different exposures in the same flight

That's a white balance problem.  You need to set it manually in the map pilot app to sunny or cloud.

Thank you, that was helpful. What I don't understand is why the Auto feature didn't work properly, when I looked in my settings, Auto was selected.

The Auto setting was working properly but what the automatic white balance is doing behind the scenes is making a judgement on the illumination level and adjusts it on the fly. White balance is adjusting for the spectral content of the incident light. Sunny conditions are redder light and cloudy conditions are bluer. The end goal is to make a white things look white but it doesn't always work out perfectly.

If you fly over a brighter area of ground it will think it is getting sunny and switch to the sunny setting. If you go over a darker spot on the ground it will switch to cloudy.