Precisely because of Veronese’s tendency to reuse and repeat figures, this show has its ups and downs. Although his later religious pictures may be very beautiful, they feel like conventional products of the Counter Reformation. As we know from Veronese’s famous encounter with the Inquisition, he was an artist who needed to give his imagination free rein. If, in a subject like the Adoration of the Magi or the Resurrection, such invention was out of the question, some ineffable connection between the artist and his subject isn’t there. It’s not that he paints on autopilot, like so many Roman painters at this time, but that the creative spark is missing.

But when it’s there, what a painter he is. You see it in his huge altarpiece from the church of San Giorgio in Braida, Verona [above], which shows the patron saint of England in the moments before his martyrdom. The subject is rare in art, so there was no preordained way to show it. I wonder too whether a commission to depict the beheading of an English martyr may have fired the artist’s imagination at a time when Catholic Europe was all too aware that Elizabeth I was about to create new martyrs. Whatever the answer, his performance here is electrifying.

How can an art gallery do justice to a painter who specialised in decorating the walls and ceilings of palaces, and in painting epic banquets so big they dwarf the rooms they are in?

What it must do is what the National Gallery has done for its greatest exhibition since its Leonardo da Vinci blockbuster a few years ago. A whole suite of the gallery's most beautiful rooms, usually filled by its permanent collection, have been cleared so Paolo Veronese's palatial paintings can have the space and light they deserve. The result is an utter joy. Veronese is an artist of abundant, irrepressible life. He is as expansive and theatrical as Shakespeare, who was 24 when the artist died in 1588.

No one knew, for example, that another handy blue, smalt, a by-product of Venice’s glass industry, would leave a gloomy legacy. “Smalt is almost as intense as ultramarine,” explains Salomon. “What no one knew at the time is that after 50 or 100 years, smalt changes colour because it reacts with the linseed oil. When you see an overcast sky in a Veronese painting, you can be sure that it was meant to be blue. This was not known until 15 or 20 years ago. People were praising Veronese’s subtle, grey skies.”

To this chemical reaction add temptation, and the mix can become even muddier. “In some cases, Veronese used all three blues – smalt, azurite and ultramarine. I don’t want to cast any doubt on Veronese himself, but where a patron is paying for a certain amount of ultramarine, he is not to know whether all of that was used in his painting, or whether the artist was able to keep some back ….”