This is one of the best of the photographs of Mesquite Dunes, as found using Google images. I would guess that a weak-powered telephoto lens, perhaps 150-200 mm was used. I don't think that this type of picture could have been taken with a 50 mm lens or with a 300 mm lens. The artist has certainly mastered this dune field, that is, in realizing that this dune field can only be photographed between sunrise and about 9 am, and between about 3 pm and sunset, and in taking care to keep footprints out of the image. I would guess that this image was taken at the east end of Mesquite Dunes (not the west end), because the east end is filled with flat-faced walls and of Chinese dragon walls that weave back and forth.
TomBrody