How to Buy a Lens for a Digital SLR Camera

Views 1 Like Comments Comment
Like if this guide is helpful
How to Buy a Lens for a Digital SLR Camera
Buying a lens for a digital SLR camera, particularly if the user has had very little experience in the area, can be a bit of a minefield. There are many different lenses available on the consumer market, and knowing which type to buy, which ones will be suitable for which camera ,and so on can be very daunting. Lenses are not a simple topic, and using a high quality, appropriate lens can make a big difference to the final product of an image. Follow the guide below to learn what to look out for in a potential DSLR lens purchase, what kind of lenses are available, and where to find them.

What are Lenses?

Firstly, any potential buyer needs to know what DSLR lenses actually are and what they do. Unlike most other types of cameras, part of the appeal of owning and using a DSLR is that lenses can be changed, which gives the photographer a much wider scope with which to take the images they require.

The Aspects of Lenses

There are two aspects of lenses that any potential buyer should be aware of - focal length and sensor size. Lenses are defined in millimetres, and the measure of that is the focal length. This measurement is the distance between the sensor and the optical centre of the lens. At a basic level, a short focal length enables the photographer to stand close to the subject of the image so that they fill the frame and items in the background seem further away than is normal. Short focal length lenses are commonly sizes such as 15mm, 20mm, or 35mm. A long focal length allows the photographer to stand a great distance away from the subject of image, which will still fill the frame, but items in the background will seem closer than is normal. Examples of long focal length lenses are 85mm, 105mm, and 300mm. In order to help the user identify what the focal length of the lens is, the range will be printed on the side, with the most commonly used focal lengths indicated on the lens barrel to help the user find the focal length they require. Regarding the sensor size, some of the more expensive DSLRs come equipped with a full-frame sensor which is equivalent in its size with that of a 35mm film negative. Entry-level DSLR cameras are equipped with less than high level full-frame sensors as they are cheaper and easier to manufacture. This needs to be taken into consideration when deciding on what lenses to buy. As an example, a standard-sized 50mm lens has roughly the same focal length at the naked eye, but if it is attached to a camera with a smaller sensor, this lowers to around 35mm. A 50mm lens on a high level DSLR camera with a full-frame sensor will be closer to 80mm.

Types of Lenses

Lenses are generally grouped into different types. These types are wide angle, standard, telephoto, macro, and prime. Wide angle lenses are normally 28mm or less and good for taking photos of interiors and landscapes. They allow the photographer to take a lot into a single image and are particularly popular for documentary photography where a lot needs to be included in both the foreground and background. This type of lens can create amazing photographs, particularly if used by an experienced photographer, but it is always worth remembering that if used at the widest setting, the edges of the image will become slightly stretched. This can have an impact if people or other focal points are stood at the edge of the photo. Standard lenses usually come with the purchase of a DSLR camera. They are good for portraiture photography as they give an accurate image that looks natural and free of any distortion. Standard lenses are a basic type that most resembles the lens used in point and shoot and bridge cameras.

Telephoto lenses are useful for sports or wildlife photography as they enable the photographer to take excellent images from a great distance. They can also be used for taking candid photos where the user does not want the subject of the image to be able to see them taking the photograph, such as in wedding photography. However, images taken using a telephoto lens can look slightly flat or 2-dimensional as they compress the background and foreground of the image so that it becomes difficult to tell how far the distance is between objects in the images. Macro images allow the photographer to take very close images of small things such as flowers and insects so that the subject can look as large or larger than life. Prime lenses are different to other types of lenses as the focal length cannot be changed. While zoom lenses (which applies to most other types of lens) can vary their focal length, which is useful as it does not require the user to change the lens, prime lenses are different. Most prime lenses are 50mm only although there are 35mm, 85mm and 300mm ones also available on the market. While they are not as convenient as zoom lenses, they have the benefit of being extremely detailed, providing the most high-quality shots of any lens on the market. They have large apertures, which means they are fast lenses and a lot less complicated to use than zoom lenses.

How to Find the Best Digital SLR lenses

Six things should be considered by any potential buyer when considering which DSLR lenses to buy. Firstly, the brand of the SLR should be considered. Most modern day lenses have some kind of connection to the camera that is being used so that the lens can relay information to the brain of the camera, which means that some lenses will only be compatible with some types of DSLR. Therefore, the manufacturer of the camera should be considered when potential purchases are being made or at least a third party manufacturer which is compatible. The lens mount of the camera is what is used to connect the lens to the camera, and with some models, adaptors can also be bought to allow different makes of lens to be used. The six things to consider are:

  1. Determine the focal length needed
  2. Decide on a prime or zoom lens
  3. Decide on the maximum aperture
  4. Decide on a first or third party lenses
  5. Evaluate any extra features
  6. Read reviews


There are many different lenses available on the market, and to a beginner buyer, it can be difficult to make a decision. Always conduct sufficient research before making a decision as digital SLR lenses come in a variety of shapes and sizes and there is a considerable difference in price between many of the different types.

There are several different types of lenses, all of which have their respective uses, and many photographers, particularly non-professional ones, will not need all of each type. It is best to build up a collection of lenses starting from those that will be best used.

Have something to share, create your own guide... Write a guide
Explore more guides