My Favorite Lens? Currently My 70-300mm Nikkor f/5.6 Zoom
One of the most fun things about owning a DSLR, of course, is that there are so many lenses available. In fact, photographers (pros and amateurs) probably spend more time fantasizing about owning newer and better lenses than actually using them. It's easy to become addicted to the visual possibilities of owning a lot of lenses. I've owned a lot of lenses over the years, but I have sold a few lately on Ebay, so don't have as many as I usually have. One of the reasons is that I want to upgrade several of my older lenses to image-stabilized lenses and I wanted to sell my non-IS lenses while there was still a market for them.
No matter which lenses come and go though, there are a few that just become my favorite go-to lenses and currently (and for the past few years) one of those has been my Nikon 70-300mm f/4.5-5.6G ED IF AF-S VR Nikkor Zoom Lens for Nikon Digital SLR Cameras. For around $500 it's one of the best lenses I've ever used. Yes, it's a bit slow in terms of maximum aperture, but compared to the $2,000 80-200mm f/2.8 Nikkor (which, admittedly, was a sharper lens and had a constant maximum aperture but you're talking a lens that costs two grand!) that I used to carry everywhere, it's much lighter (I can carry it in my photo vest pocket easily) and it's perfect for using in nightclubs and theaters when I'm shooting concerts. I sometimes sneak it into theaters in the inside pocket of my denim jacket.
There is just something about that focal-length range that attracts my eye--I love that it allows me to fill the frame with relatively distant subjects (like the animal trainer working with a beluga whale shown here and shot at the Mystic Aquarium in Mystic, Connecticut--one of my favorite photos, by the way) and that it focuses very quickly. For a lot of the subjects that I shoot (lots of travel and wildlife), it's tough to get as close as I'd like, but I just can't afford to buy a 400mm or 600mm lens. When I use the 70-300mm on my Nikon D90 body, it becomes a 105-450mm lens! That is a whopping amount of lens for that price. If you add a 1.4x tele converter (Kenko makes an affordable converter that fits it) Kenko 1.4X PRO 300 Teleconverter DGX Nikon AF Digital SLRs it has a max focal length of 630mm (but you lose a stop of speed). Just be sure that any converter that you buy fits the specific model of lens.
I shot this photo of the Blue Angels at an air show in Rhode Island using the 70-300mm and I could never have done it with my 80-20mm because it simply weighed too much to hold over my head for an hour or more.