A painting as a plain JPEG: every object outlined, each opening a side panel of details and film.
The same content as the picture, as text: every part and what it says when you open it.
Its circles and interlaced bands are modelled on the Cosmati pavement before the high altar of Westminster Abbey, the floor on which English monarchs are crowned.
French ambassador to Henry VIII, on his second mission to England in 1533. The painting was made for him.
The gold pendant on his chain is the badge of France's royal order of chivalry: the archangel Michael overcoming the dragon.
Its gilded sheath carries the inscription AET. SVAE 29 - 'in his twenty-ninth year' - which is how the painting records Dinteville's age.
Bishop of Lavaur and Dinteville's close friend, who visited him in London in the spring of 1533. He too served France as an ambassador.
The edge of the book under his elbow reads AETATIS SVAE 25: 'in his twenty-fifth year'.
A globe of the heavens, mapping the stars and constellations. Everything on the upper shelf measures the sky; the shelf below holds the things of the earth.
A cylinder dial for the pocket, a quadrant, and a polyhedral dial with a face for every angle of the sun - instruments for telling the time from the light.
An astronomer's instrument for measuring the positions of the sun, moon and stars, and converting them between the systems of coordinates astronomers used.
A globe of the earth, and on it Polisy - the village in France where Dinteville's château stood.
A merchant's arithmetic, held open with a set square at a page on division.
One of its strings is broken. It is often read as discord - between the old church and the new, or between nations.
A Lutheran hymn book, open at 'Come Holy Ghost' and 'The Ten Commandments' - in a painting made for a Catholic diplomat, in the year Henry VIII broke with Rome.
One of the flutes is missing from its case - another lack of harmony, on the gallery's reading.
An anamorphosis: a skull stretched so far that it reads only from close to the painting's right-hand edge, looking along it. A memento mori - a reminder that everyone dies.
Half hidden behind the green curtain in the top left corner: a silver crucifix, pinned to the curtain and easy to miss.
The picture under this example is the whole painting. Hans Holbein the Younger, The Ambassadors, 1533. Oil on oak, 207 × 209.5 cm. National Gallery, London (NG1314). Public domain; the image is the Google Art Project scan, via Wikimedia Commons.
Paintings and photographs read detail by detail, with galleries and film.
