Compatability of a film lens for a DSLR

[4hooligans]

I stumbled across a pretty good deal on my local FB for sale page. A lady was selling a film canon with an EF 35-70 macro lens and a Sigma AF 400mm 5.6 lens for $100. I scooped it up hoping the 400 would be compatible with my Canon 40D. The lens fits on my 40D, runs on, focus, and takes pic but about every tenth pic it will give me an error message say the lens and the body are not communicating, please clean contacts. Can anyone give me any insight? I did do some reseach and it appears at one point you could buy an adapter, but from what I have read that is no longer an option.

 

[amolitor]

Did you clean the contacts? I am pretty sure this combination should work fine, and the camera appears to agree with me.

 

[4hooligans]

Yes, I did clean the contacts, but with just a soft cloth, should I use something else?

 

[Dao]

Would it be the old Sigma lens need to be rechip?

 

[KmH]

In 1987 Canon introduced the EOS system, EOS is not compatible with the FD-mount, hence the need for an adapter to use FD lenses on EF camera bodies.

The late 1980's is when they started adding auto focus in most SLR cameras. Pentax and Nikon were the only 2 major camera makers that did not redesign their lens mount to accommodate AF.
Canon EOS - Wikipedia, the free encyclopedia
Canon EF lens mount - Wikipedia, the free encyclopedia
Canon EF-S lens mount - Wikipedia, the free encyclopedia
Canon FD lens mount - Wikipedia, the free encyclopedia
Canon FL lens mount - Wikipedia, the free encyclopedia

 

[4hooligans]

If it needed to be re-chipped, I am confused as to why it works at all???

 

[amolitor]

Pencil eraser is the usual standard issue contact cleaning device. Be sure to clean up any bits of eraser, though, thoroughly.

You might also have a damaged lens that simply isn't maintaining good contact, which would be a bummer.

 

[Buckster]

In 1987 Canon introduced the EOS system, EOS is not compatible with the FD-mount, hence the need for an adapter to use FD lenses on EF camera bodies.

The late 1980's is when they started adding auto focus in most SLR cameras. Pentax and Nikon were the only 2 major camera makers that did not redesign their lens mount to accommodate AF.
Canon EOS - Wikipedia, the free encyclopedia
Canon EF lens mount - Wikipedia, the free encyclopedia
Canon EF-S lens mount - Wikipedia, the free encyclopedia
Canon FD lens mount - Wikipedia, the free encyclopedia
Canon FL lens mount - Wikipedia, the free encyclopedia

Thank you Keith, for that very interesting Canon history lesson. However:

The lens fits on my 40D, runs on, focus, and takes pic

Thus, it's not the Canon mount change from FD to EF that's at issue here.

but about every tenth pic it will give me an error message say the lens and the body are not communicating, please clean contacts. Can anyone give me any insight? I did do some reseach and it appears at one point you could buy an adapter, but from what I have read that is no longer an option.

The adapter is not the resolution to the problem you're having. The adapter was made to accommodate Canon's old FD lens mount lenses to the new EF mount bodies. The FD mounts on the old lenses simply will not fit the new EF mounts on modern bodies without it. Yours fits, so it's not that.

Just F.Y.I. though, it's true that the originally made Canon adapters are very hard to come by, and are very expensive when they do come up for sale. Nonetheless, after-market adapters are readily available, in both chipped and non-chipped versions. I have one of each, and have used them to couple my Canon 500mm f/4.5 FD mount lens to my EF mount camera bodies.

As for contact cleaning, I've used pencil erasers with good success. For tougher grime, a bit of isopropyl alcohol can work, but try to get the most pure alcohol you can, free of scents and so forth.

For either, just be careful that you don't get excess into the camera body or lens. Use the eraser with the contacts facing down towards the floor so that any bits of eraser fall away from the body or lens, and inspect that they're free of any of that stuff before returning it to the upright position where they could potentially fall into the device. A twisting motion with the pencil works well on small contacts.

With alcohol or other cleaning solutions, don't over-saturate it. Use a Q-tip or, better yet, a lint-free cleaning swab. As with the eraser, it's best to work it with the contacts facing the floor so that nothing can drip or fall into the device you're working on. Look for and remove any fibers or other detritus after cleaning, and remove it.

If a good cleaning of the contacts doesn't solve the problem, it could very well be a problem with the electronics or even the mechanical components inside the lens, which would likely be much more difficult and costly to resolve, unless you're very good with disassembling, cleaning, repairing and reassembling somewhat delicate and precise instruments, such as lenses tend to be.

 

[4hooligans]

In 1987 Canon introduced the EOS system, EOS is not compatible with the FD-mount, hence the need for an adapter to use FD lenses on EF camera bodies.

The late 1980's is when they started adding auto focus in most SLR cameras. Pentax and Nikon were the only 2 major camera makers that did not redesign their lens mount to accommodate AF.
Canon EOS - Wikipedia, the free encyclopedia
Canon EF lens mount - Wikipedia, the free encyclopedia
Canon EF-S lens mount - Wikipedia, the free encyclopedia
Canon FD lens mount - Wikipedia, the free encyclopedia
Canon FL lens mount - Wikipedia, the free encyclopedia

Thank you Keith, for that very interesting Canon history lesson. However:

The lens fits on my 40D, runs on, focus, and takes pic

Thus, it's not the Canon mount change from FD to EF that's at issue here.

but about every tenth pic it will give me an error message say the lens and the body are not communicating, please clean contacts. Can anyone give me any insight? I did do some reseach and it appears at one point you could buy an adapter, but from what I have read that is no longer an option.

The adapter is not the resolution to the problem you're having. The adapter was made to accommodate Canon's old FD lens mount lenses to the new EF mount bodies. The FD mounts on the old lenses simply will not fit the new EF mounts on modern bodies without it. Yours fits, so it's not that.

Just F.Y.I. though, it's true that the originally made Canon adapters are very hard to come by, and are very expensive when they do come up for sale. Nonetheless, after-market adapters are readily available, in both chipped and non-chipped versions. I have one of each, and have used them to couple my Canon 500mm f/4.5 FD mount lens to my EF mount camera bodies.

As for contact cleaning, I've used pencil erasers with good success. For tougher grime, a bit of isopropyl alcohol can work, but try to get the most pure alcohol you can, free of scents and so forth.

For either, just be careful that you don't get excess into the camera body or lens. Use the eraser with the contacts facing down towards the floor so that any bits of eraser fall away from the body or lens, and inspect that they're free of any of that stuff before returning it to the upright position where they could potentially fall into the device. A twisting motion with the pencil works well on small contacts.

With alcohol or other cleaning solutions, don't over-saturate it. Use a Q-tip or, better yet, a lint-free cleaning swab. As with the eraser, it's best to work it with the contacts facing the floor so that nothing can drip or fall into the device you're working on. Look for and remove any fibers or other detritus after cleaning, and remove it.

If a good cleaning of the contacts doesn't solve the problem, it could very well be a problem with the electronics or even the mechanical components inside the lens, which would likely be much more difficult and costly to resolve, unless you're very good with disassembling, cleaning, repairing and reassembling somewhat delicate and precise instruments, such as lenses tend to be.[/QUOT

Wow thanks for all the advice! I will try that and see what happens. Since I got the lens so cheap I might be willing to stick a little bit of money into it but honestly I am not looking to spend a ton. I am gonna throw some batteries and a roll of film in the camera that came with it and see how it works on that.

 

[texkam]

Use the eraser with the contacts facing down towards the floor so that any bits of eraser fall away from the body or lens, and inspect that they're free of any of that stuff before returning it to the upright position where they could potentially fall into the device. A twisting motion with the pencil works well on small contacts.

This may be worth considering.
Kneaded eraser - Wikipedia, the free encyclopedia

 

[Buckster]

Use the eraser with the contacts facing down towards the floor so that any bits of eraser fall away from the body or lens, and inspect that they're free of any of that stuff before returning it to the upright position where they could potentially fall into the device. A twisting motion with the pencil works well on small contacts.

This may be worth considering.
Kneaded eraser - Wikipedia, the free encyclopedia

I believe it's the gritty texture of regular pencil erasers that is responsible for the cleaning of metal contacts.

 

[Dao]

OP, you said "about every tenth pic it will give me an error message". Do you really mean it stop working after you take 10 photos? A power on/off or remove battery without unmount the lens will allow you do shoot again until the 11 photos again?

 

[iolair]

ANY Canon branded EF lens will work perfectly on all of the current Canon D-SLR range.

The older Sigma lenses, having been reverse-engineered, have issues. I had a couple of pre-digital EF-mount Sigmas I used on my digital bodies briefly, and they would only work wide-open. As soon as I tried to stop down the aperture, I would get an ERR:99 on the top display when I pushed the shutter button, and would have to turn the camera off and on again to get anything else out of it. Sigma used to re-chip the lenses to work with the digital Canon bodies, but I'd be surprised if they still offer this service. If you put it on a film EOS body, it will likely work perfectly.

Now if I buy older lenses, I either go for Canon branded ones, or fully manual ones.