Land Rover Follow

Are you in the market for a digital single lens reflex? If you are then, according to the market research department at Canon you are not on your own. Forty-three per cent of potential digital customers are thinking of an SLR. So what’s keeping the credit card in the wallet? Several things – price, weight and complexity. Well, price is no longer a valid reason for avoiding the SLR. Entry level SLRs are about the same price as the better quality compacts. And weight has come right down with both Canon and Olympus boasting about their feather-light models, the Canon 1000D and the Olympus E-420. Olympus say their potential customers want an SLR that works just like the compact they are accustomed to using. That means that it will have “live view” in which the LCD is the viewfinder, and an all-in-one, wide-angle to extreme telephoto lens. These putative buyers can’t be fussed with a bag full of lenses when they have found that one 10X zoom on their compact is quite good enough. There are good reasons for opting for a wide ranging zoom. First, it obviates the need to change lenses in dusty conditions. If you are on the Serengeti stalking a cheetah and the Land Rover is churning up the dust then changing a lens will let that dust into the camera. That is always bad, even with automatic dust removal. Second, a super zoom is cheaper than the combination of shorter lenses needed to cover the same range. However there are penalties, which we have harped on before in this space. Distortions at the zoom limits are usually extreme. Resolution is not as good as with primes or short range zooms. The lenses are slower – for instance, the Tamron 28-300 lens (RRP $900) we have been testing has an aperture of f3.5 at the wide end, which is acceptable, but not fast, to f6.3 at the long end. f6.3 is a smaller maximum aperture than some cameras need for their auto focus to work reliably. We tried the Tamron on a Nikon D300, which has a sensitive auto focus system. When the lens is extended to 300mm the camera has difficulty focussing. Most of the time we relied on manual focus. Fortunately the focus mechanism is smooth and well damped. Tamron’s approach is to go for maximum extension at the long end and for a modest short end – not wide-angle at all. The Nikkor 18-200mm, (RRP $1200) is wider than the Tamron and less ambitious at the long end. Its aperture range f3.5 to f5.6 and it auto focuses quickly, precisely and quietly. The Tamron also works well enough at the 200mm point, so perhaps that should be regarded as its normal limit. Both lenses have image stabilisation. If you wouldn’t know barrel and pincushion distortion if you saw it and you have no idea what vignetting is then you could love either of these lenses. And, in any case, these effects are absent at intermediate focal lengths. *