The cheapest and easy accessory for macro to carry around, because they work more like a filter - can be screwed directly into the front thread of your lenses. It is a simple, convenient way to increase magnification. Even when attached, you can still use automatic exposure control and TTL metering with all those F2 metered prisms. Most of these lenses have been treated with Nikon Integrated Coating to improve image contrast and reduce flare. Well, there are many third party offerings as well, and if price is a main factor to consider, you can take a look at those alternatives as well.