As title really I was r a new canon lens looking at canon 200mm 2.8 L but is IS really needed
If you want to shoot hand-held below about 1/200sec, then yes.
I think that would depend on the lens and the person using it...
Its a 200mm and the op will be using it![]()
It just that I can get a Canon 200mm 2.8 L uses £350
Better to have and not need than to need and not have...
Missed that!
OP if you want the lens then get it. Most of my lenses don't have IS (including some very expensive ones like the 24-70 2.8 is ii ????, and 16-25 2.8 ii). With f2.8 you will be able to open it up plenty wide enough to get a decent shutter speed. Oh - and it doesn't help if the subject is moving anyway, it's only any good for your own shaky hands. I don't think it's the most necessary thing in the world.
then you didn't ask the right question.. a blanket is IS really needed... thats silly... you wanted to ask is it worth the extra cost between a non IS...... I would then change my answer to
Better to have and not need than to need and not have...

How many stops does IS hekps
Missed that!
OP if you want the lens then get it. Most of my lenses don't have IS (including some very expensive ones like the 24-70 2.8 is ii, and 16-25 2.8 ii). With f2.8 you will be able to open it up plenty wide enough to get a decent shutter speed. Oh - and it doesn't help if the subject is moving anyway, it's only any good for your own shaky hands. I don't think it's the most necessary thing in the world.
P.S. I've never believed in the rubbish about 1/lens length. I've got the 50 1.4 and I've managed my some miracle to get it to work at 1/25 before... People come up with rules and then state them as if they are facts. Everyone is different, so just get the lens.
And the number of stops is dependent on the lens and how much you believe the marketing rubbish. If you haven't got it then you don't need to worry about it.
The principle is certainly not rubbish, and though we're all different and circumstances play a big part, in practise it's a good rule of thumb. Camera shake is directly related to magnification of the 'optical system' which is effectively focal length x crop factor. So if you can successfully hand-hold a 50mm lens at 1/25sec, then you'll get the same standard of sharpness at 1/100sec with a 200mm lens, and so on. From this, it follows that image stabilisation is increasingly beneficial at longer focal lengths.
Edit: when you're on the limit, there's safety in numbers. If you shoot three or four frames together, they will all be different but there's a good chance that one will be acceptably sharp. And a monopod is a very good substitute for image stabilisation.