Zoom lenses
Zoom lenses are a fabulous tool and I use 80-200 mm and the 80-400 mm VR on 135 format and the 100-200 mm zoom on 6 x 7 format. These lenses are top of the range and the optical results are excellent with little visual difference between these and prime lenses of similar focal lengths.The primary advantage of zoom lenses is that an operator can change focal lengths with a twist of the wrist. You can even flick from 35 mm to 300 mm, which covers a wide range of prime lenses!
I find this tool perfect for working "journalistically", looking for a visual story while I'm walking in parks, down busy streets, at the beach, driving the back streets of country towns. I may be walking a street and suddenly see a child playing close by. If I were to take my eye off the subject and change lenses, I might miss the shot altogether.
What about quality comparisons with fixed focal-length lenses? Zoom lenses today are, in some cases, better than the fixed focal-length lenses of years gone by. But today's best fixed lenses are still better than the best variable aperture zoom lenses. The optical tests we have seen show that fixed aperture Nikon 80-200, 28-70, and 17-35 mm AF-S are of excellent quality in resolution, flare and colour consistency and, for ninety-nine out of a hundred people, indistinguishable from the comparable zooms. This would also be the case with other top brands. A zoom lens does tend to have slightly less uniformity - brightness at centre versus brightness at the edge - and slightly lower, but only fractionally, edge resolution itself. The other point is that rectilinear accuracy (straight subject lines are straight in the image and there is no obvious distortion) is almost always better in a top quality fixed lens. Some zooms are called macro zooms but only focus to 1:6, so make sure of the specifications before you purchase.
Zoom lenses - This picture was taken at around 200 mm, zooming in tight to get a close shot of the feeding deer. This car moved on and within a few seconds a smaller vehicle had taken its place. I kept still and in a crouch because the deer were a little shy. By zooming back to around 120 mm, I was able to frame the next shot with the entire car and more deer included. With the sun coming over my shoulder, I captured the final shot when I noticed a young fawn trotting down the hill behind me, nicely back-lit. I zoomed back to 200 mm and the multi-pattern metering looked after the exposure.
Telephoto zoom lenses are fast and easy to use and they eliminate the need to change lenses for different focal lengths and to carry additional equipment. In this focal range you will find lenses of excellent quality, some of the newer releases offering outstanding zoom ranges. The Nikon 80-400 mm, with its built-in vibration reduction system, effectively takes the lenses from a speed of f5.6 up to f1.2! Canon offer a similar lens, and I am sure that by the time this book goes to press there will be other brands of even faster and possibly longer zooms. In terms of quality, I have found the results I get from my 80-200 mm f2.8 lenses indistinguishable from similar fixed focal-length lenses. The lenses are expensive, but that should be your guide; cheap lenses produce poor resolution and thus poor images.
The shots were sequenced within moments of each other, Taken with an 80-200 mm zoom lens.
One size fits all! - This Tamron 28-200 mm lens might be worth considering if you are a first camera buyer, if you want quality on a limited budget, or if you are travelling light, perhaps planning to wander Australia with a backpack. The focal lengths will cover most of your needs, and the lens is light in weight and small in size.