Bad contact between lens and camera- ERROR 01

I own a Sigma 400mm f5.6 APO Tele Macro HSM. It is a not chipped model, so I can only use it wide open with my 450D.

When temperature gets colder than 10 degrees celcius, I get an error 01 on my 450D. When I press the lens hard to the camera mount, I don't get an error anymore. If I let it warm up again, it works fine too.

I think the problem is a bad contact between the lenscontacts and the camera contacts. I already tried cleaning it with 90% alcohol, but this didn't help. Any other tips?

I had a similar problem with brand new Tamron 70-300VC that I just shipped back to vendor.
When discussing problem with them, they suggested tightening the screws around lens mount bayonet on both the lens and the body. Didn't work for me, but see if it works for you.

Try an pencil eraser, I had a problem a while back with contacts between the camera and lens, and also just the other day with the contacts on my hotshoe. Canon suggested an eraser. Dont rub hard, but just enough to clean. alcohol will clean but wont remove any surface corrosion
Worked on Mine

I don't know what you mean by "not a chipped model".... If it's an AF lens, has electronic contacts, and since it's an HSM lens it most certainly is... Then it's got a controller chip in it to operate the AF and the aperture. As such, there is no reason you shouldn't be able to stop it down on your camera.

You did the right thing cleaning the contacts.... usually that clears up lens to camera communication problems.

No, don't use a pencil eraser on lens-to-camera electronic contacts. The most recent white paper from Canon about clearing error codes specifically recommends against it, though I know their techs have suggested it in the past. Now they are saying to not use an eraser because it risks damaging the gold plating on the contacts. However, the reasons I think it's a bad idea to use pencil erasers are that often the problem with contacts involve oils... and pencil erasers are made from vegetable oil, so will do little or nothing to help remove any oily coating on the surfaces, might even make matters worse. Also, erasers shed particles that are risky because they might get into camera mechanisms.

The reason to use an eraser carefully on some other types of electronic contacts is to remove corrosion. That's fine on chrome plated, stainless steel, etc., contacts that can become corroded. However gold plated contacts cannot corrode (gold is entirely non-corrosive, which is precisely why they go to the trouble and expense to use it on the lens-to-camera contacts).

If tightening the screws doesn't work, I'd be contacting Sigma about sending it in and getting it fixed.

amfoto1 wrote in post #13943585
I don't know what you mean by "not a chipped model".... If it's an AF lens, has electronic contacts, and since it's an HSM lens it most certainly is... it's got a controller chip in it to operate the AF and the aperture. As such, there is no reason you shouldn't be able to stop it down on your camera.

You did the right thing cleaning the contacts.... usually that clears up lens to camera communicatioin problems.

If tightening the screws doesn't work, I'd be talking to Sigma about getting it fixed.

The lens is over 10 years old and Sigma doesn't service these lenses anymore. Due to Sigma's back engineering they don't work 100% on new camera's. The aperture cannot be controlled anymore and the lens only works wide open. But this is not the problem, since I have a few friends with the same lens. They don't have the problem I have.

[QUOTE=amfoto1;1394358​5]to camera communication problems.

No, don't use a pencil eraser on lens-to-camera electronic contacts. The most recent white paper from Canon about clearing error codes specifically recommends against it, though I know their techs have suggested it in the past. Now they are saying to not use an eraser because it risks damaging the gold plating on the contacts.

Could you please provide a link to this white paper. Id like to read it.
Thanks

I recently read that paper, but can't find it now. Just found it == here it is (page 2 has what you want to read)

Warning: do not clean lens contacts on either a Canon lens or the camera body with an eraser! It’s incredibly easy to rub off the gold plating on these contacts, and end up with data communication problems, even if that wasn’t the original source of the problem!


http://www.learn.usa.c​anon.com …2012/eos_error_​msgs.shtml

Thanks Rick,
I see it was written this month. I sure hope the customer service at Canon has been informed. This was in December when I was in contact with them. I also questioned the method he was giving me as something not to do, but was reassured It was OK.
Sorry for the missinformation I just passed along. Seems its not the best idea or method to use.
Also thanks amfoto 1 for bringing this to light.

Fred,

I've used erasers, I think we all did. I've seen something else more detailed on why not to use them, but I can't locate it. It describes in some detail what pencil erasers are made from and why not to use them on gold plated contacts. If I dig it up, I'll post it too.

Just got that message for my Canon 24-105mm last night. On either camera.

The camera shop said to try an eraser, which I did, and the problem persists. They suggested sending the lens to Canon if the eraser didn't do the job.

I'm curious about this. I just bought a 35mm f2 off this site's FSOT section and encountered it three times this afternoon. I've never had this problem with my 2.5 year old t2i before. Not sure what to do. I cleaned the contacts with a microfiber cloth tonight but now don't know if I can trust the lens.