The Panasonic Leica DG Macro-Elmarit 45mm f/2.8 ASPH. MEGA O.I.S fits a lot into a very small space – at just about 6.30 cm in diameter, it manages to incorporate both optical image stabilization and true 1:1 macro focusing capability. The short telephoto focal length (equivalent to 90mm on full frame) is also ideal for shooting head-and-shoulders portraits with a flattering perspective.
The lens uses a complex optical design of 14 elements in 10 groups, including an ED glass element to minimize chromatic aberration and (unusually for a macro) an aspheric element. The diaphragm mechanism uses seven rounded blades, to give a circular aperture for smooth rendition of out-of-focus regions of the image. There’s a also a focus limiter switch on the side of the lens barrel, which allows the user to restrict the minimum available distance to 0.5m for faster autofocus when shooting at longer ranges.