I recently found this awesome old air photo of my hometown:
It's from 1910. I thought it would be cool to see how its looks with colors and gave it a try in photoshop. Thats what i came up with:
[Blocked Image: http://img249.imageshack.us/img249/6904/altenburg1910hl3.jpg]
Like all colorized b&w photos it looks kinda artifical but im happy how some of the colors came out, especialy the trees.
The technique i used was the following: For the basic colors i used a modern air photo as palette. I overpainted everything by hand in a new layer, which i mixed with the original photo. This alone looked very flat and not realistic. For more color variation i rendered different colored clouds in new layers and fiddled around with different mixing techniques till i was happy with the result.