Good day to all! This is my virgin post in this forum. Nice to meet you!!


A little background of my hassle in struggling between EF 24-70 F2.8Land EF-S 17-55 F2.8 IS USM:


1. My body is 7D, and already has got a EF 70-200 F4 IS USM.


2. Needing a lens as my walking-around gear.


3. My primary subjects are my kids (who are always running around thus fast lens is needed) and family.


4. I do documentary shooting most (i.e. unposed pictures) and therefore again fast lens is prefered.


5. Indoor shooting all the time, so larger aperture is needed.


6. My personal preference is picture sharpness.


And here below are my concerns with the two lenses:


For 24-70:


i) It's heavy.


ii) I have seen some posts here saying 17-55 is sharper than 24-70 in all relevant range if using it in a crop body. Is that true?


iii) It's not wide enough if using it in my 7D. Might essentially need to buy another wide lens.


For 17-55:


i) Key concern is the build quality. People say it's good at collecting dust (though it won't really affect the image quality but still won't feel good about it).


ii) My brother has a 5D MkII. So 17-55 cannot be shared.


This is what I can think of now. At the moment, I feel I should get the 17-55, but I really hate the dust collect thing. And 24-70 really looks good with the red ring (opps, I know I shouldn't) though it's much heavier and being not wide enough in my crop body.


If anyone can throw me some ideas or hints, please do. Many thanks in advance!