06-08-2012, 12:04 PM
[quote name='Brightcolours' timestamp='1339153014' post='18770']
I am not too surprised about that... It is the only STM zoom they offer. If they want to make a big point of the hybrid AF system for live view, it is the only option, and it would be stupid to have the only option have the not so great performance of the old 18-135mm.
The optics have changed quite a bit:
Old 18-135mm:
![[Image: lens-construction.png]](http://cweb.canon.jp/ef/lineup/ef-s/ef-s18-135-f35-56is/img/spec/lens-construction.png)
New 18-135mm STM:
![[Image: lens-construction.png]](http://cweb.canon.jp/ef/lineup/ef-s/ef-s18-135-f35-56is-stm/img/spec/lens-construction.png)
[/quote]
Maybe one reason for the substantial redesign was the need to have minimal mass (small lens/lens group) for focusing, like in the case of the Olympus redesign that you posted in the other thread http://www.olympus.com.au/Learn---Explor...ology.aspx
Alas, no information given here which parts are moving during focus.
I am not too surprised about that... It is the only STM zoom they offer. If they want to make a big point of the hybrid AF system for live view, it is the only option, and it would be stupid to have the only option have the not so great performance of the old 18-135mm.
The optics have changed quite a bit:
Old 18-135mm:
New 18-135mm STM:
[/quote]
Maybe one reason for the substantial redesign was the need to have minimal mass (small lens/lens group) for focusing, like in the case of the Olympus redesign that you posted in the other thread http://www.olympus.com.au/Learn---Explor...ology.aspx
Alas, no information given here which parts are moving during focus.