Canon EF-S 17-85mm f4-f5.6 IS USM
 

Canon EF-S 17-85mm f4-f5.6 IS USM
I recently uprgaded to a Canon 50D with an EF-S 17-85mm f4-f5.6 kit lens included. Although I got a great price on the kit I'm not overly impressed with the results that the lens has produced, quite a lot of distortion at 17mm and fringing on verticals, when compared with my previous Nikon and Olympus kit. I'm thinking of changing it for something a bit better, hopefully!

Should I go for the EF-S 17-55mm F2.8 IS USM, EF-S 15-85 f3.5-f5.6 IS USM, or would I be better going for the EF 17-40 f4L USM. I'm unlikley to be upgrading to a EOS1 or EOS5 in the near future so the EF-S mount is not a problem. Any recomendations?

Thanks in anticipation.

The3dge!

have a look here .reviews of all possible Canon solutions.

If I had the money then it would be the 17 40 but then it would not overlap my existing lenses too much.

[url]http://www.the-digital-picture.com/R...ns-Review.aspx[/url]

It seems that you have done the sensible thing by looking into the future and deciding that you're not going to be looking for a FF body.

I think that I'd choose the 17 - 55mm f/2.8 for a few reasons. The fast f/2.8 aperture will allow you to introduce at least some background blur, whereas f/4 won't in most situations. f/2.8 allows twice the light to reach the sensor than the f/4 so you gain an extra stop. F/2.8 is the smallest aperture to be able to make use of the more sensitive centre focus spot.

The IS system on the 17 - 55mm gives you 3 more stops advantage, plus the wider aperture means a total of four stops advantage, well worth having!

Distortion at the wide end is still apparant at 2% but on the 17 - 40mm it's worse at 2.5% the lens you currently have set a new record (at the time) at over 4% Of course this is correctable in post processing, and the difference between 2 & 2.5% is not really going to be a deal breaker, but it is just another stat in the 17 - 55mm favour.

The 17 - 55mm also easy bests the 17 -40mm in resolution, being 25% better at f/8 this usually translates as sharpness. The extra 15mm focal length is also something not to be overlooked.

The only area where the 17 - 55mm loses out is vignetting, where because it is an EF-s lens compared to an EF one it's inevitable. Of course this is correctable in post processing.

Price is another issue, at £750 the 17 -55mm is much more money that the 17 - 40mm which costs £555. If you are prepared to use Ebay then you can pick one up for a similar price.

Digital picture does a lot of reviews of Canon lenses, but it's very subjective, and I find that he does tend to wear some strongly rose tinted glasses when it comes to certain lenses, I prefer photozone.de who test the lenses objectively, and have built up a pretty comprehensive list of lenses on Canon APS-c bodies.

Actually correction .........I would cut the bottom off a milk bottle and use that .

I would then look objectively at any prints ,view them under an electron microscope to check resolution and apologise to anyone who is so obsessed with resolution refraction diffraction for having the nerve to suggest anything at all.

sorry Flake I know you are knowledgable but you have a knack of belittling others posts in these fora .

Wasn't intended Matt, I trying to compare the two lenses that the OP had suggested, and to list the advantages & disadvantages. Your reasons for preferring the 17 - 40mm might come from a totally different perspective. You hadn't actually written much so I really didn't have anything in mind when I wrote my reply, other than the digital picture who in my opinion does present lenses in a more positive light than they sometimes deserve.

I find the 17 -40mm a frustrating lens, I'd love to buy one, but its poor corner performance on FF stops me.

The post wasn't written in any way as a response to yours, only as advice to the OP please don't take offence where none was meant.

fair enough