You too? I was wondering what that switch might be. I was thinking IS, but that would typically be next to the AF/MF switch, at least on most zooms anyway. A zoom lock switch might be more realistic, but who knows.
The hood bayonet is at the front of the lens, not at some collar placed farther back towards the imaging plane. Unless they've got some funky hood design that I'd love to see, as it would have to accommodate both wide angle and telephoto, I'm not sure that the front of the lens extends.
At least, based on speculative images like this.
If it were an internal zoom it would be the cat's meow.
Tom K. wrote:
Why would it need a zoom lock switch? The 24-70 version 1 didn't need it.
I can think of a few reasons:
This lens will extend significantly, since it uses an optical layout ("positive-lead" type) that requires that.
Since it uses positive-lead type optics, the front group of elements is very large and heavy, and therefore acted upon more strongly by gravity.
The new design translates a small movement of the zoom ring into a large change in length at the wide end of the range (that's why the focal lengths are tightly bunched up at the wide end); said another way, gravity has a large mechanical advantage in extending the zoom at the wide end. This means it will likely flop out to say, 35 mm, with relatively little force (especially after a few years of use!).
When extended, the total length with hood will increase, whereas the old lens was shrouded in a fixed hood so didn't increase in overall length; it's therefore more important that this new lens doesn't extend by itself.
The new construction may use more plastic (maybe even the extending barrel?) to reduce weight and cost, which may take its toll on snugness.
This lens will extend significantly, since it uses an optical layout ("positive-lead" type) that requires that.
Since it uses positive-lead type optics, the front group of elements is very large and heavy, and therefore acted upon more strongly by gravity.
The new design translates a small movement of the zoom ring into a large change in length at the wide end of the range (that's why the focal lengths are tightly bunched up at the wide end); said another way, gravity has a large mechanical advantage in extending the zoom at the wide end. This means it will likely flop out to say, 35 mm, with relatively little force (especially after a few years of use!).
When extended, the total length with hood will increase, whereas the old lens was shrouded in a fixed hood so didn't increase in overall length; it's therefore more important that this new lens doesn't extend by itself.
The new construction may use more plastic (maybe even the extending barrel?) to reduce weight and cost, which may take its toll on snugness.
