Camera Lenses explained

Lenses are the eyes of a camera used to project an image of the subject onto the recording material (sensor in digital cameras and film in older cameras). Lenses are either built into the camera (fixed) or they can be removed (interchangeable). They'll also have a fixed focal length or will have the ability to zoom. A zoom lens will let you literally zoom in and out to have more or less of your subject/chosen background in the image.

A zoom lens will help you capture a variety of shots more easily as you  won't have to change your lens every time you want to alter the image. They're perfect for a press photographer who needs to frame quickly and correctly to capture fleeting moments. If you're photographing something like a car that's moving away from you a zoom lens would be more useful because if you tried doing this with a fixed focal length lens, you'd end up cropping some of the image out as you can't re-frame/adjust the focal length to match the new position of the car. However, lenses with fixed focal lengths are generally smaller, lighter and can be cheaper, but if you plan on buying several fixed focal length lenses, this can often become rather more expensive than purchasing a couple of zoom lenses. Fixed focal length lenses generally work better in low light conditions (photographing indoor sporting events or at a football match in winter) and are also more useful when you want to blur the background of an image and leave your subject in focus.

Here are a few examples of lenses and what they're used for:

Standard lens

A standard lens will let you create an image similar in perspective and scale to what the human eye sees. A standard lens doesn't change the size of an object or add distortion to the subject in an image. Standard lenses for 35mm film cameras were 50mm while standard lenses for digital cameras with a smaller APS sensor have a 35mm focal length. Medium format cameras have standard lenses that are between 75mm and 105mm.

Standard lens

Short telephoto lens

Short telephoto lenses also see an image in a way similar to what the human eye sees and they're great for portraits. If you're shooting close-ups of people's faces, the lens wont make them appear distorted and will produce a more flattering image. A short telephoto lens will also let you take photographs further back, keeping a comfortable distance between you and your subject.

Long/Telephoto lens

These lenses are good at magnifying distant objects. They make objects appear larger/closer to you than they really are. It means you can take an image of a bonfire, for example, that appears to be just infront of you when really it's far enough away to not get your fingers burnt. These longer lenses can be rather large and if you plan on using them without a tripod, you wont need that gym membership for much longer!

Mirror lenses fall under this category and can offer even longer focal lengths (bring the subject even closer). Widely used for astronomic purposes, mirror lenses are made up of mirrors rather than the glass usually found in lenses. Light bounces off the mirrors and is 'folded' which is why these lenses can produce a longer focal length but still remain small. However, these lenses do have a few problems and can produce poor quality images.

200mm lens. The same lighthouse as above appears to be closer than it really is.

Ultra/Wide Angle

Ultra/wide angle lenses are good for capturing a large scene. It can exaggerate depth in an image and they often cause you to move closer to your subjects which means you give emphasis to the front while still capturing the background. For example, if you're photographing something such as a field full of flowers, by getting as close to the flower nearest to you as possible will exaggerate the size but you'll also be able to see the rest of the field. Wide angle lenses are also good for architectural photography as the wider the view you have available for this sort of work, the less distortion there will be. You can also use this lens for portraits to add an interesting, unique angle to your work but be careful, as it can make parts look extremely large and distorted.

14mm lens. This lens will let you capture the lighthouse and all the detail directly infront of the camera too.

Fisheye

A fisheye lens makes everything you take look like it's in a Goldfish bowl. A fisheye lens creates an extremely wide angled image which appears convex/circular. It's a useful tool for getting in close to something and still retaining the detail of the surroundings. It's also great for creating unique looking images like the two here:

Macro lens

Macro lenses are all about close-up photography. You can get in close to photograph details of larger objects and you can also capture sharp, life-size images of small subjects such as flowers and insects. They're also useful for product photography and for capturing other small objects. Macro lenses have a limited depth of field (how much of the image is sharp and in focus) so it is important you frame and focus on the most important part of your image.

Which lens

While any lens can be used to record any subject, some are better at certain jobs than others. This table rates each type of lens out of three stars to indicate how useful they are for various photographic scenarios.

	50mm Standard lens	Short telephoto lens	Long/Telephoto lens	Ultra /Wide Angle	Macro lens
Portraits
Landscapes
Architecture
Product photography/ close-up work.
Wildlife
Sports/action

We hope you enjoyed and learned a few things with this article from the ePHOTOzine Academy Series. This is just one part of a 13 part series - to view others follow the links below:

• ePHOTOzine Photography Academy - Part 1: Camera types
• ePHOTOzine Photography Academy - Part 2: Camera lenses
• ePHOTOzine Photography Academy - Part 3: Image types
• ePHOTOzine Photography Academy - Part 4: Apertures explained
• ePHOTOzine Photography Academy - Part 5: Shutter Speeds explained
• ePHOTOzine Photography Academy - Part 6:Exposure modes
• ePHOTOzine Photography Academy - Part 7: Metering explained
  
• ePHOTOzine Photography Academy - Part 8: Autofocus explained
• ePHOTOzine Photography Academy - Part 9: Focus Lock
• ePHOTOzine Photography Academy - Part 10: Drive modes
• ePHOTOzine Photography Academy - Part 11: The ISO speed setting
• ePHOTOzine Photography Academy - Part 12: White Balance
• ePHOTOzine Photography Academy - Part 13: Flash modes