topic Re: The Curious Case of the EF 28-300L IS USM... in EF & RF Lenses

The Curious Case of the EF 28-300L IS USM...

Tronhard — Mon, 27 Jun 2022 05:01:25 GMT

I have the venerable, and unique Canon EF 28-300L IS USM super-zoom lens. It seems to be in perfect condition and has been so for some time since I bought it about 10 years ago. Recently, when I began shooting with it using my FF cameras: EOS 5DMkIII, MkIV, 5DsR, and in each case it takes one or two images and displays the dreaded 01 error: Cannot communicate with the lens, clean contact. Because the lens displays the same issue on several cameras, it is logical to assume that the lens has a fault.

So that is what I have done (several times) is clean the sensors on both camera and bodies: they don't seem particularly worn and are bright and shiny.

HOWEVER! If I put the lens on my crop sensor cameras: 60D, 7DI, 7DII, 80D, 90D, M5 (with adapter), and the FF R5 (with adapter) it performs perfectly, working through the various zoom and shutter speed ranges and at high speed continuous shots.

That, I find somewhat confusing. I looked at the contacts and compared them to other lenses, and there are exactly the same number of contacts and in similar condition, yet they work fine!

I am throwing this out there to the brains trust and any Sherlock Holmes!!!

Re: The Curious Case of the EF 28-300L IS USM...

AtticusLake — Mon, 27 Jun 2022 07:01:52 GMT

I have no knowledge of that lens, or even the EF system particularly... so take this with a grain of salt. However, I have worked on tech devices for 40 years or so.

When you are communicating with some device -- such as the computer inside the lens -- you can detect that something has gone wrong. In that case, you try to guide the user to fix it themselves by suggesting the most likely cause. In this case, that would be dirty contacts. In other words, "dirty contacts" isn't an actual diagnosed problem, it's just the suggestion that's most likely to be of use to a typical user. I.e. a guess.

In your case, it looks to me like something has gone wrong inside the lens -- maybe a bad solder joint. Thermal cycling over years, slight vibration, etc., might have just got it to the point where it's come loose.

As for why it works on crop cameras -- yes, the contacts are the same, but they might be used differently on those cameras. Maybe some contacts aren't used at all. I dunno, like I said I don't know EF. But I can basically guarantee that what's going on behind the scenes is more complicated than you would think -- because it always is.

Anyhow, sadly, I think your lens needs repair. Best of luck, and I hope this has provided some illumination.

Re: The Curious Case of the EF 28-300L IS USM...

Tronhard — Mon, 27 Jun 2022 08:29:10 GMT

Thanks for your input, Atticus. What puzzles me is that it works with the R-bodies via the adapter. It even works with the FF EF bodies, but only for a few shots, and then it gives the error message, so there is a circuit connection. Logically one would expect that those RF cameras would use the same circuits as the EF units, but in that case they show no errors.

Absolutely, sending it in might be an idea, but I suspect that the lens will not be serviced as it is a vintage 2004 unit. Well past the normal servicing envelope.

That said, it works perfectly with the various crop bodies: EF-S and EF-M alike and with the RF mount, so even if I can't get it serviced, I can still use it and the good news is that it works with the newest tech. I don't use this lens a lot, so it's not mission critical but it is a challenge...

Re: The Curious Case of the EF 28-300L IS USM...

ebiggs1 — Mon, 27 Jun 2022 15:35:59 GMT

Trevor it looks like once again you have proved my standing that cleaning the contacts on either lens or camera does very little to nothing.

Re: The Curious Case of the EF 28-300L IS USM...

ebiggs1 — Mon, 27 Jun 2022 15:39:06 GMT

"But I can basically guarantee that what's going on behind the scenes is more complicated than you would think -- because it always is."

I would have to disagree with that. Not always anyhow. Plus it is always, always, best to eliminate the simple or easy things first.

Re: The Curious Case of the EF 28-300L IS USM...

AtticusLake — Mon, 27 Jun 2022 15:47:03 GMT

Well, I'm afraid I have to disagree with your disagreement. After a lifetime spent developing tech products (phones, tablets, netbooks, etc.) I can absolutely tell you that products like that are always more complicated than an outside user would think.

Of course it's always sensible to eliminate the simple options first. I certainly would have started by cleaning the contacts (if they looked dirty). But if you start wondering about why something happens in one situation but not another, just know that the internals of these devices can be way more insane than you might imagine. You might think, for example, that the EF communications protocol is one, simple protocol; but given all the changes that have happened over the years, I would bet that it isn't. I wouldn't be surprised at all if a lens used completely different communications methods depending on what camera it's attached to. Like, for example, SD cards do.

Re: The Curious Case of the EF 28-300L IS USM...

ebiggs1 — Mon, 27 Jun 2022 15:49:40 GMT

Sorry to not be of any help. Actually I had one of them a long time ago. I didn't keep it long. I'll keep my opinion about it to myself for now. Actually I did not know it was still in production or available. It does need to go to Canon for service.

Re: The Curious Case of the EF 28-300L IS USM...

ebiggs1 — Mon, 27 Jun 2022 16:01:39 GMT

"Of course it's always sensible to eliminate the simple options first."

What's the point if it is always the most difficult complicated thing . You may as well skip the easy stuff if it can't be that simple. In reality it can be that simple and often times it is a simple thing. And guess what Canon service will know.

Re: The Curious Case of the EF 28-300L IS USM...

kvbarkley — Mon, 27 Jun 2022 16:06:53 GMT

I am going to take a WAG and assume it has something to do with signal level and buffering. When connected directly to the camera the lens does not have enough oomph to drive the interface. The adapter has a buffer and does not load down the lens as much so that it amplifies the signal as it goes through.

Re: The Curious Case of the EF 28-300L IS USM...

AtticusLake — Mon, 27 Jun 2022 16:20:48 GMT

I think you misunderstood my post. I'm saying that technology products are always more complex than they seem. This was in response to Trevor wondering why his issue happens on some cameras and not others.

I'm not saying that any given problem is "always the most difficult complicated thing". In fact it almost certainly isn't. It's often going to be something pretty simple. And the most difficult complicated thing is pretty horrific.

Re: The Curious Case of the EF 28-300L IS USM...

Waddizzle — Mon, 27 Jun 2022 16:51:14 GMT

Here’s my two cents. Your observations are consistent with a possible firmware issue. It works with APS-C bodies of various vintages but not with some full frame bodies that are more recently released

Re: The Curious Case of the EF 28-300L IS USM...

ebiggs1 — Mon, 27 Jun 2022 17:04:54 GMT

"Your observations are consistent with a possible firmware issue."

I like that thought. Still requires a trip to Canon service.

Re: The Curious Case of the EF 28-300L IS USM...

ebiggs1 — Mon, 27 Jun 2022 17:07:32 GMT

"I'm not saying that any given problem is "always the most difficult complicated thing""

You need to be more clear then.

" In fact it almost certainly isn't."

My point! 🙂

Re: The Curious Case of the EF 28-300L IS USM...

Waddizzle — Mon, 27 Jun 2022 18:37:47 GMT

It may only require camera firmware updates.

Re: The Curious Case of the EF 28-300L IS USM...

Tronhard — Mon, 27 Jun 2022 18:46:13 GMT

Thanks Bill, but I tried looking for a firmware update when this started and there is none available for this lens, and my cameras are all up to date with their firmware according to the sites. Good try though! 🙂

Re: The Curious Case of the EF 28-300L IS USM...

Tronhard — Mon, 27 Jun 2022 19:36:33 GMT

Hi Ernie and thanks for you input. 🙂 This lens is part of my "legacy" collection and not used for my day-to-day photography, but I like to use this gear from time to time for the enjoyment and to make sure it works - obviously, I have found an issue.
I think the next step, as you say, is to consider sending it to Canon: if they will even take a look at it... The thing is, that even if they refuse, I can still use it on my crop bodies and my new gear, so it's not like I can't use it at all - it's more of a slightly annoying itch I want to scratch!

Re: The Curious Case of the EF 28-300L IS USM...

ebiggs1 — Tue, 28 Jun 2022 14:21:47 GMT

"It may only require camera firmware updates."

Oh yeah, right, now I don't like the idea so much.

Re: The Curious Case of the EF 28-300L IS USM...

ebiggs1 — Tue, 28 Jun 2022 14:24:57 GMT

"I think the next step, as you say, is to consider sending it to Canon: if they will even take a look at it... "

It' still for sale on the market, isn't it? I would assume Canon has to still service it.

Re: The Curious Case of the EF 28-300L IS USM...

Tronhard — Tue, 28 Jun 2022 20:15:00 GMT

Canon NZ is not as forthcoming as the US version. I asked them and they simply said that they would look at it but would not commit to fixing it, rather disappointing I thought. They said it could be dirty contacts (already cleaned) or anything, which is rather vague. I will likely send it in to them for evaluation, but if they refuse to service it, at least I know it works with a lot of cameras!

Re: The Curious Case of the EF 28-300L IS USM...

Tronhard — Mon, 04 Jul 2022 21:33:44 GMT

Well, a footnote to this post. Initially, when I contacted the Canon NZ service desk they said to bring it in for an evaluation. Then they declined to do so. It turns out that while the Australian branch sells and supports the 28-300 currently, NZ does not - which is odd considering the warranties issued for gear sold in this region apply to Oz and NZ. So, I shall stick with using the lens of APS-C and via the adapter on my R5 and R6 units. Not impressed with Canon NZ though...