Virtually all point and shoot digital cameras are equipped with zoom lenses, mostly with 3X zooms and then there are the crazy beasts with even longer zoom ranges like 10X, 20X or even more.
The 3X zooms are usually set up so you get a moderately wide angle view at the smallest focal length, balanced by a reasonably narrow view at the telephoto end.
The tele end, you’ll find, is ideal for shooting portraits but not much more.
The reason? Pushing the zoom out to its telephoto extremity allows the laws of optics to come into play, defining a sharp focus zone around the subject, while allowing details closer to and farther from the camera to fall into soft focus. On many cameras there is a Portrait mode which helps this isolation effect by altering the lens aperture and other settings, but that’s another story …
The result? The person in the portrait is depicted sharply amongst a sea of extraneous detail, now rendered as a blurry background.
The telephoto end of your zoom can also be used as a dramatic tool to seemingly compress the objects in a shot, pull it all together and make an impressive, compacted statement.
The fishing boat shot is an excellent example of what you can do when your camera has a zoom with a long reach; this shot was taken with the zoom extended to a 35 SLR equivalent of 200mm. Notice how all detail in the subject is compressed, making a powerful composition.
Notice how much detail of the passengers has been captured in the tele shot of a Manly ferry about to berth.
Tricks of the Trade
There’s one thing of which you need to be aware: zoom lenses on digital cameras, when used at their telephoto extreme, need a bit of TLC if you are to get great shots.
The further you zoom out the more you need to keep the camera steady; a tripod is best, or lean on a fence or even a friendly shoulder.
It also helps to keep the shutter speed as short as possible, to avoid camera shake; if your camera has a Shutter Priority function, select a fast speed, say around 1/500 second. If you’re running out of shutter speeds, don’t be afraid to dial up the ISO setting to 200 or 400 … with modern cameras you’ll still get sharp, noise free prints.
Aim the camera’s auto exposure sensor carefully, preferably at a key part of the subject that is mid tone; don’t point it at a large white or dark object in the picture. The same lesson applies to auto focus – choose an element in the picture that is mid way in distance.
There’s another trap with the limited 3X zooms of compact digicams as well as the budget priced ‘kit lenses’ sold with DSLRs: as you zoom in you find your lens aperture shrinks. An f2.8 lens at the wide angle end of the zoom soon becomes an f3.5 lens at the telephoto end. Bingo! Your exposure needs to be twice as long.
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