Here's a short tutorial and idea guide about how to create the effect of one photo spanning across multiple layers in Photoshop.
You can use a template, like I did in the layout below. I used a photo template by Dawn Inskip that contains 3 stacked photo masks, 3 borders, and a ripped edge, each with individual drop shadows. To retain the shadowing, ripped layer, and borders, duplicate the same photo, without repositioning it (in Photoshop, hit Cmd J on the highlighted layer), and clip each photo to the respective photo layer (making sure not to move the photo up, down, or side-to-side on the page -- Photoshop shortcut Opt+Cmd+G). If you're satisfied with the results, you can simply merge the layers together when you are finished (Cmd+E).
Wendy also has an action that will stack a single photo, which has a subtle effect, similar to the first layout above.
Another simple but eye-catching way to span photos across two frames is just to mask off portions of the photo behind a double-frame element, and combine it with two different views of the same image. That's exactly what I did in this page, below. I added a layer mask to the photo, and using a brush, painted black on the mask to hide portions of the image. In addition, I used a sketch action on the same photo, and placed it beneath the framed picture. I kept both the sketched image and the photograph the same size / scale, so they were easy to layer seamlessly one on top of the other.
|WendyZine SketchIt action, Studio Digilicious Travelbug kit|