In the past couple of weeks, we’ve seen a whole bunch of Canon lens patents surface, many of which showed updates of older lens designs with image stabilization added. Now two more have been unearthed by Egami, and Canon Rumors reported on them. One is for a variable aperture 17-55mm IS lens (not the f2.8 constant zoom), presumably another kit lens option to either replace or accompany the regular 18-55mm kit lens. The other is for a 70-400mm telephoto zoom lens, which Canon Rumors suggests may replace the current 100-400mm.
According to the patent description over at Egami, the 17-55mm kit lens option is pretty similar to its 18-55mm counterpart in both optical design and performance. One reason for making the wide-angle end a bit wider might be that Canon’s APS-C sensors use a 1.6x crop vs. the more common 1.5x crop, so 18mm really translates to a 29mm-equivalent, whereas 17mm on a Canon APS-C sensor would be closer to the 27mm-equivalent that 18mm is on a 1.5x crop sensor.
As for the 70-400mm, this patent might just show the successor of the current 100-400mm lens, which was previously rumored to be on display at this year’s winter Olympics in Sochi, Russia. However, Egami notes that the 70-400mm patent mentions a significantly higher number of lens elements compared to the current 100-400mm, which would make the lens much larger and heavier. Considering the size and weight of the current lens, it is unlikely that Canon will replace it with an even larger and heavier version.