A lens of 2-element, 2-group construction and a +10 diopter rating. Resolution is outstanding and focusing is possible at 10cm for super close-ups of insects, flowers and other small objects.
The magnification is about 1:2 with a 50mm standard lens (35mm camera), roughly equivalents to a 100mm telephoto lens. The lens should be stopped down as much as possible to get maximum depth-of-field.
In order to avoid purchasing one of those counterfeit filters we highly recommend to purchase only from official retailers that are recognized by HOYA's official global distributors. Prior the purchase kindly inquire and verify whether a retailer is authorized by HOYA global distributors. You may find the contact in the HOYA global distributors list.