How to select a lens for a DSLR camera

There are many, many lens choices and finding the right one for the subject can greatly improve the results.

Difficulty: Easy

Instructions

Things You'll Need:

• A DSLR (digital single lens reflex) camera which allows the use of interchangeable lenses.

1. A DSLR camera offers the option to select lenses which will perform better than the original equipment lens which comes with the camera.
   The other reason to purchase a DSLR camera is that it is capable of taking photos faster than small point and shoot cameras.
   DSLR cameras are the equipment of choice for capturing fast-moving subjects and using longer focal lengths to bring the subject closer.

2. To select a lens, first decide what you need to photograph.
   Indoor sporting and action events require what are called 'fast' lenses.
   These are lenses which have larger apertures (f/stops), and allow more light into the camera when open as wide as possible. This allows the use of faster shutter speeds to stop and capture action.

3. Longer focal length lenses bring the subject closer. The downside is that they are heavier, and thus, camera shake becomes a factor in shooting. Many lenses offer the option of 'anti-shake' or 'image stabilization' which tries to help sharpen the image and reduce the effect of camera shake. Some DSLR bodies have anti-shake built into the camera body and use standard lenses, reducing the cost of the lense. This would be a deciding factor when purchasing bodies or lenses.

4. A rule of thumb which comes from the 'old' days, is the the minimum useable shutter speed with a long lens is 1/focal length. In other words, if you have a 300mm lens, the minimum shutter speed you can use to counteract camera shake would be 1/300. This of course applies only to hand-held cameras without any anti-shake features activated.

Tips & Warnings

• For sports shooting, the common theory is that you need a MINIMUM of a 300mm lens to reach from the 35 yard line of a football/socccer field to the end zone to fill the frame with a full-length figure. Lenses of shorter focal lengths are useful in indoor events like gymnasiums where the distance is not so great.
• You can often find a non-brand name lense which not only offers a larger f/stop (a faster lens), but also will match sharpness of the manufacturer's lens at a lower price.
• Often it is possible to purchase a well-cared for used lens or a reconditioned lens from a reliable source (see links to bhphotovideo, or K+H used equipment) and have a totally satisfactory lens for occasional use.
• When using long focal length lenses, you must often use an additonal support to add to stability lost through the weight of the lens. It is often not possible to hand-hold large lenses. A monopod will add to stability and increase the potential for sharper images.
• So-called "fast" lenses have larger diameters, bigger f/stops, and aid in using faster shutter speeds.
• Long focal length lenses, with large f/stops will be noticeably more expensive than the smaller aperture lenses.
• If the lens has built-in stabilization features, the cost will also increase.

Resources

• lenses monopods used lenses reconditioned lenses