Interference of IS with flash/high shutter speed ?

[istvan_sandor]

Hi,

When using my 70-200/2.8 IS with IS on, I often experience blurred images when I

use flash OR shutter speed above 1/1000. (and no blurred images with IS off)

Could anyone tell me whether there is a "normal" technological reason behind

this or something is wrong with my camera/lens ?

[jimstrutz]

The most common reason for blurred images when flash is used is the shutter speed is so slow as to allow the ambient lit scene to show camera or subject movement. The simple cure is to raise the shutter enough that that the non-flash lit parts of the scene to become darker, and the flash lit parts are stopped by the flash.

 

Odd that faster than 1/1000 would show blur with IS though. Perhaps you have something else going on here.

[PuppyDigs]

You don't need IS at 1/1000 with a 70-200 lens. I normally turn IS off in bright light. I

engage IS when shutter speeds approach my handhold limit, e.g., 1/250 at 200 mm.

 

I use IS with flash all the time and it works great. It steadies your hand but does nothing for

subject movement.

 

However it is possible a quick "jab" at the shutter button could befuddle IS, especially if you

do it before IS has a chance to settle in.

[lester_wareham]

You may be firing before the IS has settled, that will cause blur settling takes at least 0.5 sec, longer if you want the full effect of the newer 3-4 stop IS lenses.

 

But as noted, you need the IS with flash so turn it off.

[digitmstr]

Can you post a sample?

[pkallos]

I might have noticed the same thing. I just took some photos last week out in a playground with my 70-200 with IS turned on and very fast shutter speeds ( no flash ) and most of them seem blurry. I was using AI Servo mode, so I was initially thinking that was the problem.