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
Filing Date: 2008/07/02
Focal length f = 17.50 ~ 53.05mm
Brightness F = 2.0
Focus back 34.90 ~ 48.26mm
Focal length f = 17.50 ~ 52.36mm
Brightness F = 1.8
Back Focus 34.15 ~ 45.06mm
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
Placement of the lens to optimize the refractive index
I've looked quickly, but I haven't been able to find the actual patent anywhere. Can anyone else?