Although some cameras naturally work better in low-light conditions than others, if you have a digital SLR, you can improve your low-light photography dramatically by simply using the right lens. On Halloween night, for instance, you'll probably want to use a wide-angle lens with a aperture of f3.0 or less.

Sigma and Tamron have produced some of the most effective wide-angle lenses for low-light photography. The Tamron SP AF 17-50mm The Tamron SP AF 17-50mm is one such lens, with a maximum aperture of f2.8. At 5.3 x 4.1 x 4.1 inches and 1.2 pounds, the lens is relatively compact and easy to carry around. The fast f/2.8 aperture makes the lens nearly ideal for low-light situations. For a retail price of $450, the Tamron 17-50mm wide-angle lens produces some of the sharpest photos for the money.

Tamron SP AF 17-50mm Lens Features

Canon-compatible lens designed specifically for digital SLRs

17-50mm focal range equivalent to 26-78mm in 35mm format

Maximum aperture of f2.8

Filter diameter of 67mm

Minimum focus distance of 0.27 meters over entire zoom range

An equivalent lens by Sigma is the 18-50mm f/2.8 EX DC lens. Like the Tamron, this lens is compact enough for easy transport at 2.9 inches long at weighing just under a pound. In many ways, this lens is nearly identical to the one produced by Tamron, but it sells for less; only $375 retail.

Sigma EX DC 18-50mm Lens Features

EX lens series denotes excellence of engineering and new technology.

Compact and lightweight zoom despite large F2.8 aperture.

Excellent correction for various types of aberration provided by one SLD (Special Low Dispersion) glass element and two aspherical lenses.

Super Multi Layer (SML) coating reduces flare and ghosting

Focal Length - 18-50mm

For more on low-light photography:

http://www.slrtoday.com/articles/70/1/Low-Light-Photography-Tips/Challanges-of-Low-Light-Photography.html