Originally Posted by ShtSh00ttr
I think Gen 3 on L lenses and Gen 4 can auto detect tripod mounting and disable IS .
Also, I can see some softness in IS vs NON-IS lenses at 100% crops. Nothing you will ever see unless your pixel peeping but IS lenses even with the gyro's off (manually or auto-detected off) do show some very minor softness compared to their NON-IS versions. This though is the same as far as lens to lens variants ..... same lenses much like CPU's do not have 100% same results.
All in all.... IS is a huge help in low light non-moving targets, worth the premium and hardly noticeable unless at 100% crop
I don't know whether all this is true or not, but even if it is, the tiny bit of extra softness is nothing compared to the lower ISO and/or faster shutter speed you can get with IS - at which point you now have to consider the environment you're shooting in.
Then again, certain lenses' weight is like an IS system of it's own. I know for a fact that I can hold a 24-70 a lot steadier than a 50/1.4.Edited by Manyak - 11/26/10 at 7:55pm