I have been wanting a wide angle lens for sometime and have researched a lot of different sites and forums. For me price isn’t an issue as I am a firm believer that if you by the best lens the first time you will never buy twice and because I use it for work could justify the $1100 difference between the two lenses.
Anyway I bought the 17-40mm f4 lens for two main reasons over the 16-35mm. The main one being the 17-40mm lens takes a 77mm filter where the 16-35mm takes an 82mm. Big deal you may be thinking but for me this was the deal breaker. I really love shooting with my 10 stop ND filter and they arn’t available for the 82mm lens. Quite a few people on forums also put this as a negative and wished companies like Hoya and B+W made an 82mm 10 stop filter.
Another selling point for the 17-40mm for me was that at apertures of f11 and up the image quality is said to be equal to that of the 16-35mm, it is when the 17-40mm lens is shot at wide open that the 16-35mm is the far winner in image sharpness and contrast as you would hope and expect seeing you dropped the extra cash for the f2.8 lens. Seeing I don’t shoot at those apertures often I didn’t see the need to want this.
One thing I have found with the 17-40 that I believe is a trade off is that even when shooting at f11 and up in aperture at 17mm there is a small issue of fall off that is evident in certain lighting situations. But I knew this prior to purchase after reading the article on the Luminous landscape site. Though the article was based on the 16-35mm f2.8 Mark I not the Mark II lens.
I think in the near future I will own both lenses. 17-40mm for the long exposure shots and the 16-35mm for everything else. Maybe owning both is a bit excessive but for me at then end of the day I want the best lens that will get the job done at the exposure time I want and need for the look and effect in a shot.