Here’s a fun little Singapore TimeScape project in which I turn two timelapses into single images. Basically what I do is use the technique for startrails to blend images into 1 image. You could easily do this in Photoshop. Use Bridge to select all image, choose Tools > Photoshop > ‘Load Files into Photoshop Layers’. Select all layers, choose Transparency mode Lighten, done.
For an image like this to work, you will need a nice colorful sunset with some movies clouds to create nice streaks. They’re not the easiest scenes to capture, but if you do, you can create some nice ‘cloud stacking’ scenes like this.
There’s a bit more to it than just applying the blending technique, play around with settings and different parts of the timelapse. Results may vary greatly!