Check this out
http://www.zvis.com/nuclear/nukimgs.shtml
[ Here are pictures of the most nuclear and thermonuclear atmospheric(or surface) explosions conducted in the period between 1945-1963. On August 5, 1963 limited test ban treaty signed, so all the consequent tests were underground, although there were some exceptions, e.g. China conducted atmospheric tests later. Pictures are grouped by operation names, dimensions and file size shown, almost all of the pictures are color except the ones marked as “bw”. There are mostly US tests pictures in my gallery right now ]