This is the lens that I do 95% of my photography with. What people have to understand here is that there is some sacrifice when you have a lens that provides you such versatility. I have used this lens since 2003, basically traveling the world with it. What I have discovered, the key to keeping this lens in top notch working order. The day I open one out of the box, I totally tape up the top half of the lens with a strong gaffers tape. This is done to structurally keep the lens taught. This helps eliminate any torquing that takes place with day to day walking around with this on your shoulder. By doing this ad hoc tape job you will have to give up your manual focus option. I know this sounds bizarre, but its true. Also I never and I mean never, do I walk around with the lens extended to 24mm focal length, for this really adds stress to the lens. If you want you lens to maintain critical sharpness for years to come and if you use the lens daily, almost year round like I do. This will keep it sharp. I know many of my colleagues who after 1 or 2 months of heavy use complain that it is no longer sharp. I can actually keep mine going for up to 3 years with out having to have the lens serviced.
To view my work with this lens go to VIIphoto.com and look at my work. Like I said earlier 95% of it is done on this lens. Also my book "My America" was almost shot entirely with the 24-70, 2.8.
We do not live in a perfect world. But for me this lens comes quite close to being perfect. Minus the tape job.
Yours Truly,
Christopher Morris
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