Problem with EF-S 10-22mm Image Softness

[ajperk]

Hello everyone,

This is my first time posting to the Canon Rumors forum, and I had an issue with a lens that I wanted to get some insight into and some advice on.

I purchased a refurbished EF-S 10-22mm wide angle lens a year or two ago from the Canon Refurbished store. I've been using the lens pretty regularly since I bought it. Recently I've noticed that the left side of pictures taken with the lens are really very soft, even stopped down (f 8 or 11 or so), and even when objects on the right sight of the picture (that are within the same plane) are sharper and in focus. I don't see the problem in earlier photos taken with the lens, and it does not require pixel-peeping to see the problem in the more recent pictures. I have never dropped the lens, and generally keep it stored in my camera bag, so if some sort of damage did occur I'm not sure what it would have been.

I know that wide angle lenses tend to lose resolution towards the edges and corners of the frame, but it is really the difference between the two sides of the images that leads me to believe it may be some sort of other problem.

Anyway, to get to the point, I was wondering: 1. What sort of defect or damage causes the sort of problem I'm describing? and 2. Has anyone sent a lens with a problem such as this to Canon and had it successfully repaired (and if so, do you recall about how much the repair cost)?

Thank you all for your help and advice!

 

[neuroanatomist]

Asymmetrical loss of sharpness is usually due to decentering of one (or more) lens elements. Canon can certainly correct the problem, not sure of the cost (depends on the severity), but figure $200 more or less.

 

[Mt Spokane Photography]

Asymmetrical loss of sharpness is usually due to decentering of one (or more) lens elements. Canon can certainly correct the problem, not sure of the cost (depends on the severity), but figure $200 more or less.

+1.
You can test for decentering. Use a flat brick wall, make certain you are setup absolutely perpendicular to it. Rotate the camera at 90 degree increments, taking images at each. It the soft area rotates with the image, send it to Canon with a description of the issue.
Decentering happens as a lens is used, there can be various internal causes, usually related to bumping the lens. Canon will replace any damaged parts, and realign things. The cost may vary depending on the parts and labor required.
When buying a used lens, its a good idea to check for decentering since its so common.

 

[ajperk]

Thank you guys for your help and advice. I'm going to call Canon and get the lens sent out for repair.

Take care!

 

[fear_through_the_eyes]

I bought this lens brand new about two years ago, and soft corners have persisted ever since. Stopping down doesn't seem to help at all. So I don't think yours has any real hardware issues. Most probably just a general character of this lens.

 

[dmills]

I bought this lens brand new about two years ago, and soft corners have persisted ever since. Stopping down doesn't seem to help at all. So I don't think yours has any real hardware issues. Most probably just a general character of this lens.

Softness on one side is definitely not a characteristic of this lens, but a decentering issue, as Neuro mentioned. I personally find my 10-22 on a crop sensor to be MUCH sharper in the corners than every 16-35L I've used on a full frame...

 

[BrandonKing96]

Hopefully Canon fixes it for you at a decent price. I've used mine for over a year now and I've had no issues with sharpness. But I seldom use the 10-22 now that I bought a 24-70 II (yes, I know they're different ranges but the 24-70 is now my walk around)

 

[ajperk]

So, I sent the lens into Canon, and they said there would be no cost for the repair, as it was covered by the warranty. I had purchased it refurbished and I had thought that refurbished lenses only had 90 day warranties. It was purchased in March, so we're definitely outside of the warranty coverage at least as I understood it.

Nevertheless, I didn't argue with them and after about a week and a half at their repair facility, they are now sending the lens back to me. Hopefully it's fixed up and all is well.

Thank you all again for your replies!