William Robb wrote:
----- Original Message ----- From: "Jostein"
Subject: Re: Temporarily enabled with 2.8/70-200mm
Very true. However, the Canon EOS lenses does not have an aperture
ring, and neither does many nikon lenses. I don't know exactly why C
and N have eliminated them, but it could be a sign in time for the
future of the K-mount.
Canon removed the aperture ring when they went to the EOS system
because they came up with a 100% electronic interface between camera
and lens. The aperture is driven by an electric motor, not a spring.
The Canon rep told me (sorry, not compelling evidence, just anecdotal)
that they felt accuracy and reliability would be improved by
eliminating moving parts, as much as possible, and that in the long
run, it would be cheaper for manufacture and, consequently, for the
consumer to purchase.
I don't know about Nikon's reasoning, but it is probably similar.
William Robb
Nikon's was pure cost reduction, as only the meter coupling was
eliminated, the aperture stop-down is still mechanical, just like on the
DA and FA J lenses from Pentax. It does make for a good compatibility
differentiator for VR lenses, as VR compatible bodies all set the
aperture on-body anyways.
-Adam
