The pictures were taken using a standard 18-55mm Nikon lens and an AR-09 - 52mm Adapter ring to inverse the lens.
This isn't the best lens for this purpose by far (its largest aperture is f/3.5 @ 18mm and it doesn't have a ring to set the aperture manually either), but it was worth to take a shot.
Anyway, this technique won't be my favorite one to take macro/close-up photos.
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Don't judge a picture by its thumbnail. Fullview please.