Do adapters exist for old lenses to Canon's DSLR mount?

Question

I currently have a Canon 20D and happened to find a few old lenses.

Are there any adapters that can work for these lenses? I unfortunately haven't been able to find anything.

The old lenses I have are:
* Tokina SZ-X 352 35-200mm F4-5.6
* Minolta MD Rokkor-X 1:1.4 f = 50mm
* Sigma 35-70mm 1:2.8~4

Answer

It depends on the mount, and on whether you can accept an optical element in the adapter.

Canon's EF mount has a very short register, which means a lot of lenses for other mounts can be adapted simply with an adapter that moves the lens a few millimeters away from the mount. However, with other mounts you need to get a lens element to achieve infinity focus. This element can affect optical performance.

The lenses that can be used with an adapter without an optical element include, but is not limited to:

• Nikon F mount
• Olympus OM
• Leica R mount
• Contax/Yashica
• M42 screwmount

Lenses that require an optical adapter include, but are not limited to:

• Canon FD mount (old Canon mount before EF)
• Minolta MD

Unless a lens is very unusual, or you're strapped for cash, it's often better to get a lens that doesn't require an optical adapter, as the choices are large for the Canon EF system.

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