I don’t think it works like that.
In black hot those cameras usually show:
- full black: the hottest point in the scene
- full white: the coldest point in the scene
All other values of gray are in between values of IR radiation in the scene.
As the camera pans quickly the scene shown to the operator adjusts depending on the hottest and coldest point measured by the sensor in that specific instant/frame.
It is probably automatic in this scene but we can’t rule out some manual adjustments on top of it.
I'll explain. I'm an old film guy. Photo major and advanced amateur in film photography. Not laying the ground for an argument from my own authority, but laying the ground to explain why I think this is (at least primarily) a change in brightness and a manual adjustment.
When you increase brightness
everything in the frame gets lighter.
When you decrease brightness everything in the frame gets darker.
All values change together and equally
Contrast increases or decreases the differences between dark and light values.
After you've made a few hundred prints off different negatives you get an eye for the difference between brightness and contrast and what needs to be adjusted. Keeping in mind that I'm rusty, I'm fallible, and I don't know much about this IR digital system,
to me it looks as if it's brightness that's being adjusted in this GIF, which goes from 0:08 to 0:11 seconds in the high quality video.
Note that all values are changing from lighter to darker. The UAP gets darker, the ground gets darker, even the artifacts get darker. What I see is the brightness getting turned down. Quickly and a lot.
If contrast alone were being increased, the UAP balloon would be getting whiter, not darker, while the dark areas would be getting darker. If contrast alone were being decreased, the dark areas in the background would be turning gray, not darker. We don't see either of these things happening. Everything is getting darker. To my fallible eye this is the brightness getting turned down, rather drastically.
Now then, contrast may also be changing at the same time. This system may link the two together in some complex way, even when in manual mode. But I can't
see that. I fully acknowledge that this may be my failure. It may be that I can't keep track of brightness and contrast at the same time. It may turn out that the contrast is being adjusted up or down at the same time... or not at all.
To complicate further, there's the question of dynamic range and perception. Dynamic range is the range of bright and dark values that something can record/perceive/display. Over exposing or under exposing film degrades the dynamic range of the film and degrades the contrast in the image. Is the same true for this IR sensor? Don't know.
Does adjusting the brightness in this system involve changing the amount of IR light getting to the sensor? (Adjusting the size of the iris in the diaphragm of the camera lens?) Or is it an electronic adjustment? Don't know.
Also human perception of values can change. So maybe this IR system makes changes in contrast to compensate? Don't know. But in that case the whole point in changing contrast would be so that you
wouldn't see a change in contrast.
Turning to the question of whether this adjustment in brightness was done by the operator manually, or whether this is an automatic adjustment...
Luminance indicates the brightness of light emitted from or reflected off a surface.
This is what I see:
The luminance of the background is not changing significantly during this ~3 seconds of the video. And we can safely say that the luminance of the UAP isn't changing either.
So why would the auto-brightness feature (it would be auto-exposure on a film camera) make an adjustment to the brightness when there's no change in the luminance within the frame?
Because the bootleg camera didn't capture the entire video screen, we can't tell for sure whether brightness and/or contrast were set to auto or manual.
I'm just reporting what I see. An informed - but fallible - speculation. To me this looks like a manual change in brightness by an operator testing to see if that would help him to recognize what the heck he's looking at. It doesn't matter if that test made it look crappier for a few seconds. It was an experiment. Experiments can fail.
It's already been established that the object was being manually tracked by an operator, so we can reasonably assume that the operator may have been doing other things. Like adjusting brightness manually. That's what I would do.