The base image of Meteora Varlaam for this piece comes from Wikipiedia with a Creative Commons License. Wikipedia has an abundance of high resolution photography that is all licensed perfectly for this sort of treatment.
Before I started this project, I knew nothing about Greece or Meteora Varlaam. I was only searching for the right photo to work on, which is important. However, I did a lot of reading on Wikipedia and I encourage you to read and have fun learning about Greece as I did.
The original image was taken in the natural light of Greece. By layering a darkened, night-time, version of the same image over the top of the original, I could erase the darkened version on top using everything from various masking tools to the eraser tool allowing light to shine in any area or direction I wanted.
Download the Original Hi-Res Version
Taking a photo at night can really plague the image with problems. There usually is not enough light and everything can quickly wash out into blackness. By taking the photo in the day, then converting it to night, I can fake all sorts of light sources, and I can finally illuminate the scene in cool creative ways, however I wish. This is every photographers dream. Since the light sources are made up of the original light captured in Greece, it creates a very natural effect showing all of the underlying textures rather well.
I topped it off by putting some lights inside the windows, adding some 3D rendered light posts on the pathway, and placing 3D generated lamps to help light up the balconies.
It seems like cheating and it is but that is the entire point of Digital Matte Painting. Here is the original image directly from Wikipedia.
Wow, I really need to see Greece some day.