So you've got yourself an SLR or Digital SLR? Now you'll need to start buying extras! One of the most important extras you'll probably ever need is a good telephoto or zoom lens. There are a bewildering number of lenses available and you'll need to be careful you get one that's compatible, especially if shopping via ebay.
Take the Tamron 572D lens for example. Type it into dooyoo, and the first four matches you'll get will be for four different camera types. Luckily I know that this particular lens is for the Nikon, Pentax, Minolta or Canon and a bit of working out leads me to believe the one I'm interested in writing about is the 572DE - E being for Eos (Canon). In fact this particular lens will work with traditional Canon EOS models, or the digital EOS range. The long and the short is that you should be very careful when selecting a lens, and double check before pressing the PAY NOW button.
We'll start at the end, with the price - second hand price probably around £75 - £125 depending on how skillful your shopping is. I paid £76 from Ebay. If this is too much for you, you probably should forget SLR's and stick with a PAS (point and shoot), as this is really a budget priced, entry level lens.
So, to some specs. It's an AF (auto focus) or MF (manual focus) lens, with a focal range of 70 - 300mm, f/4-5.6. It uses LD (Low Dispersion) glass, which if you really want to be get technical, reduces chromatic aberration. In laymans terms it'll improve sharpness of the image, contrast and colour reproduction - ie a better picture overall. In normal operation, the minimum distance to subject to obtain correct focus is around 150cm. Flicking the switch to the macro mode will however, allow focus down to less than a metre at 180-300mm ranges. Although this isn't that close, the combination of zoom and macro means you really can get great macro shots of insects and butterflies, without them even noticing, and fill the frame at the same time. The Maximum Reproduction Ratio in macro at 300mm is 1:2. - example shoot a butterfly with a wingspan of 10cm, and on your print at 100% it would be 5cm.
It'll take up a bit of space in your camera bag, at almost 8 x 14cm (extending to 19cm), and weighs around 425g. That's reasonably lightweight as zooms of this size go, but you'll definately feel it on the end of your camera, compared to your standard lens. You should get a lens case and hood with it, but check when you are buying second hand. You might also think about a UV filter, and you'll need a 62mm, or if you want to use a smaller one, say a 58mm, consider a 62-58mm step down ring as a cheaper option.
In use. Assuming you are familiar with SLR's and lenses, the Tamron should present no particular difficulties to you. A quick turn and click, it should sit firmly on your camera body, remove the lens cap and you are ready to go. The AF/MF switch is located at the end nearest the camera body, and it's very close, but still easy enough to change quickly. The arrow to the right of this indicates the level of zoom, starting at 70, and by rotating the rubber gripped barrel of the lens, slides easily up to 300 with the lens extending smoothly. Further up the lens barrel is the macro switch, which can only be engaged in 180-300mm ranges, as indicated on the switch itself. If you are in macro mode, you must switch back to normal in order to zoom back out to 70-180 ranges. Next up the barrel is the focussing ring. You can only use adjust this when in manual focus mode. The ring has familiar DOF markers in both ft and metres for both normal and macro modes, giving a good idea of focus even when your eyes aren't able to judge for themselves. The end of the barrel has a 62mm screw filter thread for attaching filters and a lens hood.
AF is generally pretty fast in ideal situations, but can be quite sluggish in more tricky situations, especially low light. The motor is also pretty noisy - perhaps that's unfair, but it's certainly not silent in comparison to some of the latest (but far more expensive) lenses. This may miss you a few shots at times, and fluster a few butterflies at times, but for a budget lens, you do have to make some sacrifices. I always place overall image quality at the top of the list, and whilst this lens probably can't beat the top end models for this either, I'd give it a slightly ungenerous 8 out of 10 for impressiveness, and a more generous 9/10 for value for money. There is some distortion at the longest focal lengths, but nothing to write home about, and in general non-specialist photography, quite acceptable.
You might find yourself needing a tripod at times, when zooming, as shake can be exagerrated, especially at a slower shutter speed.
In conclusion, a good all-round telephoto lens, for SLR / Digital SLR users who have limited funds available.