Advice please regarding 24-105 F4 L Lens

When I purchased my 5D Mark III it came with a 24-105 F4 L kit lens. The lens is now out of warranty although it has been used very little. As I was taking pictures of the lens to post a "for sale" ad on this forum I noticed a small blemish on the mount end of the lens. I have been please with the pictures from the lens. However, I recently purchased a 24-70 F2.8 II. Since acquiring this new lens, I have not used the 24-105.

I question now if I should attempt to sell the lens with this small blemish. As I mentioned I have been pleased with the pictures and did not know this blemish was there until taking the pictures. I have attached a picture to give you an idea of what I am seeing.

I may need to just contact Canon. I was thinking I would sell this lens and invest the money in another 600EX-RT or some other new lens. However, I do not want to try to sell it if this is considered to be a major flaw, or flawed to the point that no one would want to buy it. To me it is not a flaw at all, however, it is noticeable when holding the lens at the right angle.

Please let me know what you think. I want to be fair about it.

Thanks much for any input.

The spot to which I am referring is on the top right hand corner of the glass. It almost appears as if the coating on the inside of the glass has come off.

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Heya,

The kit lens goes for a lower price due to it's high volume on the market. It's an excellent lens. It's not super duper. But it's great. That said, you'll see it for $600 commonly. If the blemish you have is not showing up at all on photos (test it, do some photos of a single color card, or gradient card or something like that), then it really doesn't matter. If you're not using it, it's not going to do anything for you other than collect dust and be a paper weight. Just be transparent about the blemish when selling it and show an image that it doesn't affect or do anything to images or quality, and sell it for like $550. That's a great price, I'd buy it for that even, and put that money towards your next lens for your GAS.

Very best,

Thanks MalVeauX,

Sounds like a good plan. I will pick up some colored and gradient paper...take a few shots just to be sure. That should be a pretty good way to test it. Thanks again for responding!!!!

That seems like a really strange blemish, almost just an internal reflection. Have you tried wiping it with a water-wet cloth? I've seen a number of time people have had stuff on the glass that they can't easily just wipe of - even sometimes with lens cleaning fluid.

I've seen marks like that on rear elements before, usually just a spot from a droplet of something hitting the rear of the lens. I'd try cleaning it as mentioned before writing it off as a real blemish.

The shroud at the back end of the 24-105 does protect the element; I think you'd have to do something quite imaginative to damage the coating.

Like the others, I'm inclined towards trying isopropyl alcohol and a clean lens cloth. You might be pleasantly surprised.

WOW.....xhack, Colorblinded, ejenner....I cannot thank you enough. I used isopropyl alcohol and a clean lens cloth and it came right off on the first pass. I should have thought of trying this, but I guess I was so shocked over the whole thing. I take exceptional care of all of my gear. I looked at the spot a hundred times and it truly looked like the coating was coming off.

Anyway....again I cannot thank you enough. Thanks to you.....it was such an easy fix....not a blemish at all. Thanks you!!!!!!

Glad you got it taken care of. I remember when I got my 24-105 I had something on the front glass that wouldn't come off with my usual cleaner. I though I damaged the glass within the first week I had it. Then I got my Zeiss wipes and wow, the mark came right off.

Good luck selling the lens.

Glad it worked out. I've had those spots when changing lenses in a Scottish smirr (a heavy mist that's nearly, but not quite rain). Water marks can look worse than they are.