Choosing the shot
Professional wedding photos are usually delivered as large, high-resolution files, so any size works. Ask your photographer for the full-resolution download, not the web gallery version, and check that your package includes print rights; most do.
Two kinds of photos do especially well on metal: bright outdoor portraits, where gloss makes the sky and greenery glow, and dark reception shots with string lights, where metal gives the highlights real sparkle.
Sizes that work
A 16×20 of the couple over a dresser or in an entryway is the classic. For a big formal portrait or the whole wedding party, go to 20×30 or 24×36. An 8×10 of the same photo makes a thank-you gift for parents.
Anniversary gifts
Tenth anniversaries are traditionally tin or aluminum, which makes a metal print an easy, fitting gift. Old wedding photos scanned from prints can work too; send the best scan you can and Trevor will tell you what size it can handle.