What is a parfocal lens?
A parfocal lens maintains focus as you zoom in or out. Once you focus on a subject, the...
Lenses & Optics
What is a macro lens?
A macro lens is designed to focus at extremely close distances, allowing you to photogr...
What is focus breathing?
Focus breathing is an optical phenomenon where the field of view changes as you adjust ...
What is a T-stop vs f-stop?
An f-stop is a theoretical calculation based on the lens focal length and aperture diam...
What is the difference between EF and RF mount?
Canon EF mount was designed for DSLR cameras in 1987 with a 44mm flange distance. Canon...
What does f/1.8 vs f/4 actually mean?
The f-number is a ratio of the lens focal length to the diameter of the aperture openin...
What is bokeh?
Bokeh (from the Japanese word meaning blur or haze) describes the aesthetic quality of ...
What is lens distortion?
Lens distortion causes straight lines to appear curved in your images. Wide-angle lense...
What is telephoto compression?
Telephoto compression is a visual effect where distant objects appear larger and closer...
What is focus shift?
Focus shift is an optical phenomenon where the plane of sharpest focus moves as you sto...
