focal length
7
5.5
- noun
- /ˈfoʊkəl lɛŋkθ/
- Specialized
:
longitud focal
- Adding an extension between the camera body and a normal fixed focal length lens will provide greater magnification.
- focal length lens
- long focal length
- short focal length
And very often you'll see the camera change its focal length.
- And very often you'll see the camera change its focal length.
- If we did a dual mirror setup, we could cut our our focal length in half.
- So it's like a two times focal length piece on it.
- So that's a long answer to starting with just understanding focal length.
- But that kind of is how focal length affects the pictures and video you're taking typically.
Examples
-
Telephoto lenses have a fixed focal length as opposed to the variable focal length of zoom lenses.
Academic text (1994) -
The distance between the optical center of that lens and the image plane is called focal length, and it's usually expressed in millimeters.
-
So this is called the focal length and the distance from this point that goes through the focus.
-
The distance of this plane to the film is the focal length.
Academic text (1994) -
Are you changing the focal length of the lens?
-
The longer the focal length, the smaller the maximum aperture and the greater the physical size.
Academic text (1994) -
A "zoom lens" with a focal length of about 80-200mm is a good choice.
Academic text (1993) -
Some telephotos have focal lengths greater than even the longest zoom lens.
Academic text (1994) -
Parameters f, h, and alpha denote the camera's focal length, height from the ground plane, and tilt angle, respectively.
Academic text (1995) -
The photographer adjusted the focal length of the lens to capture a sharper image.
Synonyms
The distance from a lens or mirror to the point where parallel light rays meet
How Long
- Specialized
5
3.9
- Specialized
7
5.5
675
2.7
- Specialized
5
4.0
Surface Forms
Morphology
The compound combines 'focal' (relating to a focus or point of convergence) with 'length' (a distance or measurement), so its meaning — a distance associated with the focus of a lens — is directly derivable from the parts. Although the term is technical, the compositional logic is regular and cross-linguistically common, so a B1 learner who knows the constituent meanings can grasp the general sense.
Etymology
Focal length comes from the simple picture of a lens and its focal point: focal means the 'focus' where light meets and length means the 'distance' from the lens to that point. So the focal length is that distance, and that is why it tells you how much a lens will zoom in or how wide the view will be.