Is this chromatic aberration due to a faulty lens?

[valdore]

I rented a Canon 16-35 L f/2.8 ultra-wide angle lens at the rate of $40 per day. Can some of you verify for me that this is too damn much chromatic aberration lining the side of the skyscraper for such an advanced lens?

I'm thinking some prior renter of this lens was a dope and played frisbee with it or something. I have to return the thing tomorrow morning and pay up, and I'm trying to figure out if there's something to this or not. It also vignettes excessively in the upper right and left corners, even on my full frame 5D.

Advice appreciated.

 

[valdore]

Also worth noting, there was a UV Haze filter attached to the lens that I never removed when taking shots with it, but surely that wouldn't cause vignetting and chromatic aberration would it?

 

[Phrasikleia]

Chromatic aberration seems to be the Achilles heel of that particular lens. See the review and chart here:

http://www.slrgear.com/reviews/showproduct.php/product/1082/cat/11

A good chart would look something like this one. An insanely good chart would look like this one.

 

[toxic]

I rented a Canon 16-35 L f/2.8 ultra-wide angle lens at the rate of $40 per day. Can some of you verify for me that this is too damn much chromatic aberration lining the side of the skyscraper for such an advanced lens?

the original 16-35 wasn't a very good lens. this is one of the reasons why. if this was actually the 16-35 II...then either it's a bad (or abused) copy, or that was a pretty high contrast edge. also keep in mind that ultrawides have trouble with CA in general.

It also vignettes excessively in the upper right and left corners, even on my full frame 5D.

just in case, you didn't know, all lenses vignette more on 35mm sensors than APS-C ones.

a UV filter may have made the CA even worse. maybe vignetting as well? i'm not that familiar with ultra-wides.

 

[anubis]

Wow, that's bad. CA shouldn't be more than 2 pixels in width max. That thing's definitely a bad copy. This is according to photozone.de tests

It also vignettes excessively in the upper right and left corners, even on my full frame 5D.

This statement doesn't make any sense... we would expect a higher degree of vignetting on a full frame sensor compared to crop, because full frame goes much closer to the edge of the lens image circle

 

[miles01110]

Ick... that's terrible. Definitely the lens.

 

[valdore]

This statement doesn't make any sense... we would expect a higher degree of vignetting on a full frame sensor compared to crop, because full frame goes much closer to the edge of the lens image circle

I had figured since I have no vignetting problem when I put my own 15 mm Canon fisheye lens on the 5D that there would certainly not be a vignetting problem when we're talking about a 16 mm minimum focal length. Doesn't something seem to be awry here? And why is it vignetting at the top but not the bottom?

And I just looked, it is indeed the original version, not the II. And that sucks. I like my 17-40 f/4.0 a lot better and it's half the bloody price, but unfortunately I have to send it in to Canon for a repair.

 

[leighonigar]

Do take a couple of shots without the filter, just in case it is the filter encroaching. I'm unfamiliar with the lens so can't comment on the CA.

 

[valdore]

Do take a couple of shots without the filter, just in case it is the filter encroaching. I'm unfamiliar with the lens so can't comment on the CA.

I will. Although I just returned the lens for my allotted rental period, I'm checking it out again for the weekend. I'll try that.

The conversation I had at the lens rental place indicated there's quite a bit of stuff I'm unaware of concerning lens construction. I guess I know apertures and that's it.

 

[toxic]

I had figured since I have no vignetting problem when I put my own 15 mm Canon fisheye lens on the 5D that there would certainly not be a vignetting problem when we're talking about a 16 mm minimum focal length. Doesn't something seem to be awry here? And why is it vignetting at the top but not the bottom?

first of all, fisheyes are a little different from regular lenses... wide-angles in general have more trouble with CA and vignetting than telephotos. dunno about vignetting at the top only. did you take a picture of just the sky or a blank wall or something? 'cause vignetting won't always be apparent in all the corners, if at all.

And I just looked, it is indeed the original version, not the II. And that sucks. I like my 17-40 f/4.0 a lot better and it's half the bloody price, but unfortunately I have to send it in to Canon for a repair.

yeah, the 16-35 II is lots better than the original, and better than the 17-40 as well.

 

[ChrisA]

Also worth noting, there was a UV Haze filter attached to the lens that I never removed when taking shots with it, but surely that wouldn't cause vignetting and chromatic aberration would it?

Vignetting, yes. That is likely. Unless it was a very thin filter designed for wide angle lenses. But this would not be the cause of any CA.

Chromatic aberration is something all lenses have. Some control it better but hey all have same

 

[joelypolly]

lens could have been dropped

The lens being a rental might not have been well looked after or dropped. A dropped lens could cause one of the elements to shift. Even a small shift will cause worse CA/image quality especially around edges.

You can't really tell just by looking at the lens and might have to send to Canon to confirm.

 

[gkarris]

Wow...

The lens being a rental might not have been well looked after or dropped. A dropped lens could cause one of the elements to shift. Even a small shift will cause worse CA/image quality especially around edges.

You can't really tell just by looking at the lens and might have to send to Canon to confirm.

That's what I was thinking. Bring a sample to the store with you and let them try it out on one of their cameras.

Someone might have dropped the lens and conveniently "forgot" to tell them.

Make sure you mention it to them as they might blame you if there's a problem.

 

[bobert83]

I have seen worse, but that is pretty bad.