Replacing front element on 24-70L II...........

over the last three years of fairly heavy use in all conditions I managed to get a couple of light scratches on the front element of my 24-70L II but what really prompted me to send the lens in for service was marks all over the front element I thought could possibly be fungus. it was not fungus but wear through the coating and I mean a lot of it. I do use a UV filter most of the time but for night photography and twilight stuff I use NDs or no filters at all. I've had to clean the front element a few times and sometimes not delicately while in the field so maybe a foreign object got lodged on the rag or my tee shirt or whatever I happened to use.

none of my other lenses are scratched or have coating wear.

anyhow I've decided not to use canon service any longer for non-warranty work because of their poor communication and sometimes steep charges.

the cost to replace the front element and the tattered rubber gasket is $468 shipped. This also includes cleaning and calibrating and a six-month warranty on work.

meanwhile I bought a new 24-70L II for an authorized dealer for $1639. after i sell the repaired lens to my buddy for $1200 (its his birthday) i'll pocket a little change and i'll also have a new lens with a one-year warranty, and also a 13-months no fault repair or replace policy for the merchant.

sure glad it wasn't fungus

I'd be interested to see comparison shots between new & old lens....

so far I don't see any difference but I'm not a pixel peeper nor have I ever micro adjusted any lens. with the new canon L lenses I feel confident shooting at any length or aperture. I think canon glass is the best right now and lenses like the 24-70L II and 16-35L f4 IS (just to name two) are the best zooms ever made by anyone. great time to be a photographer. oh I did ask them to send me the old element. I will be curious to give it a close look.

Just curious, you mentioned that you weren't going to use Canon for out of warranty repairs, but you said how much it was going to cost to fix. Is that one last time through Canon, or did you find someone else to do the repair?

the price was through an independent repair service -- Royal Camera Service. you send the lens in and get an estimate just like you do with Canon except with this company you can actually talk to someone on the phone and they answer your emails quickly. these guys deal in much smaller volume and they use only canon parts. with canon I was never sure what they did and sometimes if they did anything at all.

for my cars I only use the dealership for warranty work. never for service or repairs anymore. this is the same type of thing.

Good to know. Thanks.

It would be very rare to see any changes at all from marks in the coatings of the outer lens selement. The most that might happen is a bit more flare or contrast changes with sunlight directly hitting the front element at an incident angle, but even then it would be difficult to see anything between the two.

You could put a small 1mm x 1mm postit square dead center on your lens and take a shot, and not see it in your photo.

Only those with a bit of OCD would really be concerned with marks on the front element, of this I know as I belong in that camp. But after running tests with things stuck to the front of the lens, my OCD has abated a bit.

and yet 50% of the guys here swear protective filters degrade IQ. how do we explain that . I upgrade heavily used equipment periodically, especially when it's a lens that will be a mainstay of my kit for years to come. there are also a couple of slight scratches on the front element too and I occasionally see an odd diagonal flaring from this lens. anyhow it's a done deal now.

When I was looking for used copies of the 24-70 vII about a year ago, I saw something on the Lens Authority site saying that the coatings on the front element of this lens can get scratched very easily. Guess they must use a softer coating than they do with other lenses. Mine has gotten a couple of scratches near the outer edges, but still seems prime sharp at f/2.8 so I don't really worry about it. I love that lens!

A mark on the factory lens element does much less damage than an entire pane of glass in front of the same lens, especially one that is very poorly polished, or has imperfections in the glass. You can have a scratch on your cornea and see just fine, but put a bad contact lens on and you cannot see.

Might want to take a look at this:

http://kurtmunger.com/​dirty_lens_articleid35​.html

Lens flare, depending on obvious variables, may still be an issue but this guy puts a lens through hell & still gets better-than-expected results

I love it too and I think it'll be a relevant lens for at least five more years and probably longer that's one reason I didn't have any issues getting it serviced.. the coating was so messed up on mine that I thought it might be fungus, and that's why I sent it in. the front element is massive. it's at least 3/4" thick in the middle and weighs 185g. maybe i'll sell it on ebay or maybe i'll wear it around my neck on a gold chain. L bling lol

I get it dude, but thanks

look at how long I've been here. I've seen that article and many others like it over the years. post that on the next anti-filter rant would you

bogeypro wrote in post #17871940
Might want to take a look at this:

http://kurtmunger.com/​dirty_lens_articleid35​.html

Lens flare, depending on obvious variables, may still be an issue but this guy puts a lens through hell & still gets better-than-expected results

haven't done anything as extreme as him of course, but fyi, i saw he addressed smudges in his article and declared them not a big deal, but in my experience smudges REALLY matter. i've had a few good photos ruined because of smudges. dust, yeah, not so much. my recommendation: if you see a smudge, you definitely want to clean that.