That is relevant not only to the ability to shoot 4K60p, which your camera cannot, but also to low light IQ, since low-light video undergoes noise-reduction processing - that is very processor intensive. So, we cannot know whether what you are seeing in terms of artifacts in low light is the result of having a processor that is too weak, a processor that is similar in power to all action cams that have come out prior to the 4K+.

Sorry to make an odd post on your thread Mark I thought there might be some advice available but my bad! I'll disappear and wear sackcloth :-)

Roger

[Mark Rosenzweig]

YouTube (Short URL)

On the Zhiyun Evolution gimbal.