EF Mount APS-C Sensors to Become: "a curiosity of the past."

Y0GI wrote:

It's not likely that you'll see an EF-S 400mm lens anytime soon. I don't know the exact reasons why but while it is easy to build a short focal length lens, like the EF-S 18-55mm IS, smaller and lighter, the size differences diminish as focal length increases. Thus, the 'longest' telephoto lens in EF-S mount is the Canon 55-250mm IS lens. As the focal length increases, there is less and less of a size difference between EF and EF-S mount lenses.

--
Yogi
When you get down to the nuts and bolts of photography, the results depend on the 'nut' behind the camera!
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