17-55 f/2.8 IS..should I buy one?

ed rader wrote in post #3833799
the build isn't L either.

ed rader

Its better than L quality. It uses poly-carbonate instead of that old fashioned metal stuff for the lens barrel. L's are finally starting to catch up with the 70-200/4 IS.

Maybe I could pour some "sealant" around the top of the lens to keep the dust out..you know, the type plumbers use to seal against water leakage!!

Glenn NK wrote in post #3838044
As noted, there have been a few copies with dust problems. Also as noted, the dust doesn't seem to affect image quality.

I've looked carefully at my two Canon zoom lenses (24/105L and 17/55). The quality of the build is not the same; the 24/105 is obviously better built.

As for the dust situation, the major difference in the two lenses can be seen when one attempts to slip a thin piece of cardboard between the zoom ring and the barrel. On the 24/105, the cardboard stops very quickly against what feels to me like an O-ring, whereas on the 17/55, there is no seal, and the cardboard slides in easily.

A simple test was done by pushing a 1/4" (6mm) wide strip of light cardboard (really heavy paper) between the zoom ring and the barrel: On the 17/55 I was able to push it 1 3/4" (45 mm) into the lens. On the 24/105, the strip of cardboard won't even go in 1/8 of an inch (2 mm).

I just got this lens a little more than a week ago and no dust without a filter so far. I have one I intend to use but wanted to see if it built up during my "trial" period. I have used it indoors and out. I did the paper test on my lens and it doesn't go in more than the 1/8 inch GlennNK mentions on his 24-105. It feels like there is a foam seal from what I can tell. I wonder if maybe newer copies could have a seal system or was adjusted in some way? This is my experience anyway.

I've had this lens for like 5 weeks, it is the only lens I use on my 30D now. it is better than both the 24-70 and the 24-105 on my 30D, no question (to me) the best walkaround zoom for the 1.6x..... relatively small for a 2.8, Fast accurate and quite AF, Super sharp, "L" elements so contrast and colour are awesome and build is better than you'd expect from all the "dust" reviews (mine has none). Don't even think twice, just buy it.

I also just got mine a couple of weeks ago. But I also havent been shooting for very long so I cant really give an in depth review. It seems really sharp,and its definitely but I havent really had time to do any pp on any of my pics (been really busy since I got it). Since I spent all that money I will at least pretend like its the best investment I have ever made, at least until I really get the chance to prove it

I just recently rented this lens from Lensprotogo, and I LOVED IT!!! I don't think I can live without now. I had it mounted on my 30D, and it was just awesome. I may not have much experience with high quality lenses, but I can tell you it's on the top of my wish list. I was able to get some great shots with it while at the Nugget Rib Cook Off, and at a family members birthday. (Main reason I rented this lens)

where are you buying one for $1300? i'm looking to pick one up, or a 24-70/2.8. your prices sound good!

asxu wrote in post #3863826
where are you buying one for $1300? i'm looking to pick one up, or a 24-70/2.8. your prices sound good!

Discount Digital have them for $1299.00 but I will send you a PM and maybe we can work something out!!

Ron1004 wrote in post #3841519
I didn't apply new adhesive, but if needed, I would use that real thin mirror tape, which is what the original stuff looks like.

Ok, perhaps more for fun than anything, I took apart my 17-55 IS. It was just as that site said (was that your site, Ron?).

Easy peasy.

Just to add - It does help to have a pair of surgical forceps. I, too was a little nervous about keeping it open for too long. A majority of the dust (which was minor in my case) was on the back of the front element, possibly, because I keep this lens face down when I store it. The front 'seal' is very flimsy, and so easy to remove - it's basically an aesthetic label. There is actually a little hole just between where it says 'USM' and 'Canon', which i used to pry it off without going near the glass - I also used this to line up with the red hood mark.

Keep in mind, the orientation of the front element if you can - on the back, there is actually a kind of 'stepping' angular ring, so once you remove the three screws, you can keep rotating the front element anti-clockwise (I think), and while you do, it will rise up, but will hit a point every 120 degrees, where it seats in again. Each screw also has three positions it can sit in (total nine screw holes). I wonder if this is for calibration? I kind of kicked myself, because I only remembered very loosely which screw holes were used. When I think about it, though, can it be used to calibrate the front element? Consider that the front element doesn't rotate to focus, so it nearly doesn't matter which position it sits in...

Lol, I didn't seat it back in fully where it drops back - I *think* the screw holes I'm currently using are the correct ones when I undid it, so here's hoping it all works well, and I don't lose my front element down the track

It focuses beautifully at the moment.

tomsem wrote in post #3863408
I just got this lens a little more than a week ago and no dust without a filter so far. I have one I intend to use but wanted to see if it built up during my "trial" period. I have used it indoors and out. I did the paper test on my lens and it doesn't go in more than the 1/8 inch GlennNK mentions on his 24-105. It feels like there is a foam seal from what I can tell. I wonder if maybe newer copies could have a seal system or was adjusted in some way? This is my experience anyway.

A modification in the seals is quite possible.

Think about what all manufacturers say about "reserving the right to change features of a product at any time and at their discretion".

The only complaint I recall having read (other than one obvious nut case on FM that said it had terrible IQ) is that some copies of this lens have a dust problem.

I would be astonished if Canon, Nikon, and the rest didn't have staff dedicated to reading comments on the internet from users about their products. Since this comment has come up repeatedly, Canon may well have added a seal in more recent versions - and they are not obligated to mention this, and probably would not.

Hopefully no one doubts this - vehicle manufacturers have been making minor changes during a model year for years.

Ok, yes, I'm a nutter. One speck of dust in it, and I Just HAD to take it apart a second time. I also wanted to know what those angular steps were all about, so I did some test shots at different settings (no tripod, mirror -lock up or any of that nonsense, I just wanted to be quick). I think there's no difference in the position of the front element, in terms of focussing, but without proper tests, it's hard to be sure.

At any rate, I unmounted the 17-55 this time, and mounted the 60mm, and took some shots of it all apart (pretty much like Roger Cicala's page). I'll put up some pics soon.

mrkgoo wrote in post #3863896
Ok, perhaps more for fun than anything, I took apart my 17-55 IS. It was just as that site said (was that your site, Ron?).

No it's the OP's site.

I saw your other post with pictures, and your valuable comment to take note and mark the position of the front element and which of the three holes each of the three screws are in, to reassemble the same way.

I have opened mine twice. The first time I was away on a work assignment and didn't have the UV filter with me so it got another spec of dust, but since the second time I did the operation at home and immediately after fitted the UV filter mine has been dust free for some time.