Latticed Window (Fox Talbot)

August 1835, the South Gallery at Lacock Abbey

In August 1835, William Henry Fox Talbot placed sensitized paper inside a small camera obscura and aimed it at an oriel window in the South Gallery of Lacock Abbey, Wiltshire.

The paper was writing paper treated with salt and silver nitrate. Light coming through the window darkened the brightest portions most strongly, so the picture came out tonally reversed.

A negative about the size of a stamp

The result, known as "The Latticed Window," is the earliest known surviving photographic negative. Its image measures 3.6 by 2.8 centimetres.

Talbot inscribed the object "Latticed Window (with the Camera Obscura) August 1835" and recorded that about 200 panes could originally be counted in it with a lens.

How long the exposure ran is not settled: museum accounts range from about half an hour to a possible several hours.

What it was not

This was not the first surviving camera photograph. Nicéphore Niépce produced one around 1826, on a bitumen-coated plate; Talbot's claim is to the earliest surviving negative, which is not the same as the first ever made.

Talbot did not publicly announce his process in 1835. It remained experimental and was developed privately until Daguerre's competing process was announced in 1839.