For some of you this might be common knowledge but it is a great tip to keep in mind when rendering. If you are constantly rendering with a white background and Photo-shopping the building into a site image or an image of the sky by using that dreadful magic wand or the polygon selector... STOP NOW!
All you have to do it export the rendered image (if it is rendered with a white background) as a .PNG file. Open it in Photoshop and you will see the image has already been cropped and cleaned up and ready for your background image.
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Luke, over at What Revit Wants, dives further into this and explains how exporting to a TIFF file allows for an easy separation between the background and the model elements. This is very useful if you rendered with a background image or a sky, etc...
Click here to check out Luke's post...
