How do prime lens allow variance of focal length when focusing?
4389
How can a lens with a single focal length focus on more than one plane?
85837
What's the difference between real and effective aperture?
86838
What do the red values mean on the distance scale of a lens?
47999
How do you find out the "sweet spot" of a lens?
51290
Does my crop sensor camera actually turn my lenses into a longer focal length?
10570
Does sensor size affect lens distortion?
152115
Can I convert binocular zoom to equivalent lens focal length?
20086
Why is the amount of light a lens lets in called the 'lens speed'?
94271
What is the reference plane used when the minimum focus distance is measured?
54122
Why does using a tilt-shift lens make things look miniature?
63434
Technically, why is the out of focus area blurred more when using a bigger aperture?
12994
Is it physically possible to build a long zoom (17-300 mm for example) at an aperture value of around 1.4 or 1.2?
149797
What determines the sharpness of a shadow?
35335
What is the relationship between focal length and shutter speed?
7092
How do I focus in low light for long exposures?
47620
How does a circular lens produce rectangular shots?
129613
Why does illuminance stay the same for a given f-stop even when focal length changes?