Select the right zoom lens mm f stop how to#

Let's zoom in on some scenarios to better understand which focal length will give the best shot. Rack focus is the recorded shift of focus from one object to another. This makes FFL the better option to use with gimbals.īoth types of lenses give you the opportunity to master a technique known as a rack focus. Unlike VFL lenses, weight does not shift as much in FFL. Same camera, switch to 50mm, the hyperfocal at f/8 is 34ft. For example, taking the 5D Mk II, focal length of 35mm, f/8, the hyperfocal distance is written as: 16.9ft. Fixed lenses often provide faster apertures such as f/1.2-f/1.8, which creates eye-catching critical focus on your subject, which is great for studio interviews. So look at the DOF Calculator here, enter your camera, focal length, choose an f-stop, and look on the right side for the hyperfocal distance. For example, the fastest aperture when shooting at 85mm on a 24-105mm lens is usually f/4-f/5.6. Fixed focal length lenses usually provide more clarity because of less glass and come with a faster aperture. A fixed focal length lens - often referred to as a prime lens - has only one focal length, which cannot be changed. If you choose fixed focal length lenses (FFL), you will need a number of lenses with fixed focal lengths if you will be recording images with varying depths of field. f/3.5-5.6G: Maximum aperture size when zooming at 18mm focal length and. The ability to zoom in and out with VFL lenses makes these lenses more versatile for uncontrolled action and allows you to pack less for the field. Lenses are essential pieces of gear, but choosing the right one can be. This effect is known as lens compression. As an example, a 100mm lens will make the subject twice as large and show less of the background than the image produced by a 50mm lens.

As I said in my comment above, the physical size of the opening will change when the focal length of the lens changes. But when you zoom in to 55mm, the f/stop becomes 5.6. From that same position, a lens with a longer focal length will make the subject larger, eliminate some of the background and exaggerate the depth of field. In your example you say at 18mm, the f/stop is 3.5. Aperture is expressed in an f-number, or f-stops. Aperture, or lens speed, refers to the maximum opening of a lens. For product photography, I typically use a telephoto lens of 85mm or higher with a good lens speed for depth of field. From a stationary position, if the lens has a short focal length, the object being documented will be smaller and more of the background will be shown. Anything smaller than 50mm could produce wide-angle distortion. Variable Focal LengthĪ variable focal length lens (VFL), more commonly called a zoom lens, can change focal lengths within a certain range, thereby changing the magnifying power of the lens by zooming in or out.

If you are carrying fixed focal length lenses, you will need to change your lens to capture wide, medium and close-up shots. When you carry a variable focal length lens, you will be able to produce a variety of shots. There are two types of lenses in photography and videography: variable focal length and fixed focal length.

Select the right zoom lens mm f stop how to#

Because the size of the subject in an image is directly proportional to the focal length of a lens, knowing how to select the right focal length for any given situation is crucial to successful shoots.