17-40L - any easy way to check focusing?

Raider · 4 Jul 2006 at 16:40

I received my 17-40L last week, but so far i've been disapointed with the sharpness. My 70-200mm F4 L seems to have it beat hands down.

I may be wrong, but the focusing seems to be a little off. Despite good light at the weekend, I haven't taken a photo with the lens that makes me say "Wow!"
I try to use the lens at F5.0 rather than wide open, but still I'm thinking that I haven't got much for my £450.

I'm guessing I should try and take a few photos of a single object with both the 17-40L and 70-200L, and compare them. If this lens can't perform then it'll have to go

Raider · 4 Jul 2006 at 20:26

Ok so maybe I shouldn't expect so much from the 17-40L?
Stopping down to F5.6 or F8 will sharpen it up nicely, but that gives a huge DOF, which isn't always useful for an all-rounder lens.

How does the 24-70L compare in terms of sharpness wide open (F2.8)?
If it was a big step up, then i'd consider ditching the 17-40L in favour of the 24-70L in order to get a nice DOF, and sharper images.

Raider · 4 Jul 2006 at 20:52

Maybe I should keep my Sigma 10-20mm, and go with the 24-70L.

Will have to swap lenses for wide work (quite rare), but it'll be useful having the extra 40-70mm range on the same lens!

Raider · 5 Jul 2006 at 09:34

For £750 I could get the 24-70L F2.8, which would probably be a better buy!

Raider · 6 Jul 2006 at 10:20

Well it looks like my 17-40L is absolutely fine focus wise. But the sharpness is just a bit of a let down compared to the 70-200L.

Looks like i'll be selling it though to fund the 24-70L F2.8 instead. Gah that makes 3 L glass purchases in a month :eek:

Raider · 6 Jul 2006 at 13:50

A random name said:
From what i've read, the 70-200 F/4 L is the sharpest L zoom going... So you're going to be dissapointed with any lens to be honest.

Yeah I know. Gah I hate having to pick lenses. I have a real kit bag crisis atm

Maybe the Tamron 18-50 F2.8 will fit the bill.. if somebody in the UK had some!! :mad:

Raider · 6 Jul 2006 at 14:27

A random name said:
You looked at the sigma 18-50 f/2.8 sigma? Supposed to be tack sharp that lens.

Hmm i've heard quite a few bad things. Usual Sigma issues with quality control.