Panasonic Lumix G 42.5mm f/1.7 ASPH. Lens Now In Stock May 25, 2015 By Eric Reagan B&H has the new Panasonic Lumix G 42.5mm f/1.7 ASPH. Power OIS lens in stock and now shipping. That’s a 90mm equivalent focal length, which should make for a nice portrait lens for Micro Four Thirds shooters. Check it out here at B&H Photo.