Does 11mm make much difference

I have a canon 28-105 but am looking at a 17-40. I have a 1Dmk2 and a 20D and was wondering if 11mm from my 28 to a 17 will make much difference?

Huge ...

The 17-40L on your 1DII will be nice and wide and weatherproof.

Look at some of your pics and the exif info, that is the only way to tell if the extra few mm are really important for you. I was thinking of getting the 28-105 for my walk around, but when I looked back at my pics, about 10% of them were in the 17-24mm range, which was more than enough to make me reconsider. If you look back and only a handful of pics are in that range, you may be better served with something else.

ICee:
The 28 on your 1DII(1.3X) is equivalent to a 36 on a full frame/film body.
The 17 on your 1DII(1.3X) is equivalent to a 22 on a full frame/flim body.
14mm is a big difference.
The 24-105L is probally the most recommended 5D zoom lens, and you will be 2mm wider, wide enough for acceptable landscapes.

vic6string wrote in post #3235489
Look at some of your pics and the exif info, that is the only way to tell if the extra few mm are really important for you. I was thinking of getting the 28-105 for my walk around, but when I looked back at my pics, about 10% of them were in the 17-24mm range, which was more than enough to make me reconsider. If you look back and only a handful of pics are in that range, you may be better served with something else.

this makes a lot of sense. most of my daily shooting involves only from 28mm up. i hardly use my wide angle unless required, or on holidays.

ICee wrote in post #3235330
I have a canon 28-105 but am looking at a 17-40. I have a 1Dmk2 and a 20D and was wondering if 11mm from my 28 to a 17 will make much difference?

Massive difference - if you had a kit lens you'd know.

the 17-40 is one of the best Canon make, and it will fit both your bodies, unlike the kit lens, and further more is optically of a standard to help show your 1 series at its best.