Canon 28-70mm f/2 smudge issue

[fahadyunus]

Dear Canon Support Community,

I am writing to seek urgent assistance regarding an issue I have encountered with my Canon 28-70mm f/2 lens. In August of 2021, I noticed the presence of small smudge prints on the front element of the lens. It is important to note that the lens was in perfect condition the previous night, and I discovered the smudge prints when I woke up for a shoot. The smudges did not initially affect the images captured. However, this lens is crucial to my work as it serves as my primary lens for all my wedding shoots and personal projects.

Concerned about the smudges, I promptly took the lens to the Canon India Service center. Unfortunately, they immediately blamed me for scratching the lens surface, even though the lens was still under warranty at the time. Despite my insistence, they refused to accept the lens for further inspection to determine the cause of the issue. Their suggestion was to continue using the lens as it was not visibly affecting the images.

Now, fast forward to the present, the smudges on the lens have significantly increased in size and quantity. As a result, the quality of the images captured is visibly affected. I have attached pictures for your reference.

To my dismay, I have discovered that I am not the only person facing this issue. A quick search on various forums, including Reddit, reveals that at least five other individuals have experienced the exact same problem with the Canon 28-70mm f/2 lens. What is even more concerning is that none of the Canon Service team members have provided a definitive cause for this issue.

As a professional photographer and a loyal Canon customer for over a decade, I believe it is crucial to understand the root cause of the problem in order to prevent future occurrences and maintain trust in Canon's products and services. Has anyone in the community faced this issue? August 2021June 2023

[ebiggs1]

"...  the front element was exposed to some acidic or corrosive  ..."  or impact of some kind.

I am agreeing with that. Something contacted the front of the lens. Who knows how you used this lens or where and under what conditions. We certainly don't. It is another good example for the use a clear protecto filter on expensive lenses. But that is closing the gate after the horse has fled!

[ata]

The fluorine coating on the windshield of the lens is damaged. And over time (in my opinion, fluorine is an external factor that causes the surface to deteriorate.) This situation spread over the surface of my soul..

Fluorine coating powder, water, etc. It prevents external factors from sticking to the surface. The user can guess what caused the coating to fail.

[ebiggs1]

"This situation spread over the surface of my soul.."   WOW! 😮

[Peter]

 I don't use protection filters, but if I ever get RF28-70 or EF 24-70/2.8 II USM I will due to the optical coating issues I have seen.

[fahadyunus]

I had used it for a year like that until it started affecting my pictures. I had the front element replaced just last week. 

[Anonymous]

It's good to hear that you got it taken care of. I would put a clear filter on it to prevent a reoccurrence of the problem.

[amfoto1]

I'm glad to hear Canon is working with you on this and the problem resolved.

But, without close inspection, I can't be certain if those flaws are on the outer surface of the lens or if they are inside. All the above discussion assumed it was on the outer surface. However, looking at the images it also could be internal... and that suggests other possibilities:

- Coating failures (much like on external surface)

- Separation... failed adhesive between two elements in the front group.

- Fungus.

I'm kind of leaning toward the latter, since it appeared to be "growing".

***********

Alan Myers
San Jose, Calif., USA
"Walk softly and carry a big lens."
GEAR: 5DII, 7DII (x2), 7D(x2), EOS M5, some other cameras, various lenses & accessories
FLICKR

[Danfaz]

I just watched an Irene Rudnyk video where she's in Bali, shooting with the 28-70 (appears to be sans filter) at a waterfall. Wonder if she'll have this issue?

[Farrah_Nichole]

Hi! I know this is a few months old but I came across the thread after doing some research in other photography groups/forums on Facebook. This IS an issue with MANY of their 28-70 f2 copies. It is NOT user error. I have also attached mine which is doing the same. I have contacted Canon, hoping they can provide me a solution! Has anyone else gotten any help from Canon support?

[fahadyunus]

Hi Farah. I got my lens serviced at Canon and paid for the front element to be replaced. After that episode, a friend of mine who has the same lens faced the exact same issue. I now feel that I should have fought Canon instead of paying for the service which was quite a heavy amount. 😞 Please let us know what Canon service says. This issue is widespread and they need to take some responsibility instead of blaming it on the users.