This photograph shows more of the room to the right -- and ends at the wall on the right. Here we can see John's bed, only partially covered. But the first thing I noticed is the close proximity of the piano to Sargent's easel. The importance of music in his work and life is quite remarkable; and Sargent's musical talents were pretty substantial.  

Again the painting on the easel is of his sister in The Breakfast Table so this was probably taken roughly the same time, and as the room orientation goes, we are looking just to the right of the view in the thumbnail -- the Madame X painting as been moved.   

Notes
Special thanks to Wendy & Gordon Hawksley Sheffield, England and friends of the JSS Gallery for help finding a better image

• See Boulevard Berthier Studio