17-40L SCRATCH!

It seems I somehow got a small scratch on the front element of my 17-40L. I am not sure how this happened but if I had to guess I would say the time I pulled it out of the bag and noticed the front lens cap had fallen off. I was wondering, is this something I can send to canon to have fixed? Would it be worth it money wise?

Thanks

You should first check if it even shows up in your photos. Shoot various things that provide rich colors. Shoot wide open and stopped down. See if anything even shows up.

I doubt it will even show up. I wouldn't worry to much, but than again it really depends on how deep and long this scratch is. do what grego said, then make your decision.

ouch - sorry to hear about this...but i sure would put a filter on a premium lens like this!!! i can't wait to get mine! lens that is...not the scratch!

I bet ya this is one point against the no filter(only hood) campaign

The probability is high that is really is not a scratch, but a deposit left by something that got wiped across the lens.

Look at the "scratch" with a fairly high power magnifying glass or a loupe (10X or more)and see if it really has depth to it or whether it is something deposited on the lens.

Many folks have cleaned "scratches" off their lens with appropriate cleaning solutions. Sometimes they have needed to try a few different cleaning solutions, but cleaning was the answer.

If if is truly a small scratch, it probably will have no effect on your images. If you put a 1/4-inch diameter opaque sticker on the lens you will not be able to see it in an image.

Except when you are shooting in backlit conditions it is possible to get a reflection off the scratch.

Canon can easily change the front element. Probably not cheap though.

It might be cheaper to E-Bay it and get a new one, rather than getting it fixed.

Sory to hear this - that's why I put a filter on all my lenses. Even a hood wouldn't have stopped that accident.

On the bright side, most likley the scratch won't affect the image. You can always have it repaired - they just replace the front glass.

Another option is if you have insurance, it might be worth claiming. check what a claim will do to your next premium though.

savone wrote in post #2109926
It seems I somehow got a small scratch on the front element of my 17-40L. I am not sure how this happened but if I had to guess I would say the time I pulled it out of the bag and noticed the front lens cap had fallen off. I was wondering, is this something I can send to canon to have fixed? Would it be worth it money wise?

Thanks

It probably will not show up except perhaps under strong lighting conditions.

First check by shooting a plain even surface at minimum focal length and a small fstop, say f16 or f22 acuratly focus on the target surface as close to the minimum focus distance as you can.

I doubt anything will show but this should be worst case for the scratch showing in the image even faintly.

Secondly shoot with a bright light source in the frame and a dark background, you might want to try this in the street at night or by setting a lamp setup in a room at night. Expose so the general background is about a stop under exposed at various focal lengths and fstops.

This will check for flare and general loss of contrast which is the mostly likely symptom of damaged coatings. If you can, compare with a known good lens under the same conditions.

The front element on L glass is not part of the optics, its a protective element IIRC.

jcw122 wrote in post #2110533
The front element on L glass is not part of the optics, its a protective element IIRC.

you're talking about some of the long lenses, not the 17-40.

ed rader

Thanks for all the info guys, I will run some tests sat morning when I get a chance. As far as keeping filters on the lens, wouldnt that be counter-productive? I mean wouldnt a $60 filter degrade the optics at all? As far as keeping the hood on, that just isnt practical when carrying 4 lenses, body, and various other goods in the bag.

Thanks again!

Sorry to hear that, I know if it was me that would drive me nuts, even if it didnt show in the shots things like that really annoy me.

Without sounding like "I told you so" this is the reason why we use UV/protection filters, some say a lens hood is good enough but I dont believe that for one second, the hood is only good for what its designed for, stopping light entering the lens & while the coatings on a lens front element are tough, it shows they are not that tough!

Nick

savone wrote in post #2110720
Thanks for all the info guys, I will run some tests sat morning when I get a chance. As far as keeping filters on the lens, wouldnt that be counter-productive? I mean wouldnt a $60 filter degrade the optics at all? As far as keeping the hood on, that just isnt practical when carrying 4 lenses, body, and various other goods in the bag.

Thanks again!

Buy a UV & try it, lots of us have run tests & find no image degradation at all, sharpness is identical with or without a UV, the ONLY time a UV can cause a problem is if your pointing almost up at the sun, lens flare can be quite bad then, but it would still be pretty bad without a UV in those situations.

I wouldnt get THE cheapest, but you dont need the most expensive either, I use a Hoya G Series which is the cheapest coated UV Hoya make & I leave it on all the time, ive never had any problems.

Nick

Nick_C wrote in post #2110740
Sorry to hear that, I know if it was me that would drive me nuts, even if it didnt show in the shots things like that really annoy me.

Without sounding like "I told you so" this is the reason why we use UV/protection filters, some say a lens hood is good enough but I dont believe that for one second, the hood is only good for what its designed for, stopping light entering the lens & while the coatings on a lens front element are tough, it shows they are not that tough!

Nick

and some say only use a protective filter when there is a high likelihood of accident, and we all know that accidents happen when we most expect them !

ed rader