Xiaomi Yi Exposure Stepping Issues

[Yoolee]

As an owner of the Gopro Hero 3 Black and the Xiaomi Yi (FW 1.12), in my opinion the image quality is very similar. Don't hate me for that, I think both are worth their price.

But here is what I found out:
It happens when there is much light, especially when filming into the sun or when there are much clouds or snow in the image.

On the Gopro in the 1080p60 AND 1080p30 modes there is some slight Exposure stepping, in those situations you definitely can not avoid it.
On the Xiaomi Yi in 1080p60 mode the Exposure stepping is pretty bad.
On the Xiaomi Yi in 1080p30 mode there is no Exposure stepping at all. (That's good, but why????)

In short from worst to best:
Xiaomi Yi 1080p60 bad exposure stepping.
GP3BE 1080p60 exposure stepping.
GP3BE 1080p30 exposure stepping.
Xiaomi Yi 1080p30 no exposure stepping at all.

Xiaomi Yi Examples:

Here Xiaomi Yi exposure stepping starts at 0:30:

Gopro 3 Black Example:

In my opinion this exposure stepping makes a cam look cheap.

Okay you cannot expect a perfect cam for under 100 USD/EUR, but at 1080p30 there is no exposure stepping at all on the Xiaomi Yi (Gopro was not able to achieve that), do you think it is possible to have a 1080p60 Xiaomi Yi without exposure stepping?

 

[Andy_S]

did you try all 3 exposure modes?

 

[Yoolee]

Yes, tried all 3 modes.

 

[Yoolee]

Any ideas?

 

[jessej]

think there might be a command to lock exposure or manually set it

 

[Yoolee]

Sorry couldn't find a solution and I could not find exposure lock. And I wish it worked with auto exposure.

Now I tried the newest firmware 1.1.0.
Tried PAL/NTSC,
tried spot/center/average
tried medium quality.

All with the same result:
no problems on 25/30FPS with 1080p
exposure stepping on 50/60FPS

 

[Photvid]

Modified FW 1.1.0, Z221, no problems on 1080p/60FPS with HOYA NDX16 filter filming into the sun.
Without filter - exposure stepping. I have no idea how to mount filter on camera. I just held it in my hand close to lens.
But anyway image from 1080p/60FPS/30mbps little bit softer than 1080p/30FPS/30mbps.

 

[Andy_S]

That filter just decreases the ammount of light, thus the aperture time will be set to longer one (possibly longest one the camera can handle with still smooth video) and increases ISO = increases noise etc...

 

[Photvid]

For 60fps video exposure must be 1/120s. In sunny day exposure without ND filter is 1/2000s and no noise. I alway use ND filter on Panasonic GH4 filming in sunny day for correct exposure 1/50s, 1/60s or 1/120s. Sorry my bad English.

 

[luckylz]

Before I compared Ambrella A7 & Novatek NT96650 chipset dashcam, I found out that A7 the exposure changing is slower than NT96650.

 

[Yoolee]

Thanks a lot Photvid, that seems to be a good temporarily solution, because as Andy_S wrote, the ND filter decreases the amount of light and the bad exposure stepping only accours in situations when there is much light.

@luckylz:
The exposure changes slower on the A7 chipset, but on lower framerates like (1080) 25/30fps I never saw any exposure stepping.
Could that be a firmware issue, not a chipset issue?

 

[luckylz]

I've no experience using Yi Cam on FPV.
Did you find any handheld exposure stepping, when you use Yi Cam or GoPro3, switching from large amount of lightening changes ?

 

[Yoolee]

Yes, even when filming out of the window directly into the sun, I see exposure stepping on 1080p50/1080p60.
(Currently Fw 1.1.0, high quality, average)

1080p30 WITHOUT exposure stepping:

1080p60 WITH exposure stepping (=looks cheap :-( ):

 

[huhu2207]

Before I compared Ambrella A7 & Novatek NT96650 chipset dashcam, I found out that A7 the exposure changing is slower than NT96650.

Thanks a lot Photvid, that seems to be a good temporarily solution, because as Andy_S wrote, the ND filter decreases the amount of light and the bad exposure stepping only accours in situations when there is much light.

@luckylz:
The exposure changes slower on the A7 chipset, but on lower framerates like (1080) 25/30fps I never saw any exposure stepping.
Could that be a firmware issue, not a chipset issue?

I've no experience using Yi Cam on FPV.
Did you find any handheld exposure stepping, when you use Yi Cam or GoPro3, switching from large amount of lightening changes ?

We have the same problem. My friends have a "808#16" dash camera, which is based on NT96650 and it is made for drones. Also they own a GoPro 3+ black and GoPro 4 black. Compared with the Amberlla-based and Novatek-based cameras, Both of these cameras does have some exposure issues especially when they carried by the drones and rush into the sky, the light environment changes a lot and then the issues will come out. But the amberlla cameras are more “sufficient” to be found out.

 

[Photvid]

Fisrt 10 sec video with ND filter 1080p/60FPS, rest 10 sec without filter https://yadi.sk/i/yGKOUO6IhABra
Download to see in normal quality.

 

[funnel]

Noticed this stepping issue today when driving my bike directly into the sun.

I wonder if one of this two autoexec script commands will have any effect. If somebody wants to try since I don't know when I'll have time.

t ia2 -adj ae disable

or

t ia2 -adj ae 127

or other values from 0-255

 

[JudgeFernandez]

Hey There, Any one found a way to lock the exposure? Im trying to do some 360 work. Thanks

 

[gente]

#fix ae/awb/adj locks
t ia2 -3a 1 1 0 1

or maybe

t ia2 -ae off

 

[JudgeFernandez]

#fix ae/awb/adj locks
t ia2 -3a 1 1 0 1

or maybe

t ia2 -ae off

Thanks but im dont know what that means. Im so sorry. Im kinda new here. Just got my cameras last week. hehehe.

 

[gente]

Thanks but im dont know what that means. Im so sorry. Im kinda new here. Just got my cameras last week. hehehe.

test it for function and what script does what you want, the second one switch off autoexposure, the first one i mean fix autoexposure, autowhitebalance so the stepping is not visible.
Report if it works for you.