I currently have a T2i and want to purchase a 6D. My 17-55mm is my favorite lens for the T2i but it will not work on the 6D. It looks like the 24-70mm will be very close to the 17-55 (27-88mm) but which one do I get? I really don't want to spend the $2,000 (give or take) for the 24-70mm f/2.8L II USM so I'm left with the EF 24-70mm f/4L IS USM ($1,200 used) or the a EF 24-70mm f/2.8 USM (used for about $1,000). I would consider the II USM if everyone believes that it is the only option but I can't see how I could justify a $1,000 difference in price. And while you're at it, is there really that much difference between the two two f/2.8's? Thanks.
Does Adorama still ahve the $1620 special on the 24-70 II? A few stores had them for that after special sale and mail in rebate and cash back deals ($1699 without the latter).
There is a huge difference between the 24-70 2.8 I and II (the new one also has a bit better AF, more noticeably so when paired with a 5D3/1DX that use the new ultra-precision mode it has, not sure if the 6D allows that or not though). The 24-70 f/4 IS is better than the 24-70 I too.
The Tamron 24-70 vc might be an option too, although that one I've never tried.
The 24-105 is far inferior to the 24-70 II and quite inferior to the 24-70 f/4 IS. Of course the price is far, far superior so it all depends on how much you have and what your priorities for spending are (and what they are for shooting too, if you just shoot centered subjects with the rest a blur and do it a lot hand-held at slow shutter speed the 24-105 IS might work out fine; if you love 24mm (where the 24-105 is not at its best) corner to corner with fine natural landscape details and shoot against bright skies at times and hate PF and so on the newer ones might leave you much happier; etc.) You can take plenty of awesome shots with the 24-105 and dont need anything else. That said, the others can deliver those shots in nicer technical ways, occasionally by a good deal. Some don't care about that, some do.