You may have heard the term prime and zoom used to describe a lens. All lenses fall into one of these two categories.
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You may have heard the term prime and zoom used to describe a lens. All lenses fall into one of these two categories. A prime lens has a fixed focal length, while a zoom lens has a variable focal length.
The benefits and drawbacks of prime and zoom lenses are a topic of some debate, but let us dive into the basic points of discussion.
A prime lens is defined by having a fixed focal length. What that focal length is can very greatly. Coming in super wide focal lengths all the way up to telephoto. The main factors to consider with a prime lens are maximum aperture, image quality, versatility, and cost.
The major areas where primes perform best are maximum aperture, and image quality.
They tend to have a larger maximum aperture. That larger maximum aperture will make it easier to get a shallow depth of field and will perform well in low light conditions, offering less grain to get proper exposure.
because prime lenses only have a single focal length, there are typically fewer elements, and no compromises need to be made to accommodate other focal lengths. This generally results in better sharpness and less distortion.
A zoom lens is defined by having a variable focal length. They have complex mechanics and can be physically longer.
Its simple to find out the focal length, as they are printed on the lens. This lens is labeled 24mm-105mm, which means it has a 24mm focal length when fully zoomed out, a 105mm focal length when fully zoomed in, and can achieve any focal length in between the two.
There are two different types of zoom lenses: parfocal and varifocal. A parfocal zoom holds focus as you change the focal length where as a varifocal zooms shift focus as you zoom. Varifocal zooms are more typical in photography based lenses and cinema zoom lenses are parfocal as defined by not changing focus over the throw or zoom of the lens.
The vast majority of present-day auto focus zoom lenses are varifocal. This means that the old-school video shooting technique of zooming to the maximum focal length, focusing, then zooming back out to a wider setting is not recommended. Instead, you should, if your camera has the option, digitally zoom in to your focus point, focus and then digitally zoom back out to the non digitally zoomed framing.
So what will you choose? Prime or zoom?
Lets weigh their pros and cons.
Primes typically offer a larger maximum aperture
However zoom lenses offer more focal lengths because of their versatility. To be able to shoot at custom focal lengths without purchasing additional lenses, or not having to switch lenses can be a great benefit, especially if you’re shooting in unpredictable situations.
prime lenses tend to be less expensive, but, you’ll need to buy multiple lenses to get the focal length flexibility of a single zoom lens.
No matter what you choose, there are strengths and weakness to each choice.