Canon EOS Elan and Tamron lens vignetting

[C0nnie]

I've recently started using my Canon EOS Elan with a Tamron AF 17-50mm f/2.8 lens. The developed photos all have a dark vignette around them, which I have never seen before when using either the camera or the lens separately. Is this lens not compatible with the camera, and if so how do I know which lens will be compatible? 

Thanks!

#CanonElan #Tamron

[jrhoffman75 · Accepted solution]

The Elan is a 35mm film camera. The Tamron lens is designed for a digital APS-C size sensor, which is smaller. Image circle won't fill the film frame.

[C0nnie]

Oh I see. Thank you for your help!

[normadel]

I have three different EOS Elan cameras, and a full-frame EOS 6D DSLR. I have Canon EF-S lenses for my crop-sensor bodies. I cannot even mount the EF-S lenses on the Elans or the 6D.

It is designed that way, for good reason.  EF-S lenses would cause mirror damage on full-frame bodies, film or digital, if they could be mounted. The rear of the lens sticks out past the bayonet flanges. Putting this lens on a full-frame body would let the mirror  hit the lens.

Even if Tamron designs its Canon-mount APS-C lenses so they can mount on a full-frame body, they are doing an injustice by not making it clear (for the unknowing) that vignetting will result. In the extreme, you can get a circular image, which is the whole image circle being transmitted by the crop-sensor lens, which is smaller than a full-frame image area.

[jrhoffman75]

No third party lenses have been released with an EF-S mount. Only Canon lenses have EF-S mounts. 
Third party lenses use the EF mount and various descriptors to identify their compatibility. Tamron uses Di II. Their catalog material states clearly that Di II design lenses will produce circular images on conventional cameras or full-frame sensor DSLRs. 

[normadel]

I'm looking at a B&H catalog from a few years ago. Sigma and Tokina both had (have?) lenses expressly for APS-C for Canons, Nikon and others. If they are mountable on a Canon full-frame body and don't interfere, fine. Maybe unfortunate though.

But figuring out their lens designations  for APS-C versus full-frame is something a more-casual-than-us user would not know to do.

[krahe]

Did you mean to say "full frame sensor DSLRs" at the end of your comment rather than "APS-C sensor DSLRs?" I'm not trying to be picky - just want to make sure in case someone with less knowledge under their belt comes along looking for answers.

[jrhoffman75]

You are correct. Thanks for catching. Response edited.

[ebiggs1]

As some here on the forum know lenses have been my hobby for the last 20 years until recently abandoning it

At any rate I think I have tried and I have adapted every possible way there is to use a lens. And although I don't recommend it  you can modify an ef-s lens to work on a FF camera. Unless you are at close focus there is little concern about it interfering with the mirror. Now that said, again I don't recommend anyone do it, and I have not tried it with every ef-s lens out there. Close focus can be and most likely will be a big problem with most ef-s lenses on a FF camera. There is less chance if the camera in question is the H-sensor like the older 1 series.

I bought only a very few any off brand crop sensor specific lenses but JRH is correct, "No third party lenses have been released with an EF-S mount." 

Misinformation abounds like one previous post.