what is "IS" means in "....f/2.8 L 'IS' ..."?

Question

about lens what is IS mean....and,what are the differences between EF 70-200mm f/2.8 L IS USM and EF 70-200 f/4.0 L USM...
give me the detail...

Answer 1

Those are some great lenses.
The f/2.8 version gives you an extra aperture stop. F/2.8 provides very shallow depth of field (nice for portraits, etc.), and it also cuts the shutter speed in half compared to f/4 (making it better for low light situations).
Image stabilization (IS) mitigates camera shake. To be more precise, it lets you get away with slower shutter speeds (with hand held shots). With a 200mm lens, that comes in pretty handy - normally you'd need to use a shutter speed of 1/320th second on a digital Rebel or 30D. That might not be a problem on a sunny day, but sometimes it can be a real pain. With IS turned on you can use a shutter speed of just 1/80th. If you dip below those values, you'll need to have either a very steady hand or a tripod.
The image quality of all of these L lenses is excellent.

Answer 2

"IS" lens means that this lens has a image stabilizer. (helps to minimize blur photos. Also can be look as making your lens faster.)

EF 70-200mm f/2.8 L
EF (means that it will fit any camera with EF bracket)
70-200mm (mean that you will get 70-200mm focal lens)
f/2.8 (means a f-stop of 2.8, the lower the number the faster the lens)
L (this lens rating, L is the top rated)

So, EF 70-200mm f/2.8 L IS is much better and more expensive then the EF 70-200 f/4.0 L USM since its faster and will stabilize your images.


GL.

Answer 3

That all depends on what the definition of "IS" is.

(sorry for the humor- but the other two posters already answerd your question... I'll go back to the politics forum now :) )

Answer 4

Morey, isn't "is" the third person form for the verb "to be?" Talk about a politician...