Jack Aeby

Jack W. Aeby (; August 16, 1923 – June 19, 2015) was an American environmental physicist most famous for having taken the only well-exposed color photograph of the first detonation of a nuclear weapon on July 16, 1945, at the Trinity nuclear test site in New Mexico.

On July 16, 1945, Aeby took the only well-exposed color photograph of the first detonation of a nuclear weapon at the Trinity nuclear test site in New Mexico.

The photo was taken with a Perfex 33 with a 35mm lens, using a shutter speed of 1/100 at f4 and Anscochrome color movie stock film.

Aeby was not an official observer at the test site, but was invited along to take informal photos of the work, which he had commonly done since he arrived at Los Alamos. He says he took the photos of the blast on a whim, "it was there so I shot it". He took the film, a non-standard piece of Ansochrome movie stock film, out of the camera that night at a local photo lab, and worked it through the 21 step procedure for color film developing. Later on, Los Alamos management asked him if they could keep the original negative "for safe keeping". It has since been lost.

Aeby says in most uses of the photo it is reversed. This was done intentionally so that the asymmetrical fireball and cloud would look the same as other official pictures taken from the north; Aeby was on the south at the Base Camp when he took the picture.