CraigFair wrote:
That is total nonsense. Why would the Camera care if the lens was attached to a Tripod.
Is there a Magic Sensor in the lens that says "Beware Camera, don't focus, we are attached to a Tripod". :lol: :lol: :lol:
Actually it's
not nonsense.
What happens with
some lenses is that stabilization goes into sort of a feedback loop where when there is no movement, the stabilization actually creates it. This
will cause blurred images (camera shake blur... it doesn't normally effect focus) and is fairly obvious in the viewfinder when it's occurring. You'll see the scene jumping around rapidly. (Not to be confused with a slower "drift" which most IS lenses tend to do, which doesn't effect image sharpness at all.)
Associating it with a tripod is actually an over-simplification. It only occurs when there is absolutely no movement, [/i]such as[/i] might occur when fully locked down on a tripod. But, there are some techniques with a tripod when there's plenty of movement to keep the stabilization busy... And, it also can occur if resting the camera on really stable surface or even if doing a really, really good job hand-holding it.
With Canon lenses if the "feedback" effect does occur, there's no real harm done to either camera or lens. Worst that might happen is a shake-blurred image. As soon as you notice it happening in the viewfinder, simply turn off the stabilization. But, again, don't confuse it with some slight "image drift" that tends to occur, too.
The IS feedback effect doesn't happen with all Canon lenses... or even with "many" of them. In fact
most Canon IS lenses are "tripod detecting". They'll turn off IS in the absence of any movement. Only a few Canon lenses are known to
not do this: 24-105L IS, 28-135 IS, 75-300 IS (discontinued model), 300/4L IS, and the original 100-400L IS are among them.
In most of their lens' user manuals Canon does mention turning off IS when on a tripod. However in most cases this is only a suggestion to help save battery power, not related to any sort of "feedback" issue at all.
All this is per Chuck Westfall, Canon USA's tech guru... as well as many users including myself.
The battery power saved is pretty minimal. I've been shooting with IS lenses for 15 years and almost never turn it off on any of them. I get far more shots per charge than Canon estimates by using other power conservation methods (minimize use of the LCD screen, don't use the built-in flash, set the camera with a short sleep delay).
All this pertains to Canon IS on Canon lenses... I haven't used them enough to say if Tamron VC or Sigma OS or Nikon VR will act exactly the same. Likely they are all a little different, since there are probably patents involved that prevent the manufacturers from exactly copying Canon's IS or each other.
In fact, a lot of Nikon shooters feel that their VR slows down autofocus a little and there seems to be some test data to support that notion. With Canon I feel it's just the opposite, that IS helps their lenses' autofocus perform better. I don't have any objective test data supporting this... just a lot of experience with a variety of IS lenses.
10MPlayer wrote:
...do you think turning it off applies to use on an monopod. I can never keep a monopod as still as a tripod so I leave it on. ...
Leaving stabilization on while on a monopod is probably the correct call. Occasionally you might manage to hold everything so steady that the feedback occurs... But the odds are much, much better that there will be some movement for the stabilization correct. I never turn it off when on a tripod.
If you are unhappy, it's f22 that's your problem. Read up on "diffraction" to understand why (
http://www.cambridgeincolour.com/tutorials/diffraction-photography.htm). But, basically, if using a crop sensor camera I'd stay to f8 or f11... if using full frame, f11 or f16 at the smallest.