I have some pictures that I took during the day with some friends in city streets, with normal light, in the shadow (not in the direct sun light). Now I want to make them like night pictures. I thought to do as follows, after having obtained the correct levels and white balance on the original image: darken a little, rise the contrast and use filter 80a from photoshop. Maybe the gamma may be lowered a litlle too. Any suggstions?