IS Effects On Image Quality

[frankie_frank1]

Does IS degrade image quality when there is no hand vibration at all?

[sattler123]

None that I have noticed. Is is a life saver!

[hakon_soreide]

If you have the camera on a tripod and there indeed is no vibration at all on long shutter speeds, then the answer is yes.

When you handhold, no matter how steady you are, there is hand vibration and/or mirror vibration.

[leopoldstotch]

It doesn't degrade image quality, but when on a tripod, older IS versions may introduce motion if none is found. Thats why its recommended to turn IS off on non-tripod sensing versions of IS. Same goes for your parallel post about VR.

[mars c]

There is no such thing as " no hand vibration at all", That thing dont exist.

 

My experience with IS were always positive , If you're looking for a lens, Choose the one with IS as much as possible.

[brucecyr]

Ah, guys, we gotta stop meeting like this!

 

It depends on what generation of IS you're talking about. In general, Canon's 2nd (and 3rd) generation IS figures out when its attached to something and doesn't try to correct non-existent movement. At least the two IS lenses I've had the most experience with, the 70-300 and the 17-55, hardly ever show any camera blur under any circumstance. Earlier IS, like that in the big teles, supposedly needs to have IS turned off when the lens is attached to a tripod.

 

As for no hand vibration at all -- first, the vibration doesn't really come so much the hand as from your body. Recent medical research using hundreds of micro-sensors shows that the human trunk is constantly falling one way or the other. What keeps you erect is a chorus of constant corrections by hundreds of little muscles around your midsection and in your legs that continually pull you one way or the other to correct falling. So in fact, the age-old notion of standing rock steady is a common sense myth -- and that is what IS counteracts.

 

Of course, if you have hand or arm motion from neurological causes, it corrects that too. IS pretty much doesn't know or care what causes shaking -- its an equal opportunity motion corrector :-)

[JDMvW]

Yeah, like Bruce and da rest sez. Same for VR on Nikon.

 

I generally (depends on the night before) have a pretty steady hand, but even the first generation IS let me get pictures I could not have got with even a much faster lens. The third generation doesn't need to be turned off for tripod use and can handle panning. Of course, despite claims to the contrary, it only handles motion on the camera/user end of the lens, not out there in the real world.

[mark_chappell]

<I>Earlier IS, like that in the big teles, supposedly needs to have IS turned off when the lens

is attached to a tripod.</i><P>

 

But they don't, even though this is contrary to the instruction manual. The superteles have a

tripod-detection mode; earlier IS versions did not. I have found from experience that even

the latest generation of IS (70-200/4 IS) should be switched off for very long (multi-second)

tripod exposures.

[winn]

When using my 70-300 on a tripod, it seemed to do better with the IS on. I don't know if I was picking up vibrations from the ground or when I realeased the shutter or if it is just my imagination...

[keith_lubow]

I have found (recently, upon first using IS in a real-world situation) that you have to let the IS settle before you take the shot, or it reduces sharpness very noticeably.

 

When it works, it works very well, but when it is not necessary, and you are not able to wait a few seconds before shooting, I would not use it.

 

For most things I shoot with this IS lens (journalism, events, candids, street pics), quickness of composition and timing of the exposure are critical. I can't wait for the IS to settle, so it isn't really that useful to me.

 

This is a 70-200 that I have long-term borrowed from a friend who [also] doesn't use it or like it.

 

Keith

[brucecyr]

"you have to let the IS settle before you take the shot"

 

Keith,

 

I've never noticed that in the lenses I mentioned. I didn't look for it, which probably means if it happened I would have tripped over it. In fact, I've never heard this complaint about IS or VR before. That suggests there may be something wrong with the lens you're using. If this were a regular aspect of IS shooting, I think we'd be hearing a load of complaints by now!

[winn]

"That suggests there may be something wrong with the lens you're using. "

Actually you are supposed to wait (I believe 1 second) for the IS to stablize. I'm sure this is included with the instructions that come with the lense. I've notice issues if I don't wait.