Chromatic abberation with white color?

This is somewhat related to the previous topic about magenta and green outlines.
In my case when shooting 600mm VR G with d500 and d850 I'm getting outlines which are mostly visible
with white subjects and especially on cold days. When shooting Northern Harriers now most of the time
white rump will have exhibit chromatic aberration but only with white color.
I was thinking maybe this is heat distortion but I'm not sure.
It usually happens on colder days with f4 and is more visible with 1.4 tc.
Also more visible on shots taken at longer distance to the subject.

Any pointers appreciated. I can also upload pictures if needed.

Thanks

Sounds like CA. This gets better as you stop down so don't shoot wide open if you don't have to and definitely don't shoot wide open with a Nikon TC. This type of CA always looks worst against a very bright or white background. CA also shows up more if you slightly missed focus so make sure focus is properly calibrated.

Just to clear up more. It happens with any background but is visible mostly with white subject.
And halo is of white color unlike regular chromatic aberration.

Andrew_5488 wrote:Just to clear up more. It happens with any background but is visible mostly with white subject.
And halo is of white color unlike regular chromatic aberration.

Oh OK, that is different, which RAW converter and what are your settings for sharpening and shadow/highlight recovery.  This sounds like a processing artifact.  Perhaps post a 100% crop of an affected area.  you can do that by clicking on the little picture icon right above the text entry box.

Here're some examples.Not the best ones but problem is visible.
I had to crop it to fit into 800 pixels restrictions. Pictures are not processed.
Only on export from Lightroom resized to fit 250kb.

I know they're shot at slow speed (metadata included) but I don't think this is a factor.
I also had the same thing with Sigma 300-800 and with Nikon 600mm VR G without teleconverter.

Some people also noticed that:
https://www.flickr.com/groups/393420@N2 ... 784313117/

Interestingly pictures on the bottom of that link are shot with 400mm 2.8.
The only difference is that I usually see that effect more pronounced during winter shooting ( but it happened in summer too).
And since I can't really pinpoint the issue that's why I think it may be heat distortion.
On other hand, wouldn't heat distorion affect bigger area, especially when shooting from distance instead of just a part of the subject?
In pictures below only rump is affected.

Andrew_5488 wrote:Just to clear up more. It happens with any background but is visible mostly with white subject.
And halo is of white color unlike regular chromatic aberration.

What I should say is that halo is white if the subject is white.
If the subject is in different color then halo will have that color but is much less pronounced than white subjects.