I have recently been flying A2S. Such pink tones appear in the top of the frame and in the lower corners in night photos ?. Here is an example (ISO 100, 2.5s time, MF, manual balance). Photos developed from RAW'a.

It's normal. Sensors do get heated. And the hotter it gets, the more heat noise it shows.  There is a trick that you can continue shooting and after your drone lands, you can cover the lens and take a few black frames using exactly the same exposure settings that you were using. Then you can use these dark frames to subtract heat noise in post.

Sorry for going off-topic, but what place is this? It looks beautiful!

FriedChicken_II Posted at 7-12 04:40
It's normal. Sensors do get heated. And the hotter it gets, the more heat noise it shows.  There is a trick that you can continue shooting and after your drone lands, you can cover the lens and take a few black frames using exactly the same exposure settings that you were using. Then you can use these dark frames to subtract heat noise in post.

And you have your answer!

There is no pink noise at 6s exposure.

Sebi Posted at 7-12 06:25
There is no pink noise at 6s exposure.

Because it depends on TEMPERATURE. You would have to make the camera work long enough to get that pink noise.

Have you tried with a higher iso and seen if the result is the same?

I haven't tried with a higher ISO.