Sigma DC and Tamron Di-II lens compatibility.

[TylerW]

I have a 10d, which means that I can't use EF-S lenses. Ostensibly I wouldn't be too bothered by this, except that I've taken a recent fondness to very wide glass, and there's some tempting options in that lens range. Sigma DC lenses, as well as the Tamron Di-II lenses are specifically for crop factor camera bodies, but does anyone know if the mounting flage on these lenses is the same as a Canon EF lens (which means they should mount up just fine) or if they are the same as the EF-S mount flange, meaning I'd be left out of all the fun.

Also, when lens manufacturers talk about the zoom range of crop lenses, are they still listing the zoom range in 35mm terms, as in "10mm (16mm on APS-C)" or are they listing those numbers post-crop-factor conversion, since those numbers don't really have any meaning because they can't mount up to any cameras with a full frame sensor?

[SCS_Photo]

I have a 10d, which means that I can't use EF-S lenses. Ostensibly I wouldn't be too bothered by this, except that I've taken a recent fondness to very wide glass, and there's some tempting options in that lens range. Sigma DC lenses, as well as the Tamron Di-II lenses are specifically for crop factor camera bodies, but does anyone know if the mounting flage on these lenses is the same as a Canon EF lens (which means they should mount up just fine) or if they are the same as the EF-S mount flange, meaning I'd be left out of all the fun.

Also, when lens manufacturers talk about the zoom range of crop lenses, are they still listing the zoom range in 35mm terms, as in "10mm (16mm on APS-C)" or are they listing those numbers post-crop-factor conversion, since those numbers don't really have any meaning because they can't mount up to any cameras with a full frame sensor?
Not a canonite, so I can't help ya on the first part. (though I've wondered about the same thing)

As for the focal length thing... They don't apply the 1.6x factor. So it would be a 10-22 or a 12-24 if mounted on a full frame, even if it can't be be. So the 10-22 comes to 16-35.2mm "equivalent"

[DoctorIt]

The DC and Di lenses will work just fine on your 10D. They are optimized for the APS-C sized sensor, but the depth of the elements is standard, they didn't follow Canon's EF-S lead here, and kept it "safer". By designing for C sensors, they can shrink the diameter since the coverage area is smaller.

[ziggy53]

The DC and Di lenses will work just fine on your 10D. They are optimized for the APS-C sized sensor, but the depth of the elements is standard, they didn't follow Canon's EF-S lead here, and kept it "safer". By designing for C sensors, they can shrink the diameter since the coverage area is smaller.

:agree

Additionally, the Canon EF-S lenses have a protrusion/extension which prevents their use on non-EF-S bodies. Some EF-S lenses have been successfully "modified" by users to fit the Canon 10D body.

See the following links for more details:
http://www.bobatkins.com/photography/tutorials/efs-10d.html
http://en.wikipedia.org/wiki/Canon_EF-S_lens_mount

[TylerW]

The DC and Di lenses will work just fine on your 10D. They are optimized for the APS-C sized sensor, but the depth of the elements is standard, they didn't follow Canon's EF-S lead here, and kept it "safer". By designing for C sensors, they can shrink the diameter since the coverage area is smaller.

Just the info I was looking for. Thanks Erik!