Criteria s for Choosing a Camera Lens
Camera lens options are many and picking one can be more difficult than anticipated. However, knowing the right things to look for when making a lens choice can reduce the lens options from thousands to mere tens. Here are some important criterias to consider when making a lens choice.
The first thing to know about lenses is that lenses can only be attached to cameras through an interface called lens mounts(1). Also, note that lens mounts are found on both cameras and the lens itself.
Cameras can be primarily differentiated by brand, design, and sensor sizes. Most brands create their digital cameras in either DSLR or mirrorless designs, which is irrespective of the sensor size in the cameras.
These camera classifications are important to lens choice because every camera type, class, and brand uses a unique lens mount. For example, a mirrorless, MFT(micro four-thirds) sensor Panasonic camera’s mount is different from a full-frame DSLR Sony camera’s mount. Basically, the difference in the two camera types implies that the same lens can’t work for both cameras, and this translates to all the different camera brands available.
The good news is that every camera brand produce suitable lenses for their different cameras. In addition, some third-party producers also make lenses for different camera brands. To make choosing a compatible lens for your camera easier, lenses carry nomenclatures that signify the model(s) of camera they are compatible with. Another option is to use an adapter (helps with connecting different lens mounts). Adapters are only advised as a last option because they also have limits, and are not guaranteed to work.
The most important part of knowing how to choose the right lens for your camera is choosing the right lens mount because every other feature of the lens is hinged on the lens being compatible with a camera.
Another important criteria to choosing the right lens is the focal length of a lens. The focal length of a lens determines the type and class of the lens. These differences also influence the best use cases of individual lenses.
There are two types of lenses. Lenses with fixed focal lengths (Prime lenses) and those with variable focal lengths (zoom lenses). All things being equal, prime lenses produce better images than zoom lenses because their efficiency is concentrated to a single focal length. On the flip side, zoom lenses can work at different focal lengths which is quite useful for covering different distances without actually moving the camera.
Zoom lenses and prime lenses are further classified based on the focal length they can effectively work in. Here are the classes of lenses based on operating focal length.
These lenses provide users with the largest viewing angle available. Their base of operation is at the lower end of the focal length spectrum. Wide-angle lenses can be from 8mm to 35mm with the widest FOV being the 8mm. In fact, at the 8mm focal length, the lens will be experiencing extreme distortion, resulting in what is known as fish-eye lenses.
- Standard lenses
These are lenses ranging from 35mm to 50mm. They are the lens favored for filming majorly because the FOV is close to that of the human eye. Standard lenses, as their name implies, are good for general videography.
These are lenses with focal lengths above 80mm. They are specialized at viewing distant objects. Telephoto lenses can reach focal lengths over 600mm. Basically, the higher the focal length, the more distance the lens can cover, and the smaller the field of view (FOV).
Also read: Best focal length for video
The lens aperture(2) is another primary lens feature that determines the amount of light the camera’s sensor is exposed to. The aperture works in collaboration with the shutter. The impact of the aperture on lens choice lies primarily in the aperture range and the maximum aperture.
Lens apertures are represented with “f” followed by a number. E.g. f22 or f/22. With aperture, higher numbers mean smaller diaphragm openings while smaller numbers mean larger diaphragm openings. An f/1.2 aperture is larger than an f/22 aperture.
The aperture range comes in handy when a user is trying to change an image’s field depth. The depth of field of an image, in simple terms, refers to the area of the image, in focus. Wide aperture ranges give more room for control over the depth of field. Generally, smaller f-numbers result in smaller depth of field while larger f-numbers result in a bigger depth of field.
The lens mount is the foundation for every lens feature, without which the lens can not function.
Now, about a lens’s maximum aperture, lenses with wider maximum aperture are usually better because they can work with little lighting. Furthermore, good max aperture provides better subject isolation in an image frame. For example, a lens with a maximum aperture of f/1.2 will offer better subject isolation and be able to work with little lighting.
Other Criterias for Choosing a Camera Lens
While the features mentioned above are primary to lens choice, there are still more guidelines that can be followed to know how to choose the right lens for your camera. Some of these features are
A lens can either have automatic focus, manual focus or both. Irrespective of the type of focus a lens uses, the driving mechanism should be quiet and fast. A proper lens should also be able to focus accurately almost every time.
Individuals can also check for focus features such as minimum focusing distance and the resulting magnification index. The focus characteristics paint a picture of how close the camera handler can get to the subject before losing focus. While some lens focus features can’t be appreciated until it is acquired, individuals can check reviews for the lens focusing abilities.
- Optical Elements
Lens elements are the individual glasses in lenses that help achieve exceptional images. Among these lens elements are elements designed to help with optical aberrations. Some of the common special lens elements are low-dispersion elements, aspherical elements, and integrated coatings on the Lens elements to reduce the effect of excess lighting.
- Image Stabilization
This feature comes in handy when shooting handheld, and especially in low-light situations where the shutter speed is low. While some cameras have the IS feature, having a lens with this feature is an added advantage.
Also read: What is a Camera Lens?
Mild wide-angle prime lenses are preferred for filming because prime lenses produce quality images while the mild wide-angle produces the perfect field of view for the audience.
No. Only adapters can help connect different lens mounts and even so, they do not always offer full compatibility.
Learning how to choose a camera lens is easy as long as the right steps are followed. Sometimes, the options can be overwhelming (especially with the popular brands), however, strict adherence to your lens needs will reduce the lens options immensely.
What type of lens do you like to use? What’s your most important criteria for a lens choice? Feel free to tell us in the comments.
- Bjorn P. (2019 Aug). Introduction to Lens Mounts and Lens Adapters. Retrieved from https://www.bhphotovideo.com/explora/photography/tips-and-solutions/introduction-lens-mounts-and-lens-adapters
- Nasim M. (2022 April). Understanding Aperture in Photography. Retrieved from https://photographylife.com/what-is-aperture-in-photography/amp