focal length
Convergence distance measure
Focal length is the distance from the center of a lens or curved mirror to the point where parallel light rays converge to a sharp focus.
In photography, focal length determines magnification and field of view: a short focal length captures wide scenes, while a long focal length magnifies distant subjects.
A 50mm focal length approximates human vision.
Adjustable optical inlet
- lensLight-focusing curved glass
- diopterUnit of focal power
- f-numberAperture-to-focal-length ratio
- refractionWave bending between media
convergence · divergence · magnification · collimation · ray tracing
Corrective lenses worn
- contact lensesVision aids worn on eyes
- myopiaBlurry distance vision
- hyperopiaDifficulty seeing nearby objects
- presbyopiaAge-related near vision loss
astigmatism · corrective lens · diopter · optometry · ophthalmology · accommodation · refractive error · bifocal
Instrument magnifying faraway objects
- microscopeInstrument for viewing minute objects
- binocularsHandheld dual-lens magnifier
- eyepieceLens you look through
- objective lensLight-gathering optical element
camera obscura · projector · magnifying glass · spotting scope · rangefinder · periscope · endoscope · collimator
Magnifying camera lens
- wide-angleEncompassing broad vistas
- zoom lensAdjustable-magnification camera optic
- prime lensNon-variable focal length optic
- f-stopLens opening ratio
depth of field · bokeh · full-frame · field of view · perspective distortion · compression · portrait lens · macro lens
aperture
Adjustable optical inlet
refraction · convergence · divergence · magnification · collimation · ray tracing
eyeglasses
Corrective lenses worn
- contact lensesVision aids worn on eyes
- myopiaBlurry distance vision
- hyperopiaDifficulty seeing nearby objects
presbyopia · astigmatism · corrective lens · diopter · optometry · ophthalmology · accommodation · refractive error · bifocal · progressive lens
telescope
Instrument magnifying faraway objects
- microscopeInstrument for viewing minute objects
- binocularsHandheld dual-lens magnifier
- eyepieceLens you look through
objective lens · camera obscura · projector · magnifying glass · spotting scope · rangefinder · periscope · endoscope · collimator · spectrometer
telephoto
Magnifying camera lens
- wide-angleEncompassing broad vistas
- zoom lensAdjustable-magnification camera optic
- prime lensNon-variable focal length optic
f-stop · depth of field · bokeh · full-frame · field of view · perspective distortion · compression · portrait lens · macro lens · angle of view
- astronomystars, moon, sun, planet, planets
- photographycamera, photo, flash, lens, shooting
- stargazingtelescope, stargazing guides, night sky, stars, constellation
- cinematographycamera, lens, shot, shots, lighting
- opticslens, lenses, mirror, mirrors, prism
- camera lenseslens, 50mm, macro lens, zoom lens, wide-angle lens
focal lengthaperture
Adjustable optical inlet
f-stop · depth of field · magnification · field of view · sensor size
length, focal, unfocused, refocus, refocused, refocusing, focalize, defocus, defocused