EF-S 17-55 Replacement Coming?
A patent has been discovered showing the existence of an EF-S 17-55 f/2 IS lens.
Canon EF-S 17-55 f/2 IS
Patent Publication No. 2010-14866
Published 2010/01/21
Filing Date: 2008/07/02
Example 1
Focal length f = 17.50 ~ 53.05mm
Brightness F = 2.0
Focus back 34.90 ~ 48.26mm
Example 2
Focal length f = 17.50 ~ 52.36mm
Brightness F = 1.8
Back Focus 34.15 ~ 45.06mm
General
Zoom is easy to increase the rate
Increase the amount of movement of the lens
But more aberration
Large diameter is easily
To compensate by increasing the number of lens aberration
But heavier
Patent literature
Placement of the lens to optimize the refractive index
Aspheric lenses
From Here: http://egami.blog.so-net.ne.jp/2010-02-08#more
CR's Take
I've looked quickly, but I haven't been able to find the actual patent anywhere. Can anyone else?
Thanks Justin
74 Comments
Wow, thanks for taking the time to test this lens for us. Hats off to you.
Oh yeah, since the current 1-kilogram 24-70 w/o IS is still too light for daily use. 24mm on a crop cam would be ~38.4mm, not really that much of a wide angle. EF-S lenses are there for a purpose.
Yet another FF snob.
You wouldn’t wet yourslef if this was FF becuase it would never happen with FF.
Anyone a ideal what the price range 16-55 f2 will fit?