A system that automatically focuses on the subject in either the selected autofocus area in the viewfinder, or on the subject that is in the center of the viewfinder. Pressing the shutter-release button halfway down activates autofocus.
A method of focusing where focusing distances are set automatically. In 35mm SLRs, a passive phase detection system that compares contrast and edge of subjects within the confines of the autofocus brackets in the viewfinder and automatically sets focusing distance on the lens. Autofocusing motors may be in the camera body or the lens itself. Active IR (infrared) autofocusing systems may also be in 35mm SLRs in the form of beams in dedicated autofocus flash units, or, in a few models, built into the camera itself. Commonly found in amateur lens/shutter cameras. These beams are emitted from the camera or flash, bounce off the subject, then return and set focusing range.
Automatic adjustment of the acuity of cameras, projectors , and magnification devices.
System by which the camera lens automatically focuses the image of a selected part of the picture subject.
A system for automatically focusing a camcorder's lens so that the picture appears sharp.
A lens system that automatically focuses before the exposure is made.
The camera automatically focuses on the object to capture at which it is pointed; this object then becomes the sharpest part of the overall image.
Automatic, motorized focusing.
an optical device for focussing a camer or other instrument automatically
The ability to bring an image automatically into focus.
is a system that measures the phase of light arriving at a sensor to establish correct focus. This is good for those who don't know how to focus, but be careful that the camera focuses on the correct object.
The camera automatically focuses on a subject or object at which it is pointed which then becomes the sharpest part of the image.
Function of the camera lens automatically focuses on the subject in the chosen picture frame.
The facility of some lenses to focus on the subject without manual adjustment.
The camera lens focuses automatically, usually when the shutter release is half-pressed.
Automatic focus adjustment. There are basically two main AF methods: the focus detecting method, (or passive autofocus) usually employs a CCD and works by evaluating the amount of contrast or the phase difference in a scene. Distance metering (or active autofocus) utilises an (infrared) light emitter and receiver in a triangular surveying system. Alternatively, the camera may use ultrasound (sonar) and measure the time taken for the sound signal to return. This data is converted by a microprocessor into information about distance and thereby enables the automatic focusing of the lens.
a system built into camcorders which automatically focuses an image.
device used in certain cameras, projectors and enlargers that focuses the image automatically.
A technological innovation for vertical camera shots employing an up-and-down motion of the camera.
Automatic sharpening. In order to take a sharp picture the focal length must be accurately adjusted. Autofocus cameras achieve this automatically.
Camera feature that uses an infrared (IR) beam or sonar to set its focus.
When applied to a lens, it is the ability of a lens to focus automatically on an object within its focusing sensors. This system, considered superior to others, is able to achieve very precise focus in the majority of situations, but is dependent on the light sensitivity of the sensor. Active autofocus systems have, by their very nature, limited range.
The ability of an imaging system to control the focus of the lens to obtain the sharpest image on the detector. Edge crispness is a typical control variable.
The camera's ability to automatically focus on the subject to be photographed.
Camera mode in which the camera focuses upon the subject . Pressing the shutter release halfway focusses on the subject. Pressing the shutter release all the way takes the picture.
For the film of the same name see Auto Focus.