I got a Zoom Lens for Xmas: What Do I Need to Know?

I am a very amateur phtographer (emaphasis on very). I bought a Canon Rebel XTi a few months ago and have only used the kit lens for now. But my wife got me a 75mm-300mm zoom lens (no image stabilization) and I want to learn about the do’s and don’ts of using a zoom lens.

So teach away!

Clockwise makes things get bigger, anti-clockwise makes things get smaller.

Don’t zoom in if you can get closer.

Photograph mosquitoes and things like that.

Exactly. And this especially applies to videos/motion pictures. Nothing looks more amateur and hokey than someone zooming in and out ever other second.

You’ll generally need a macro lens for that; a 300mm won’t cut it for tiny stuff. I’m pining over a really nice Canon macro right now, but can’t convince myself to spend the money yet.

What are the exact specifications of the lens? There are several different 70-300mm Canon lenses, of varying quality levels.

The general rule of thumb is, if the shutter speed is slower than 1/focal length, you’re in tripod territory. For example, if you’re using an effective focal length of 200 mm, you shouldn’t be shooting slower than 1/200th of a second. In this case, with the 1.6 multiplier of the XTi this lens is effectively 450mm fully zoomed out. For this camera, that’s almost 1/500th second. You can do a little better with IS, but after that you go to a tripod.

A setting of about about 100mm is good for portraiture. Any wider and you start to distort the face, exaggerate the nose, lose the ears behind the head, etc. A normal lens stinks for portraiture.

I couldn’t disagree more. Normal lenses (about 55mm for 35mm film, 80mm for 2 1/4 film) are perfectly fine for portraiture. Please see the portraiture work of Helmut Newton, Diane Arbus, Cecil Beaton, Henri-Cartier Bresson, etc. Once you get wider than that, things start getting distorted unless you’re doing environmental portraiture. My favorite focal length for portraiture is 85mm (on 35mm format). With the 1.6 multiplier of the Canon sensor, everything in the 75-300mm is perfectly suitable for portraiture.