Canon EF 70-200mm f/2.8 L IS II USM Révision - Page 5
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Canon rates the Canon EF 70-200mm f/2.8 L IS II USM Lens' IS system for 4-stops of assistance. Testing
showed that I need a shutter speed of 1/80 to get a high percentage of sharp 70mm images with this lens. Turn
on IS and my shutter speed requirement drops to about 1/4 second which is slightly better than 4 stops of help.
At 200mm, my shutter speed requirements are 1/160-1/200 without IS and 1/15-1/20 with IS which is between 3
and 4 stops of help.
There is not a hard floor to the acceptable handheld-with-IS shutter speed used - but there is a diminishing return
in the results as the shutter speed lengthens. The example shots above were taken handheld/standing at
200mm with a 1/8 second shutter speed. The keeper rate is below what I'm comfortable with at these settings,
but if you take enough shots, you will likely get what you want. I have good 200mm results at even 1/6 second
but need to shoot about 10 shots for every good one. Note: Few awake people can remain motionless enough for
a sharp photo at these shutter speeds. Just in case you were thinking that.
The original 70-200 f/2.8 lens' IS was rated for 3 stops of assistance but the difference between IS on these
lenses does not stop with this number. The version II lens' more modern IS system is better behaved - more
stabile with less viewfinder jumping at startup. It is also quieter - almost silent aside from a little audible
start/stop sound.
IS is not a miracle for every situation - but I find it extremely useful. Aside from IS's obvious ability to allow
handheld shooting in low light situations, providing a still viewfinder makes critical framing easier. IS also
provides a steadier image to the AF and AE systems - allowing them to function more accurately.
The primary situation where IS is not helpful is when your subject is moving. Mode II (Panning Mode) IS is
available for controlling camera motion blur in one direction (great for tracking a vehicle or bike), but a moving
subject needs a faster shutter speed to stop the subject motion blur. Getting a faster shutter speed means using
a wider aperture or increasing the ISO setting. Using flash as a main light is also an option.
I seldom use IS when shooting sports and other action and always turn IS off when using a tripod (unless using a
super telephoto lens). Although IS is not really needed anytime a very fast shutter speed (an easily handholdable
speed) is being used, I seldom turn IS off for other purposes.
Unlike with precision image quality testing, event and most other typical uses for this lens rely on autofocus. The
Canon EF 70-200mm f/2.8 L IS II USM Lens is equipped with a very fast, quiet Ring USM (Ultrasonic Motor) AF
system. The II's AF is consistently very accurate. AI Servo AF performance is very good even with challenging
subjects incuding galloping horses.
www.the-digital-picture.com/Reviews/Canon-EF-70-200mm-f-2.8-L-IS-II-USM-Lens-Review.aspx
Canon EF 70-200mm f/2.8 L IS II USM Lens Review
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