The work is so bright that when you look at it, you want to close your eyes. With careful strokes, glare, reflections and reflections are “applied” to the water surface. The deep light blue color of the water alternates with the lemon-yellow hues of the sun and small houses standing on the shore.

Started a new canvas; reflected waves in the harbor; red buoy,” Signac briefly noted in his diary entry dated August 22, 1895. The theme of the painting was close to the author from the very beginning, but the artist spent a long time making sketches from the piers in search of a special subject. Several drawings and watercolors allow us to trace the origin of this canvas, which is considered one of his best seascapes. In the background are the facades of houses on the Jean Jaurès embankment in the afternoon sun. Signac, who knew this motif by heart, noted in a lithographic sketch the changing effects of light on the ocher and pink facades. By this time he had already dedicated several canvases this characteristic view of the port of Saint-Tropez, followed by others.

The idea for "The Red Buoy" appears in a watercolor enhanced with ink: the foreground is empty, almost half of the picturesque land is occupied by water, and the brig on the left (truncated in the final version) shows off her elegant rig. The emphasis on red, an important feature of the final composition, appears in an unpublished drawing in a private collection. The scarlet sail enlivens the blue and orange color palette; The artist is interested in reflections on the surface of water. Signac observed the effect produced by a buoy in the harbor and included it in the composition. The evolution of this motif can be traced in three drawings that are now kept in the Louvre Museum in Paris. In this series, the artist quickly explored the buoy in a horizontal format, and then again took up a vertical format centered on the Jean Jaurès quay, accurately depicting the play of reflections created by the buoy at the moment of high tide. The sail, now orange, matches the houses. The emphasis on red, brought to the foreground and attached to the buoy and its reflection, becomes the main motif of the painting. The overall composition was sketched out briefly in an oil study and found its final form in a sketch illustrating a letter sent to Cross at the end of August, in which Signac wrote: "began working on the reflections."