I'll try to be articulate this time. Look at the shadow on the girl's cheek indoors vs. the shadow on the girl's cheek outdoors. On the indoor cheek, the color is very greyed out on my screen, and very mauve/chalky. I don't have a value scale in front of me, but I suspect the darks here are only at about 4 or 5. The outdoor cheek shows color that is much more saturated, not chalky or greyed down.
As for tonality - the outdoor photos seem to have a broader tonal range, which helps flesh out your paintings. Here's a link to a Kramskoi portrait on this forum
http://forum.portraitartist.com/show...light=kramskoi (you may have to scroll down to see it) -- while I do not feel its necessary to have a wholly dark portrait with only the face lit, I do notice that in my work, if I don't use a large value range, the work stays too flat.
In other words I notice a distinct "palette" in your indoor photography. My last comment about the camera not being so "objective" after all refers to the fact that your photos have a very distinct voice -- someone could pick them out of a pile and assign them to you, it is your handwriting, very unique. Your recent painting of Victoria (I think I'm remembering correctly) shows this same beautiful color scheme. Was the light in the Caribbean the same as the light in your dining room?
My only relevant observation is that you might want to explore a broader range of tonality in preliminary sketches. Most of your values seem clumped from 1 to 4 or 5. I'm not suggesting you change anything, but you might be interested in your results, if you shake it up a little.