Unlike the USAF, generic color press photos of military subjects were shot with Kodachrome or other chromogenic processes.  These prints have a short archival life and tend to fade or have color-shift problems.  The color in this photo actually ranges from magenta to yellow but has been digitally restored so that the strength of the image can be appreciated.

Click on image to enlarge

Nuclear Testing: "George"

Unattributed, c. 1950
vintage chromogenic print
10″ × 8″