depth of field

(redirected from f-stop)
Also found in: Dictionary, Thesaurus, Financial, Encyclopedia, Wikipedia.

depth of field

For a given setting of an optical system (or a steady state of accommodation of the eye) it is the distance over which an object may be moved without causing a sharpness reduction beyond a certain tolerable amount. Depth of field increases when the diaphragm (or pupil) diameter diminishes as, for example, in old eyes (Fig. D1). Examples: viewing at infinity, the depth of field ranges between infinity and about 3.6 m for a pupil of 4 mm in diameter; and between infinity and about 2.3 m for a 2 mm pupil. At a viewing distance of 1 m, the depth of field ranges from about 1.4 m to 80 cm with a 4 mm pupil; and from about 1.8 m to 70 cm with a 2 mm pupil. See hyperfocal distance.
Fig. D1 Schematic representation of the depth of field and the depth of focus of an eye fixating an object at O (I, retinal image size corresponding to the tolerable resolution)enlarge picture
Fig. D1 Schematic representation of the depth of field and the depth of focus of an eye fixating an object at O (I, retinal image size corresponding to the tolerable resolution)
References in periodicals archive ?
For a different type of shot of boat fishermen, preset your camera to the correct shutter speed, f-stop, and distance, and hold it out over the water to shoot back toward the boat as a fellow angler casts or lands a fish.
When shopping for any lens, take note of its f-stop. The f-stop is a measurement of the diameter of the aperture, expressed as a fraction (f/1.4, f/3.5, and so on).
The InFocus M810's primary camera houses a 13-megapixel Sony Exmor R CMOS sensor with f-stop number of f/2.2, coupled with dual-LED flash.
"But it's not trying to look like them." Instead, Fujifilm elected to return to analog controls (an F-stop lens ring, a roller wheel for the shutter speed) since these are what serious photographers prefer.
While shutter speeds are simple fractions of a second, the f-stop is the focal length of the lens divided by the diameter of its opening (f/stop = A/FL).
The biggest advantage on set is that the light does not have to be adapted when switching lenses because they all have the same F-Stop. The lens speed is ideal for playing with the depth-of-field.
Then the display goes north of the Tyne to f-Stop Gallery in Byker, Newcastle, where it can be viewed from June 23 to August 5.
Photographers know that by reducing the diameter of the aperture in the lens (increasing the f-stop) they can increase the amount of the image that is in focus.
I had to put myself on a strict photo training regimen--taking notes, shooting tons of test rolls and buckling down to figure out exactly what the "F" of an F-stop was.
He had a concussion from a brick thrown at him during the melee between Chinese protesters and soldiers, and he'd borrowed the film in his camera, and his f-stop setting was wrong for the film he was using, and he was exhausted and horrified by two days of murder and mayhem in the world's largest public square, where students protesting China's junta were being mangled and trampled by the army.