Beginner's guide to camera lenses

A camera lens serves three functions: it allows light to pass through the camera; it allows the lens to focus, and lastly, the lens dictates the format of the photo, whether it shows a narrow or wide view. The basic types of lenses on offer in this regard are: standard, zoom and wide angled lenses.

Basic Types of Lenses

Telephoto Lens Format

Telephoto lenses work rather like a telescope, bringing far objects closer to the viewer. Objects appear flatter, with less distortions. Far objects appear bigger than in reality, and proportions between large and small and near and far are diminished. Telephoto lenses, opposed to the zoom, are a fixed in focal length offering only one format. This type of lens can be found in a number of sizes from 200mm to 800mm (or more). Powerful telephoto lenses might be ideal for capturing wildlife from afar, or to eradicate distortions from a portrait.

Definition of a Zoom Lens in Photography

The zoom lens, as the name suggests can be zoomed in or out and therefore offer a range of focal lengths without actually changing the lens. Most digital cameras have a zoom lens of between 40mm and 100mm or so. This offers conveniences and versatility for shooting a range of everyday subject matter. But anything outside this ‘normal’ range will require the use of a digital SLR, as lenses of the everyday digital camera cannot be detached.

Camera Lenses for the SLR

The extreme photographer may wish to use an array of lenses, including those that fall outside the norm, as lenses can be detached from the digital SLR. Specialized lenses can be used, not possible on an ordinary digital camera. The only trouble with this is that carrying specialised lenses can be bulky.

Most digital cameras possess a zoom lens offering a range of focal lengths that are most commonly used. Other cameras possess a fixed viewpoint, which might be the ‘standard’ view. And then there are the digital SLRs who have a lens port that allows detachment and lens changing. The standard lens is 50mm, closely resembling our view in front of us. Millimeters, by the way describes the distance between the centre of the lens and the focal point achieved on the CCD behind it. Varying this factor means objects can be made to appear close-up, or far away without actually shifting our position. With this in mind, what are the main types of lenses?

The Standard Lens for Digital Cameras

The most commonly used format, the standard lens creates pictures that appear ‘normal’, or in other words how we see the world with the naked eye. Size of objects appear the same or similar in size as the object in real life. There are few distortions; proportions of objects against one another make sense. This, the 50mm lens will often be found on digital cameras including the fixed lens, (although some fixed-lensed cameras might be a little wider than this to accommodate landscape photography).

The Wide Angled Lens

If we push the ‘frame’ of a normal view outwards, so that more objects can be seen around us, the view would become wide-angled. This is what it is like to peek through a wide-angled lens. Tall objects appear bowed, differences in sizes and distances between near and far objects become more extreme. Wide angle lenses add depth and drama to landscapes, seascapes and other panorama. The widest lens, the fisheye lens is around 20mm. Some estate agents use the wide angled lens to make rooms look bigger than what they actually are in property schedules (I’m sorry but they do!).