8-bit rec709 profiles are much more flexible in post than you might think. I'm not saying they're as good as an Alexa or whatever, but they're a million miles better than people give them credit for.
Here's a latitude and WB torture test of the GX85, in the standard profile (8-bit rec709) customised to have reduced contrast but normal saturation.
For each of the below, the left image is the properly exposed reference image, the middle one is the graded image, and the one on the right is the image SOOC.
Exposure latitude test - +3 stops:
Exposure latitude test - +2 stops:
Exposure latitude test - +1 stops:
Exposure latitude test - -1 stops:
Exposure latitude test - -2 stops:
Exposure latitude test - -3 stops:
Exposure latitude test - -4 stops:
Exposure latitude test - warm:
Exposure latitude test - cool:
Exposure latitude test - magenta:
Exposure latitude test - green (as far as it would go!):
Notes on the testing method:
GX85 shot in manual mode on cloudy day
Exposure varied by changing lens aperture
WB varied by changing colour temp and tint
Tools used in Resolve were mostly Lift/Gamma/Gain, saturation, and some had a bit of Shadows/Mids/Highlights
Notes on the results:
If it's clipped then it's clipped, there's no getting around that
If you've shot a whole sequence in the wrong WB then shoot a test chart replicating the error, spend some time on the correction, then apply to all the shots... a bit of work but worth it to rescue a days shooting
If you've shot on auto-exposure / auto-WB and want to correct the small errors then this is easily possible - it won't have gotten it nearly as wrong as what I have shown above
Most cameras shooting in rec709 will do funky stuff to colours depending on their luma value as part of the look of the profile, so when you over/under expose and then pull things back the hues and saturation levels will have shifted around in odd ways compared to a normal exposure, but if it's a real shoot then you most likely won't have many dominant hues in the image and you only have to correct the ones that are in the frame and distracting, so the above is far more work than normal shooting would be
The days of needing RAW or even LOG to change exposure or WB in post are gone, and although the rec709 profiles often have lower DR than log profiles, they're much better than you think.
If anyone wants me to post full-sized versions with titles so you can flick back and forth then just let me know.
Happy shooting!