In photography, double exposure is a technique in which a piece of film is exposed twice, to two different images. The resulting photographic image shows the second image superimposed or layered over the first. Using the double exposure technique, you may feel as though your photos have a haunting quality about them, but when done in just the right way, it can also elevate them from photos to beautiful works of art.
Though often created using a manual winding camera, digital photographs can be superimposed by using Photoshop as well. This can be done by altering the opacity of the two images and lining them up over each other. Here's a tutorial called Create Double or Multiple Exposures in Photoshop that will show you how you can create your own multi-layered masterpiece. Also, check out Double Exposure Tips and Photos.
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