I use an old Kodak Duaflex II camera with a cardboard extension, and focus my DSLR lens directly on the Kodak's viewfinder.
I'm sure I look nerdy walking around the desert looking down through this contraption! Anyway, here's what the pics look like using this process. A fairly random group of shots taken as my wife and I were out exploring the 29 Palms, CA, area a few years ago. I'll be taking my "contraption" out soon to take more of these!!
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