Using the scene-referred workflow and following the documentation, the exposure module should be used to set the midtones (before adjusting the highlights and shadows with filmic rgb):
Use the exposure slider to adjust the midtones in the image to an appropriate brightness level. At this stage, don’t worry about highlights and shadows – these will be handled later.
How can I determine when the midtones are at an appropriate brightness level? I am using the darktable-elegant-grey theme and have been trying to match the midtones to the roughly 18% gray border around the picture, but I find it is still hard to tell if the photo matches the border or not. For example, here’s an image before I start making any adjustments:
And here are a couple of exposure adjustments:
How can I tell when the midtones are bright enough (and not too bright)? I realize that it is tricky since I am looking at a screen emitting light which will make it look brighter than a print (which is only reflecting light) so I tend to err on the side of making the midtones a bit brighter than I think they probably should be. Does anyone have guidance on how to properly expose the midtones with exposure?
One suggestion someone posted here was to use the channel mixer to quickly convert the photo to black and white to make it easier to compare to the 18% gray border, however even then I find it hard to pick which of the grays in the image I should be comparing to the border:
Thanks for the help!