Adjusting Grisaille

I’m working on this little portrait for a dear friend of mine. Today I did the grisaille on the skin and I am waiting for this to dry so that I may finish the skin tomorrow. When I had done the grisaille I stepped back and decided that it was too dark around the eyes and I started taking some off with mineral spirits on a brush. This is dangerous work though! The mineral spirits can be unpredictable and it is easy to take off too much. I got lucky today but it’s not recommended – better to put on too little and keep adding than to take off excess.