The beauty of cameras supporting interchangeable lenses is that you have an array of options to choose from to suit your photography needs. But buying a lens for your camera is more than just what you want; there are some factors to consider as well.
Lens Factors to Consider
- lens options – Even if you’re not buying a lot of lenses at once, it helps to know just how varied your options are. A large collection offers a range of possibilities, from wide-range options to telephoto varieties and everything in between.
- photography style – Are you mostly a landscape photographer? Do you mainly shoot portraits? Or are you someone who dabbles in lots of styles. Knowing what you want to shoot helps you choose the types of lenses to purchase.
- hardware mount – Panasonic and Olympus both use the Micro Four Thirds mount. Canon DSLRs use EF or EF-S mounts while the EOS-M series makes use of an EF-M mount. DSLRs from Nikon use the F mount. While you can use an adapter to use lenses from different makers, it won’t function as designed.
- camera sensor format – The focal length of a lens varies depending on the size of the imaging sensor of the camera it is mounted on. The most common formats are full frame, APS-C, and Micro Four Thirds (MFT).
To know how a lens would translate in a different lens is to multiply the camera sensor’s crop factor by the focal length of the lens. An APS-C sensor has a 1.5x crop factor. So an 18-55mm lens has a 27.82.55mm full-frame equivalent.
An MFT lens is smaller than an APS-C and has a 2x crop factor. This means that a 14-42mm lens has a 28-84mm full-frame equivalent.
Why is it important to consider your camera’s sensor size? As illustrated, lens range will translate differently depending on the sensor size. For instance, a 25mm lens won’t provide wide-angle views on an MFT camera due to the 2x crop factor.
- lens type – You can take a pick between a zoom lens or a prime lens. A prime is basically a fixed lens, meaning it only has one focal length. There are advantages and disadvantages to both:
- zooms cover a wider range
- primes are better in taking bright and sharp photos but only offer one field of view
- primes are better in low-light situations
- primes have specialty options: macro and fisheye
- aperture – It’s not unusual to see lenses with the same focal length but sold at different prices. It’s the aperture that makes the difference; the larger the aperture, the more light it can let in and therefore more costly. For instance, Canon has 50mm f/1.8 and 50mm f/1.2 lenses, with the latter being more expensive.
Aperture is also presented in ranges, for instance 18-55mm f/3.5-5.6mm. This means the widest it can offer at 18mm is f/3.5 and f/5.6 at 55mm.
- image stabilization – This helps reduce shake and comes in handy in camera bodies that don’t offer in-body stabilization. Makers identify their stabilization tech differently: Canon uses IS, Nikon VR, and Sony OSS. Image stabilization might not be so much a priority but it sure helps if you want to shoot in low-light conditions.
There are far more advanced factors to consider but the ones presented above cover the basics. Take them into consideration when buying a lens.