When he translated his reference photo into a painting, Andrew Loomis softened the edges and subordinated the unimportant small forms. For example, he simplified the details under the model’s left hand, and eliminated the delicate tracery in the lower half of the dress.
To idealize the figure, he made the head of the model slightly smaller in the painting than it appeared in the reference.
He was also conscious of breaking up the flat tones of the photo.
“One of the main things that identify a photo as a photo,” he wrote in his classic book Creative Illustration, “is the ultra-smoothness of the tones.”
Where the photo presented monotonous values, such as in the pillows behind the model’s shoulders, he activated the surface with painterly variations.
“Note the accents placed here and here of dark against light, to add punch,” Loomis says. “The lights have been forced somewhat to obtain extra brilliancy. The background has been lightened in spots to avoid the monotony of tone in the photo.”
From Creative Illustration (1947)