Fast Lenses?

[Bufo Bill]

Came across the term "fast lenses" today. Literally no idea. What does it mean?

All the best from Bill.

 

[Ady N]

f/1.4 or f/1.8 or f/2.8
Allow for a wide aperture meaning more light gets in allowing for faster shutter speeds - hence the term 'fast'

 

[Bufo Bill]

Aaaahhhhh . . . Now it makes sense! Thanks!
All the best from Bill.

 

[ukaskew]

It depends on the focal length as well, a 500mm f4 would be a 'fast' lens, but anything below 300mm at f4 wouldn't be thought of as particularly fast, in my opinion.

Add prime vs zoom into the mix, a zoom would get a bit of slack when thinking in fast terms...a 24-70mm 2.8 is a fast lens, but a 50mm 2.8 wouldn't be regarded as particularly fast.