I did a traditional comic style drawing of this battle with the same layout a while back and thought it might look neat to have the movie versions of each manipped into the same poses. Only photos I could use more or less directly were a single shot for the Hulks face and a low-res screen-cap of the things face, the rest of their bodywork was drawn first then I copied over textures from photos (from promo pics for the thing and a few bodybuilders for the Hulk) to flesh them out. Once I had the base for them both sorted out I built up the background from a generic night pic of NY, some rubble, and a few pics of wrecked cars. Last step was to digitally paint over where needed and add lighting/shadowing effects to try and make everything blend in adequately.