Ingres Madame LeBlanc WIP

Here is a detail study of Ingres' Madame LeBlanc. It is still a work in progress, but the tonal study was pretty enlightening! All comments and suggestions are appreciated, and any suggestions on how to proceed are also appreciated.

I did the tonal study as practice, intending to use it as a guide for the overpainting, but not as a glazing underpainting; it's not that smooth.

Thanks!

Oh, honestly!

Ivory black and titanium white, scrubbed in, with a bit of burnt umber in the background so I wouldn't yet lose the edges.

This image is cropped. I got it from www.artchive.com (Thank you Peter Jochems for introducing me to that site!).