09-16-2014, 12:18 PM
(This post was last modified: 09-16-2014, 12:20 PM by Brightcolours.)
This explains the extra weight:
400mm f4 DO:
![[Image: ef_400_4dois_usm_bd.gif]](http://www.canon.com/camera-museum/lens/ef/data/super_telephoto/diagram/ef_400_4dois_usm_bd.gif)
Orange = DO element
400mm f4 DO II:
![[Image: lens-construction.png]](http://cweb.canon.jp/ef/lineup/super-tele/ef400-f4-do-is-ii-usm/img/spec/lens-construction.png)
Yellow = DO element
Dark green = UD element
Light green = ground aspherical element
Overall, the amount of glass has increased.
About the price, yes it is very high. But the big ground aspherical element and the double glued DO element have very high production costs, though.
400mm f4 DO:
Orange = DO element
400mm f4 DO II:
Yellow = DO element
Dark green = UD element
Light green = ground aspherical element
Overall, the amount of glass has increased.
About the price, yes it is very high. But the big ground aspherical element and the double glued DO element have very high production costs, though.