Difference between the Kit lens and 17-40mm f4 L ?

[ianpaice]

My personal experiences are that the 17-40L focus fast and accurately. Somehow it feels more confident doing AF compared to 24-105L and 24-70L.

Hm. I've encountered problems with accurate focusing for quite a number of 17mm-xxmm zooms, particularly the Canon 17-55 f/2.8 IS USM and the Tamron 17-50 f/2.8. Both these lenses backfocused severely. However, at the tele end, the problem was not evident. I did not encounter this problem with the 17-40L that I rented to test over a weekend (mind you, over an entire weekend, not a couple of hours).

 

[thw]

Hm. I've encountered problems with accurate focusing for quite a number of 17mm-xxmm zooms, particularly the Canon 17-55 f/2.8 IS USM and the Tamron 17-50 f/2.8. Both these lenses backfocused severely. However, at the tele end, the problem was not evident.

Front/back focusing is something that can be resolved through calibration. (Of course, trying to get the Tamron calibrated will be a pain in Singapore since there isn't any Tamron service center.) I used to suffer severe back-focusing problems with my 17-85 IS lens on the wide end, but it was resolved after calibration.

The problems pointed out by Lightrules and Adam-T are NOT related to front/back focusing. It's hunting and refusal to lock at the right place under low-light.

I think many people are confused between (consistent) front/back focusing and inconsistent focusing.

 

[hazmee]

My personal experiences are that the 17-40L focus fast and accurately. Somehow it feels more confident doing AF compared to 24-105L and 24-70L.

I've had the same experience as well. My 24-70 is kinda 'slow' to AF when compared to the 17-40L. Weird... LOL!

 

[lightning]

I've had the same experience as well. My 24-70 is kinda 'slow' to AF when compared to the 17-40L. Weird... LOL!

you should try 16-35...AF is solid!

 

[rexscooby]

you should try 16-35...AF is solid!

solid but VERY expensive . Not enough vitamin M ...

 

[miniUltraman]

you should try 16-35...AF is solid!

I want!!! :lovegrin:

 

[miniUltraman]

My personal experiences are that the 17-40L focus fast and accurately. Somehow it feels more confident doing AF compared to 24-105L and 24-70L.

don't think I have much problem with 24-105L... I own a 17-40 b4 too.. Can't really differentiate the focusing speed between them.. at least unnoticeable to me :think:

 

[lightning]

solid but VERY expensive . Not enough vitamin M ...

Save Save Save then Buy Buy Buy.....I actually bought some endowment (5 years) plan few years back, $200 a mth,so that I can buy what I want now Better then put the money in bank. End of 5 years I get the full principal and some interest...better then what the bank gives me. In case I konk out, my family get some extra money too. Now I am thinking of putting into unit trust, 5 years down the road should be able to get some good returns back.

 

[ianpaice]

In absolute figures, the 17-40 will definitely be faster since it has a shorter focal range. But the AF of 17-40 is like so swift and precise that give you the feeling "it stops on a dime"

don't think I have much problem with 24-105L... I own a 17-40 b4 too.. Can't really differentiate the focusing speed between them.. at least unnoticeable to me :think: