exposure control - frames are coming too dark

[eugenebartosh]

When FPS = 30, frames are significantly dark - adding 75 to each pixel color corrects it more or less. any resolution.
When FPS = 60, frames are very dark, so you can hardly determine details of face. any resolution.
When FPS = 120, frames are absolutely dark, so you can even hardly determine sources of light (lamps, windows). any resolution.
If we can not correct exposure, all the stuff does not make big sense.

Kind Regards,
Eugene