Vincent painted the first two portraits in November 1888, shortly after one another. They were painted quickly, with large blocks of colour, bold outlines and broad brushstrokes. The second work feels particularly spontaneous: in places, patches of bare canvas show through the yellow jacket. Vincent only refined the faces, using smaller brushstrokes to add details.
Microscopic research has revealed that Vincent first made a charcoal underdrawing for these two portraits, which could explain why he was able to apply the paint so quickly.
Armand appears to be wearing the same clothes in both portraits, though the jacket is a different colour. It is quite possible that Vincent painted the jacket bright yellow by choice, to achieve a particular colour effect in combination with the background.
He had already used contrasting colours in the first portrait of Armand: the bow around Armand’s neck now appears white, but it was originally more pink – a subtle contrast with the green background. In the first portrait, Vincent experimented with alternating between tranparent and opaque paint. The breast pocket, for instance, is rendered very faintly. Almost as if it has been rubbed off, so as not to distract from Armand’s introspective gaze.
Painting in the evening
The third portrait of Armand is markedly different from the first two. Vincent appears to have painted it in the evening, by gaslight. The painting shares many features with the fourth portrait of Armand's father, Joseph: both have the same flat, bright yellow background, and both show a lack of detail in the hair and face. Armand’s moustache is now rendered as a smudge, with the individual hairs seen in the earlier portraits no longer visible. In the fourth portrait of Joseph Roulin, Vincent treated the beard in a similar way.