In nineteenth-century France, ready-to-use primed and stretched canvases were available in certain sizes, so-called standard formats. For the different pictorial genres ‒ portrait, landscape, seascape ‒ specific pre-established dimensions were recommended. “After the Luncheon” measures 100.5 by 81.3 cm, and thus corresponds roughly to the standard format “40 Figure”, as we know from comparison with the sales list of a colourman dating from the year 1888. At some time in its past, the canvas was “keyed out” ‒ that is, stretched tighter by adjusting the wedges at the corner joints. That explains why the support is a few millimetres larger than the dimensions specified on the list.