Which lens types fit a Canon 5D Mark II and cover full frame?

Question

I’m buying used lenses for a Canon EOS 5D Mark II, which is a full-frame Canon DSLR with the EF mount. I’m confused by the different lens abbreviations from Canon and third-party brands.

For Canon, I understand I should avoid EF-S lenses because they are designed for APS-C cameras. Is it correct that I should only look for Canon EF lenses?

For Sigma and Tamron, which labels indicate lenses that both fit an EF-mount DSLR and cover a full-frame sensor? I’d like to avoid crop-sensor and mirrorless-only lenses.

scottbb · Accepted Answer

The question, What do all those cryptic number and letter codes in a lens name mean?, and its answers cover this. But in summary, for your question:

Canon lenses

Only consider EF lenses. As you said, EF-S lenses are ~1.6 crop image circle lenses. EF-M lenses are for Canon's mirrorless bodies, and won't even mount on your camera.

Sigma lenses

You're looking for Canon-mount, DG lenses. If it says DN, it won't mount on your camera.

Tamron lenses

Di lenses. Di II are for crop-sensors, and Di III are for mirrorless cameras.

Nikon lenses

The option exists for Canon EF body owners to mount most old-school Nikon F-mount lenses, using a F-to-ES (Nikon-to-Canon) mount adapter. Older Nikon lenses will have manual focus and aperture controls, and will work fine adapted to your Canon body. If there is no "FX" or "DX" designation, it will likely work. 'DX' is a crop image circle lens, so stay away from those. FX is full-frame. Many FX lenses will 'work' on a Canon body, but depending on the quality of the lens adapter, it might not pass communications to the lens; especially if the lens has a G designation (which requires the adapter to physically control the Nikon lens's aperture). Also, make sure the lens has its own motor, not relying on the camera body to have a motor; AF-S and AF-P Nikon lenses will work on your Canon body.