It’s not unusual for filmmakers to end up with a large collection of both prime and zoom lenses once they’ve been shooting for a bit. While a zoom lens might seem like the better, more versatile optical choice, in filmmaking fixed focal length primes often deliver better results.
In the below video, In Depth Cine explains five reasons why many filmmakers prefer a prime lens over a zoom.
#1 Considered Perspective
The lens focal length you choose to film a particular scene ends up serving as a perspective on the world. A long focal length will help isolate characters from the background, while shooting with a wider focal length will help make viewers feel like they are part of the character’s world. When shooting with prime lenses vs zoom lenses you are forcing yourself as a filmmaker to make a decision about perspective. Ultimately it makes for more thoughtful filmmaking.
#2 Optical Quality
Because of the way they are designed, prime lenses often have a higher quality look than a zoom lens. This is because the build of a prime lens is much simpler than that of a zoom lens. They use less glass, which means that less light is diffracted, which will make for sharper images overall.
Generally speaking, a prime lens will be faster than a zoom, meaning the aperture will be able to open wider and let in more light. Primes tend to be much faster than zooms because of their simplified build. Shooting with a wide aperture makes it easier to shoot in low lighting scenarios. You can also shoot with more bokeh and be more deliberate about what is in and out of focus in your frame.
Prime cinema lenses have a much smaller footprint than a zoom cinema lens—making them an ideal choice for being able to shoot handheld in tight spaces. They also tend to be lightweight which makes balancing the camera while using a gimbal or a Steadicam a much easier process.
A zoom lens has some focusing limitations when compared to a prime lens—especially when it comes to close focusing capabilities. The closest an Angenieux 24-290mm zoom lens can focus at 50mm is four feet, while a Zeiss 50mm lens can focus up to 20 inches away. This means that you can be much tighter with your shots when working with a prime lens.