Photograph 51 Showed the World DNA's Double Helix. It Was a Retake.

In May 1952, Rosalind Franklin looked at a new X-ray image of DNA and, that same day, set up the shot again. The second exposure became Photograph 51, the picture that helped three other scientists win a Nobel Prize.

Some accounts have treated Photograph 51 as a throwaway, an experimental image Franklin thought unimportant. An archival study, published Oct. 5 in the Journal of the History of Biology, indicates she knew what she had.

The earlier image was Photograph 49. According to the researchers, Franklin reshot that same sample so the result could be published.

Alistair Sponsel, a science historian at Philadelphia's Science History Institute and a co-author of the study, told Live Science that Franklin was after a sharper, more refined version. Going to that trouble over a sample she had already captured, he said, signals she understood its importance.

That matters because of how the story was first told. In his 1968 memoir, "The Double Helix," James Watson described her photographs as the moment everything clicked, writing that the dark cross in the pattern could only come from a helix. He also implied she was a skilled equipment operator who could not interpret her own data.

Watson, Francis Crick and Maurice Wilkins took the 1962 Nobel Prize in Medicine, honored for the double helix. Franklin died in 1958.

Watson's great revelation came from looking at a photograph. The study suggests the photographer had it first and went back for a better take.

Read the full story at Live Science, October 6, 2026

Hot Take: "The Double Helix" filed Franklin under technical staff. It took 58 years and a history journal to process the reclassification request.