Using an old EF lens on a 200D question/problem

Hi,

I'm reasonably new to DSLR (and photography in general).

I inherited an old Canon EOS 750 (35MM), with a Sigma 28-70mm EF lens, which I just recently tried on the 200D body.

The autofocus works, but when trying to take a photo the camera crashes out with 'err 01' failed to communicate with lens.

I tried cleaning the contacts, but that didn't solve the problem. Does anyone have any suggestions  of what else I could try?

From live view the lens looks like it would preform really well, especially in low light. Would be a shame for it to just sit in a draw.

Also, I'm thinking about purchasing some extension tubes and reversing rings, for experimenting with macro shots (on a budget).

Does anyone have any experience using these with the 200D, or would they have the same 'err 01' issue, as the reversing rings have no contacts?

Thanks in advance, Google couldn't provide me with any answers..

It happened to me as well.  I had a lens from my film days.  It turns out that even though it fits on the camera, a contact is missing.  So, won't work.  That's what happened to me.  Good luck.

Same problem with a old Sigma telephoto, the only workaround is using the max . aperture of the lens. example f3.5.  (Setting in the AV in the dial).  Otherwise buy a original Canon (digital or film era) or buy a brand new third  party lenses.

Very often those old 3rd party lenses will work if you shoot wide open at f/3.5 or whatever the widest aperture is.

Canon does not share the details of their technical protocols with third parties, therefore companies like Sigma and Tamron must "reverse engineer" them in order to create compatible lenses. Unfortunately, that means when new cameras come out, there is no guarantee of compatibility.

Sigma, for a long time, offered a one-time "re-chip" upgrade of their old lenses for compatibility with newer cameras. I don't know if that is an option anymore (I doubt it). Their newest lenses (in the Art, Contemporary, and Sport series) can use the "Lens Dock" to reprogram them at need, so this shouldn't be a problem going forward.