15-85 on 7D - how's the quality compared to 24-105 on 5D2?

I'm considering beefing up my APC system a bit more and that means the search for a good standard zoom continues. The 17-85 IS, while having served well, is starting to show its limitations.

I'm used to a 24-105 on 5D2, and it is superb, so I am wondering whether the 15-85 would deliver similar quality on the 7D. For purposes of this discussion, we can discount the following (just to stay on track )
- Third party (not interested, no matter how many rant about it, not interested. Beentheredonethat, sold them all. Sorry. Tried and found wanting.)
- 17-55 f/2.8 IS should be left out of this discussion. That lens and I have a grudge against each other. It doesn't like me, I don't like it, and I won't touch it. Yes it's personal
- Why I need a 7D in addition to a 5D2. Because Canon does not make a 14MP, 8fps full frame body. As for WHO makes such a camera, it may be wiser not to ask, though the answer is easily found

So with that in mind....post away.... if the 15-85 can get close I woud consider it.

PS: image quality only. I am aware the aperture of the 15-85 is slower - that testing's been done and I have found workarounds. f/5.6 won't kill me

As you say the 15-85 is slower, and obviously hte build wont be as nice as the 24-105L. However, optically the 15-85 is very very very good, at least my copy is. every shot, wide open even, gives me amazing sharpness as well as contrast and color saturation. The first time I took this lens out it took my breath away with its color saturation etc. and made me immediately glad I chose this one.

However it does have its quirks that you should know about before buying.

1. Vignetting, this lens vignettes A LOT wide open. It is easily fixed by stopping down, if you shoot JPEG with peripheral illumination, or on PP but it cant definitely be a bother.

2.Distortion. Personally the distortion for me is very tasteful and gives it the wide view feel that I was looking for, however if you are planning on shooting architecture at 15mm..... not the right lens for it. after getting to 24mm the distortion is gone and at 85 I haven't noticed any but I've heard there is some pincushion distortion.

3. This may or may not bother you, there is a bit of Lens Creep, what can we say, its a heavy lens with a dual cam design.... once you get to about 30mm if pointed straight down it will creep to about 50mm, and pointed up from 50 to about 24mm. Honestly other than bothering me because I am looking for it this has not been a problem at all...

the build of this lens is very nice for an EF-S and beats alot alot alot of lenses. it feels solid and that gives confidence. It balances very well on my gripped t1i so I'm guessing it'd do the same if not better on a 7D! The AF is very VERY VERY accurate even in low light. I did a photo shoot at a very dim train station at 12:30am, (I know, sketchy)... My strobes that I was using do not have AF assist, nor modeling lamps, so the T1i and this lens was had very little light to utilize and it locked focus very VERY quickly every time which made it possible to get the shots I needed. the IS system also works very well and the range is amazing for the quality of pictures you get.

I love this lens, and am VERY glad I bought it... the only time it has been off my camera in the last month (since I got the lens) has been for comparisons between 15mm and 18mm (and it is a huge difference)

hope that helps!

I have several L lenses, but I keep a 15-85 on the 7D as a general purpose lens. It is about as equivalent to a 24-105 on full frame as you can get from a 1.6X crop body. From the sound of the OP's post, seems like a good option.

Sounds good might give it a try!

I purchased the 7D and 15-85 a few months ago in preparations for my sisters wedding in Italy last month. I was really pleased with the performance of both, although I could have used a faster lens in the church since it was so dark but even at ISO 3200 (first shot, below) I was pleased with the result:

Thanks guys, the feedback is appreciated. I bought the lens and it is tremendously impressive. This is coming from someone who's as L-coholic as it gets. The 7D also demands a whole lot from the lens, exposing flaws that you wouldn't have seen on earlier cameras.

Glad to say the 15-85 is every bit of what I hoped. Sharp enough wide open at every part of the focal length. AF, IS, USM, all up to expectations. Zoom ring is nicely weighted and almost completely even throughout the focal range (although requires just a tiny bit more force in the center). PIC on 7D completely cures vignetting problems, distortion is only noticeable when I shoot geometric patterns. Yes it is a bit of a 'moustache' distortion that's harder to fix in post, but some compromises are acceptable, IMO.

Does it compare to the 24-105 on 5D2? Absolutely, disregarding the aperture which is already a known consideration (if you need constant f/4, look elsewhere).

Colors and contrast, are all there. Good stuff.

Build quality is very decent though I still think the L's are a bit better.

Appearance? No, it's not as 'ugly' as I've heard it been called. This is actually not much of a consideration, but I just thought I'd mention it. If I wanted good looking, I would pack the 200/2.0. The 15-85 is nicely understated and goes very well with the 7D's appearance.

Methinks....I like this lens

Thanks to all for the above posts. I'm now sure I'll get a 15-85mm.

For a while, I've wanted to upgrade to from my EF-S 18-55mm IS kit lens (which I find increasingly poor optically). I originally thought the 17-40L would do the trick for my EOS 400D - and I could continue using it if I upgraded to a full frame camera body. But I decided its zoom range is a bit short for a general purpose/walk around lens, and this limitation would be worse on a full size body. Other options were:

• 17-55mm IS -optically excellent but 50% more expensive
  
• 24-105mm - not wide enough on APC body
  
• 17-85mm - optically inferior to the 15-85mm

At first I figured I would leverage my 17-40 to do the job as well, but the lack of IS and the range really killed me in production. I'm one of those folks who uses IS as a creative tool, and not just for shake reduction. Tech creates new opportunities.

17-85 is optically disappointing. It was fine five years ago when I bought it. It isn't now.

If you have no DEFINITE plans to go FF, go with the 15-85. By "definite" I mean you have a date or at least a good idea of the timeframe when you are confident that you will buy a non-EF-S camera.