Lens Basics for Dog Photography
When you purchase a camera lens for your dog photography sessions, consider its focal length and speed (in addition to the crop). The focal length determines the field of view or amount of the scene you can see through the lens. The speed of a camera lens refers to how wide its aperture (the hole that lets light through) can open up.
Aperture is measured in increments called f-stops, and the wider your aperture gets, the more light it lets in, allowing you to have a faster shutter speed, which is important for dog photography. Also, the wider your aperture gets, the lower its f-number is. A fast lens is capable of very low f-numbers, like f/2.8 and below.
If you’re looking for the perfect lens to use for dog photography, buy the fastest lens you can afford if you plan on using shallow depth of field to really make your subject pop off the background. A fast lens also comes in handy on cloudy days when you need more light or during action shoots when you want to use a very fast shutter speed.
Also look for a zoom lens with various focal lengths so you can quickly adjust your field of view as your dog moves about without having to physically get closer or back up. A zoom lens gives you much more flexibility than prime lenses. The most versatile lens is a 24–70mm f/2.8.
Don’t be confused by the term fast when it’s used to describe a camera lens. It actually has nothing to do with the speed at which the camera focuses, saves the image, or anything like that. Camera lenses that are capable of opening up to very wide apertures (f/2.8 and below) are considered fast because you can get away with using very fast shutter speeds.
For instance, if you use an extremely fast shutter speed, like 1/5000 second, you also let very little light into the camera. To compensate for the lack of light coming through the shutter, you may need to use a larger aperture.