topic Re: 100-400 4.5-5.6 troubleshooting, paper between lens layers? in EF & RF Lenses

100-400 4.5-5.6 troubleshooting, paper between lens layers?

John_Arneson — Thu, 29 Jun 2023 21:59:24 GMT

Anyone seen this before? Still seems to shoot fine even around what appears to be paper between the lens layers... unfortunately discovered on vacation/photo shoot 😉 Any idea how problematic it will be to repair ($-$$$)...

Re: 100-400 4.5-5.6 troubleshooting, paper between lens layers?

wq9nsc — Fri, 30 Jun 2023 00:49:33 GMT

Does that have a screw on filter with the debris caught between the filter and the lens glass?

Rodger

Re: 100-400 4.5-5.6 troubleshooting, paper between lens layers?

John_Arneson — Fri, 30 Jun 2023 01:08:07 GMT

I wish! 😉 Unfortunately it's between the internal glass layers.

Re: 100-400 4.5-5.6 troubleshooting, paper between lens layers?

shadowsports — Fri, 30 Jun 2023 06:06:47 GMT

Greetings ,

I'm on my phone right now so I can't get a good look. I do know that my 100-400 doesn't have any paper shavings. I'll look at it more closely in the morning.. Any idea how whatever it is got in there?

Re: 100-400 4.5-5.6 troubleshooting, paper between lens layers?

JFG — Fri, 30 Jun 2023 06:45:26 GMT

How long have you had that lens? If the piece is ingrained in the glass, then quality control had a blind inspector! Did it come like that new or did you purchase it used? It is hard to believe that could happen.

Re: 100-400 4.5-5.6 troubleshooting, paper between lens layers?

shadowsports — Fri, 30 Jun 2023 14:43:55 GMT

@JFG wrote:
How long have you had that lens? If the piece is ingrained in the glass, then quality control had a blind inspector! Did it come like that new or did you purchase it used? It is hard to believe that could happen.

Yes. All of this ?? We are going to need the back story on this. That is one of the most bizarre things I've seen.

Re: 100-400 4.5-5.6 troubleshooting, paper between lens layers?

ebiggs1 — Fri, 30 Jun 2023 14:57:56 GMT

It is a flaw for sure. The question now becomes what do you do? If it doesn't impact the photos perhaps you forget about. If on the other hand you want it fixed it will need to go to Canon. Now the question is, is it still under warranty or is the dime on you? Call Canon and set up a C&C.

Re: 100-400 4.5-5.6 troubleshooting, paper between lens layers?

amfoto1 — Fri, 30 Jun 2023 18:01:13 GMT

This appears to be "separation".

Some lens elements are "glued" together to form a "group". Sometimes the glue between them fails for one reason or another. It ends up looking a lot like this. If this is the case, AFAIK the only solution is to replace the group.

Another possibility is that some moisture got into the lens and dripped onto the surface of an element, leaving a "deposit" of minerals or whatever. Think of the water spots you see on glass when it's left to dry, for example. This might be more easily fixed... just a good cleaning, although disassembly of the lens would still be needed.

The thing to do is get it into Canon USA repair dept. and have them look at it. They can give you a repair estimate. I can't.

NOTE: If this is the earlier version of the lens, with the push/pull zoom, I recommend you call Canon first to be sure they still work on that version. It's been out of production for almost 10 years now. If it's the "II" version, should be no problem getting work done on it.

***********

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

Re: 100-400 4.5-5.6 troubleshooting, paper between lens layers?

normadel — Fri, 30 Jun 2023 19:39:18 GMT

This isn't a random mineral deposit. It is a chunk of something. Doesn't look like it could be adhesive from in between elements. Could a push-pull zoom have sucked in a big piece of something like this?

Re: 100-400 4.5-5.6 troubleshooting, paper between lens layers?

MikeSowsun — Fri, 30 Jun 2023 22:17:24 GMT

Canon actually uses pieces of black tape inside many of their lenses. My guess is a piece of tape has come loose and found it’s way to the front of the lens.

Re: 100-400 4.5-5.6 troubleshooting, paper between lens layers?

John_Arneson — Fri, 30 Jun 2023 23:26:49 GMT

Thanks for all the feedback! Mike the images you shared look similar, and the explanation makes sense 👌

This is the old IS version, bought it used 5 years ago for about 700 and it’s worked wonderfully. The autofocus is just not functioning properly now. Planning to send in to Canon for a repair estimate, if possible to just remove the tape they’ll likely give it a go. It’s not supported anymore so if other parts are needed I’ll likely have to move on.

Will post an update in a few weeks.

Re: 100-400 4.5-5.6 troubleshooting, paper between lens layers?

jrhoffman75 — Sat, 01 Jul 2023 12:10:17 GMT

@John_Arneson wrote:
Thanks for all the feedback! Mike the images you shared look similar, and the explanation makes sense 👌
This is the old IS version, bought it used 5 years ago for about 700 and it’s worked wonderfully. The autofocus is just not functioning properly now. Planning to send in to Canon for a repair estimate, if possible to just remove the tape they’ll likely give it a go. It’s not supported anymore so if other parts are needed I’ll likely have to move on.

Will post an update in a few weeks.

Please let us know what Canon says, including if they say they won't work on it at all. I have read elsewhere that once they run out of parts they won't work on a device because if they inadvertently damage something they won't be able to repair it.

Re: 100-400 4.5-5.6 troubleshooting, paper between lens layers?

shadowsports — Sat, 01 Jul 2023 15:06:31 GMT

+1 on that John. midwestcamera dot com is another alternative given the age of the lens.

Re: 100-400 4.5-5.6 troubleshooting, paper between lens layers?

ebiggs1 — Sat, 01 Jul 2023 18:39:55 GMT

"... I have read elsewhere that once they run out of parts they won't work on a device because if they inadvertently damage something they won't be able to repair it."

Its not just that which is probably a minor factor but Canon goes over the entire camera or lens before they return it. If there is any other part they don't have and they replace it they cannot guarantee the lens.

Re: 100-400 4.5-5.6 troubleshooting, paper between lens layers?

John_Arneson — Wed, 23 Aug 2023 16:34:39 GMT

Hey all, in followup it turns out it was the backing to the flex circuit and thankfully Mike at PhotoTronic in Topeka was able to fix and ship back under $200, top notch work 😃

Canon would not accept for return, offered a tiny discount on trade in for a newer model.