Some images became icons representing important moments in the past, the little boy in the ghetto of Warsaw, Douglas McArthur returning to the Philippines and Dorothea Lange's picture of despair of the recession of the thirties.
Most people know the original black and white. An important picture and a featured picture on Commons and the English Wikipedia among others. It being in black and white is considered by some as underlining the misery.
This picture can also be found on Commons.. It has been coloured and it gained a different atmosphere. This picture by Dorothea Lange is in the public domain and consequently it is perfectly legal to make this derivative. The provenance is ok; a reference is made to the original at the Library of Congress. But I am in two minds; on the one hand it is a derivative done in good taste, on the other hand it feels like sacriledge..