Underexposing "green" scenes
from a pure technical point of view (and with a Bayer sensor) given that your camera is correctly calibrated for 18% grey (which is not always is unfortunately), there is no reason to underexpose large green patches at all. The argument can only be purely for esthetical reasons or wanted effects.
While I'm not into the technical aspects of digital photography, I think that you've got a point there, and the 'esthetical reasons or wanted effects' part is important for the photography as an art.
As a matter of fact and in some lighting situations I theoretically need to overexpose +1/3 with some of my lenses to get the wanted "correct" exposure. As I am shooting raw I apply the correction in PP if needed. Detail: my cameras have been recalibrated by canon repair on my explicit demand and I stayed with the techies until I was satisfied with the results
Do a quick&dirty check on the camera calibration by making a picture of a 18% grey card and a frame filling green lawn .. your histogram peak should show up at exactly 118 in the luminance histogram, which is slightly on the left of the middle
Understand that. Maybe some day I will try (when I buy a tripod and a grey card )
Thanks and regards
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