Thank you! There are so many replies, I'll try to read and comment on all


cian3307<span class="ForumPostTitleDate"]replied onTue, Oct 27 2009 5:46 PM



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I have the 17-40L and find it a superb lens. However, there are times when the IS would be useful....


It's going to be a matter of personal preference that decides it for you.



I don't doubt the quality of this lens, although I'm a bit afraid of it's sharpness. That's the only downside I can think of right now. As I mentioned, I mostly shoot sports and outdoors and IS is something I never used and I probably will never use. Unless it is IS panning mode, but both lenses lack that feature.



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<div class="ForumPostTitleInner"][b][url="http://community.the-digital-picture.com/members/Sean-Setters/default.aspx]Sean Setters[/url][/b]<span class="ForumPostTitleDate"][url="http://community.the-digital-picture.com/forums/p/2430/18814.aspx#18814]replied on[/url]Tue, Oct 27 2009 6:19 PM
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Those of you who've read my posts know that I absoluetly love my 17-55 f/2.8 IS. It's probably the best all-around general purpose lens with superb image quality (that is, on a 1.6x body). However, I'm unsure that the 17-55 will be a cure-all for Sheiky. The reason is simple--the 17-55, in my opinion, hunts for focus a little to often in low-light situations. I've run into this problem on several occasions where I simply couldn't obtain focus even though I thought there was enough ambient light to do so.


Therefore, in this situation, with the poster's specific needs in mind, I'd be inclined to suggest the two-lens setup. However, my best advice is to save up a little extra money and rent the 17-55 first. If it focuses well enough in low light situations for your needs, then buy it--it's a more useful lens than the 17-40. However, if you find that it doesn't focus well enough in low-light situations, thenrent the 50 f/1.4 and see if it will perform up to your standards under those same conditions. If so, then buy the 17-40 and 50mm combo.



[b]Alright, that's a clear point. Unfortunately I can't rent the lens at my local store. I could take it out for testing outside with a salesman for max 30 minutes. That's the only choice I have. I will definitely do this with both lenses on D-day I can try lowlight focussing indoors there to find it out myself. Thank you for pointing that out.[/b]



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<div class="ForumPostTitleInner"][b][url="http://community.the-digital-picture.com/members/Daniel-Browning/default.aspx]Daniel Browning[/url][/b]<span class="ForumPostTitleDate"][url="http://community.the-digital-picture.com/forums/p/2430/18810.aspx#18810]replied on[/url]Tue, Oct 27 2009 7:16 PM
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<blockquote>
<div>[b]Sheiky:[/b]</div>
<div>I liked the imagequality but the longer I used it the more I hated the af performance, speed and accuracy, especially in low-light and or party-environment.</div>
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My experience is that the 17-55 is not going to do any better with autofocus. It will be quieter is all. I think upgrading from your 50D to the 7D would make more difference to autofocus.



<blockquote>
<div>[b]Sheiky:[/b]</div>
<div>I can't decide between the canon 17-40L and the 17-55 is usm</div>
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There's no contest. The 17-55 destroys the 17-40 in almost every category. The only superiority of the 17-40 is in the weather sealing, build quality, and full-frame compatibility.


If your whole reason for upgrading is autofocus, then the 17-40 would be a huge step backwards. It does not even activate the f/2.8 autofocus sensor in your camera, which is far more accurate than the f/5.6 sensors that the 17-40 uses.



<blockquote>
<div>[b]Sheiky:[/b]</div>
<div>-sharpness: I hear a lot of different opinions about this matter. Some say the 18-55 kitlens even outperforms the 17-40. That's hard to believe for an L lens. So I hope you can clear this for me. I really like detail and sharpness. I'm used to watching my photo's at 100%</div>
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It's true. The cheap, lowly 18-55 kit lens blows the 17-40 out of the water:


[url="http://the-digital-picture.com/Reviews/ISO-12233-Sample-Crops.aspx?SampleComp=0&amp;FLI=0&amp;API=1&amp;Le ns=455&amp;Camera=474&amp;FLIComp=0&amp;APIComp=0& amp;LensComp=100&amp;CameraComp=474]18mm at f/4.0[/url]


[url="http://the-digital-picture.com/Reviews/ISO-12233-Sample-Crops.aspx?Lens=455&amp;Camera=474&amp;Sample=0&am p;FLI=1&amp;API=0&amp;LensComp=100&amp;CameraComp= 474&amp;SampleComp=0&amp;FLIComp=2&amp;APIComp=0]24mm at f/4.0[/url]


[url="http://the-digital-picture.com/Reviews/ISO-12233-Sample-Crops.aspx?Lens=455&amp;Camera=474&amp;Sample=0&am p;FLI=2&amp;API=1&amp;LensComp=100&amp;CameraComp= 474&amp;SampleComp=0&amp;FLIComp=3&amp;APIComp=1]28mm at f/4.5[/url]


[url="http://the-digital-picture.com/Reviews/ISO-12233-Sample-Crops.aspx?Lens=455&amp;Camera=474&amp;Sample=0&am p;FLIComp=4&amp;APIComp=2&amp;LensComp=100&amp;Cam eraComp=474&amp;SampleComp=0&amp;FLI=3&amp;API=2]35mm at f/5.6[/url]


The other cheap lenses are even better. Your previous Tamron 17-50, or the Sigma 18-50, and of course the Canon 17-55 all do better than the kit lens, so they are in a different league than the 17-40.


It should not be surprising or hard to believe. The 17-40 is like a big commercial truck that can carry 30,000 pounds at 60 MPH. The 18-55 IS kit lens is like a small sedan. It can drive twice as fast as the truck (60 MPH), but it can't tow 30,000 pounds. It is much sharper than the 17-40, but it can't be used on full frame. The 17-55 f/2.8 USM and Tamron 17-50 are like sports cars. They drive even faster than the 18-55 kit lens, but they still can't be used on full frame.


If you want to see the 17-40 shine, you *have* to put it on full frame. Compare the 17-40 on full frame vs. the 10-22 on APS-C and you'll see what the 17-40 was designed to do.


[b]Alright this is a clear and helpfull comment. I checked out the isocharts or whatever they are called and I've seen the differences .... WOW! If every 17-40 is that "sharp" I'll definitely NOT buy this lens :P[/b]



[b]The problem with autofocussing on the Tamron was that sometimes it's just to slow. Imagine an athlete running towards you or people on a trampoline. It just couldn't get the focus right 1 out of 2 times. Sports photography is a discipline I do most, so this is a major issue for me. My 70-200 never let me down on this one. And that lens is "just" f4. On the back of my camera most of those pictures looked fine, but when I watched them fullscreen I'm disappointed half of the time. That's why I wanted something faster. I'm convinced that the usm feature focusses a lot faster and more accurate.[/b]


[b]Upgrading to a 7D is a future dream I'm using my 50D for like half a year now and I'm really pleased. Especially compared to the 450D which I had before it.[/b]



<div class="ForumPostTitle"]
<div class="ForumPostTitleInner"][b][url="http://community.the-digital-picture.com/members/Chuck-Lee/default.aspx]Chuck Lee[/url][/b]<span class="ForumPostTitleDate"][url="http://community.the-digital-picture.com/forums/p/2430/18810.aspx#18810]replied on[/url]Tue, Oct 27 2009 11:21 PM
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<blockquote>
<div>[b]Sheiky:[/b]</div>
<div>About a week ago I decided to sell my tamron 17-50 2.8, because I was tired of it. I liked the imagequality but the longer I used it the more I hated the af performance, speed and accuracy, especially in low-light and or party-environment.</div>
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I hope "decided" doesn't meant you did. The 17-50 f2.8 is an great piece of glass.


Low light parties are sometimes too low light even for the best L glass with USM. I'm still confused as to why people always want to blame it on the lens. I get more hunting with my 70-200 f2.8L in a low light situation than I do with the Tamron 17-50.


Primes are great for low light. I love the EF 50 f/1.4 @ f/2.0 for low light indoors work. That however is on A FF 5D. Maybe someone knows of a high quality 30 or 35 1.4 that would fit the low light party need of a APS-C sensor.


Sheiky, I think you'll find when shooting in low light with low number apertures AF will always be hit and miss. The dof at f2.8 and below gets very narrow and just a little movement toward or away from the camera can cause an OOF result. IMHO, I would suggest if you buy something that you would put it in a head to head test with the Tamron before selling that lens off. You might be suprised at the test results. It could save you some considerable coin.


Otherwise, I vote for the 17-55 f2.8 IS.


The last consideration is to buy a 430 EX II andshoot bounce flash. The external will give you focus assist in low light and with flash you can shoot at higher apertures resulting in sharper more "in-focus" images. If you feel like flash is to intrusive, set the flash not to fire and just use the AF assist.


My thoughts, good luck.


[b]Thanks. I already have the 580EX II flash, but low light isn't really my problem. I know it's hard for every camera/lens to find a good focus. It's more the problem I stated a few lines earlier. The "slow" focussing is the problem for me.[/b]



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<div class="ForumPostTitleInner"][b][url="http://community.the-digital-picture.com/members/gunslinge/default.aspx]gunslinge[/url][/b]<span class="ForumPostTitleDate"]replied onWed, Oct 28 2009 12:03 AM
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This is bad, this summer I could not make the same choice, so I got the tamron 17-50 2.8, because of the cost and its 17mm was to be wider that the canon's 17mm, and have been very happy with it, except for some back-focusing at very close range. You seem very well informed about the choices, have you looked at the new EPS 15-85 ( I think that is the right model ), wider on both ends, IS, somewhere inbetween for cost, and a little slower F-stop wise?


Hey man, well this isn't really bad is it?? I hope not :P The Tamron is a really good quality lens. It's just that I'm not pleased with the focussing during sportsphotography. I don't really experienced backfocussing at very close range. For portraits I use my 100mm lens as well for close-ups of other things.


I have noticed the new canon lenses, but I'm not really warming up for them. I just like the fixed aperture. I shoot a lot in the Manual modus so an aperture depending on the zoom could really screw things up for me.


I'd like to thank you all so far for your good and upbuilding comments. They really help. I'm still not really convinced but I'm leaning towards the 17-55 at the moment, because of sharpness issues with the 17-40. I think it's hard to believe that an L-lens gets beaten in image quality by a standard kit-lens. I was dreaming/hoping that someone with a 17-40 could post me some photo's proving that sharpness is not such a problem :P Thank you all so far. I will edit my startpost with the things you mentioned.