Is there any camera with AE Reference (knee) settings

Tehnicni

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I saw AE Reference settings on cheap Aliexpres IP cameras. This setting adjusts the size of the brightest part of the image used for Auto Exposure.
On 4 pictures you can see view through the window in my working room with different AE Reference on IP cam, AE compensation is 0. There is also picture taken with YI Action.
On other camera I found these setting only at Xiaomi YI Action. They call it "Auto knee" and you can set it with script.
Of course, all images are taken in Auto Exposure mode.

I need a camera with this setting to record sunsets time lapse. AE must follow the brightest part of the image near the sun. On a picture you can see sunset recordet with YI, Auto knee 255, AE compensation -1,5.
The problem is that I can't turn off lens shading correction on my Xiaomi YI, so I need other camera or older version of YI..
 

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Tehnicni

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Thanks for response.

In the meantime, I got a 16mm lens from Aliexpress and found that LSC is not a problem at all, it is not noticed.
I sensed another problem, cromatic aberration and the way the camera deals with it.
Apparently it has a correction system that works great with the R and G channels, but with Blue it completely distort the image on sharp transitions.

On a images there is bottom right corner of camera photo, 1 images pixel = camera pixel.

So I think that I need to switch off aberration correction or to change some parameter. Tega seveda ni v Android app, so I need another line in autoexec. Or I have to buy a better lens, this one is 5MP 1/2" for 7€ :)
 

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Tehnicni

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I think that it's not disabled. Look closely at this image https://dashcamtalk.com/forum/attachments/bottomrightcorner-b-jpg.53233/ , this is not a classic chromatic aberration, there are some shadows in the image that are brighter than the white background of the image. It can only result in image processing. If you look RGB picture https://dashcamtalk.com/forum/attachments/bottomrightcorner-rgb-jpg.53231/ , there is no chrom. abberation at smal numbers.
It may be an original lens aberration correction that does not work well on the other lens. If I want to find out what image the lens really gives, I should rule out any corrections.
It’s also weird that the R and G channels are completely consistent, I believe this is the result of a correction in the image processor.
If I used a better lens, the result might be even worse. A correction made for the original lens would further spoil the image.
 
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Tehnicni

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I don't know what you meant.
I know what is CA, at least 40 years.
I think the distortions in blue are due to the action of CA correction.
I don't know the CA correction command, do you?
 
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Tehnicni

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I'm so happy, the lens for 7 € is (as far as CA is concerned) quite OK, I just had to turn off the CA correction. Here is the image of the lower right corner of the image, I don't see any CA.:p:D(y)

Thanks a lot

Now I have to solve the white balance setting for sunset time lapse. If I just turn off auto WB
t ia2 -awb off
the image is not red enough.
We talked about this in this topic https://dashcamtalk.com/forum/threads/update-2-white-balance.19354/ , but did not find a solution.

The next problem is the Edge Enhancement, which I would like to turn off, maybe only when I adjust the focus of the lens. Or maybe permanently and perform EE in post-production.
 

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Tehnicni

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I made a mistake, I thought that t ia2 -adj tidx -1 0 -1 command eliminates sharpening. These is right one:
t is2 -shp mode 0
t is2 -shp cor d:\coring.txt
with 256 x 10 in coring.txt
They also eliminate edge enhancement I thing.

Mode could be
0 - video
1 - fast still
2 - lowISO still
3 - highISO still
so for sunset time lapse with fixed ISO on 100 I must use: t is2 -shp mode 2

I'm not sure about value in coring.txt, is 10 OK for complete removing of sharpening?

So only white balanse for sunset must be solved.
 
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