From Imaging Resource & SLRGear
The folks at Imaging resource have come up with their own way of testing the effectiveness of image stabilization in lenses. There first test subject? The 70-200 f/4L IS.
There is all sorts of charts and graphs and fun stuff to read.
The Verdict? At best, the 70-200 f/4L IS came away with a maximum improvement of 2.8 stops with IS turned on. That's pretty impressive. Canon claims “4 stops”, but we all know about the validity of manufacturer claims.
Yes, you'll get 30mpg if you're driving down a hill, newly paved, with the wind behind you on racing slicks and the engine off.
I'd like to see a good comparison of this lens and Sony's 70-200. What's better, in-body or in-lens? Get it done IR!
Read More: http://www.slrgear.com/…
cr
11 Comments
Well actually racing slicks are very bad for fuel economy: too sticky. For best fuel economy you want highly inflated hockey pucks from WalMart: low rolling resistance. Of course you’ll be killed at the first corner.
I thought this was a rumor site and not a review site.
LAME
@Nyc
I find non-rumor related posting useful, in particular in more dull times. I guess I wouldn’t have stumbled across the SLRGear IS review otherwise.
Regarding the effectiveness of the IS in the EF 70-200 F4 IS… I have that lens, and while I am happy with its image quality and AF performance, I actually — subjectively — felt that the “Vibration control” (VC) of my Tamron 28-300 VC “superzoom” is noticeably more effective. I hope SLRGear will test mor IS/OS/VC/VR implementations soon.
I can’t give you any estimates in F-stops, though — in particular because most of my non-keeper shots with the Tamron are due to its terrible AF accuracy. Mine has a serious problem on close range subjects in the 28-45mm focal range.
Having owned this lens since its introduction, I would agree in general that 4 stops stabilization is optimistic. That’s not to say it isn’t possible, just that in regular use I’ve found this lens has been less consistent than what I came to expect from the 2.8 IS version (though it’s not even close enough of a reason to switch back to the 2.8 IS).
A possible explanation for the less effective IS could be that the lens is not as massive as the 2.8 version, yet just about as long, resulting in a combination that is lighter in the hand with less inherent “natural” vibration suppression, forcing the IS system to work harder.
anyone who’s arguing racing slicks and the sound of one hand clapping is missing the point of the analogy. analogies are inherently flawed, but the point remains… that manufacturer claims are often optimistic at best.