Mirrors are fun and easy to create in Photoshop. Just hit Crtl+J to duplicate the Background layer, Transform flip horizontal or vertical, use the Crop tool with nothing in the Option bar to double the size of the canvass. (Yes, the Crop tool can increase as well as decrease canvass size. Just draw a crop boundary around the whole image and drag one side in the direction you want.) Now select the Move tool, hold Shift and drag the top layer to the side or up or down as appropriate. If you wish you can flatten the image and do it again in the other direction.
Here is a photo from the new prayer hall at Khari Gompa in Thamo, Khumbu, Nepal. The spiritual head of this nunnery for Tibetan refugees is my good friend Khari Rinpoche.
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