Taking apart the EF 16-35 f/4 IS (image courtesy: R. Cicala/Lensrentals)
The weather sealing appears to be pretty good (better than usual). The article is long and comes with lots of pictures shot while disassembling the EF 16-35 f/4 IS. R. Cicala writes:
Now that I’ve seen the insides I’m very optimistic that this lens will be less likely to deteriorate optically over time, and will be more easily corrected when it does.
Canon EF 16-35 f/4 IS price check: [via lensrentals]
Image from Canon’s White Paper (note that the aperture is also moving)