Add Your Canon EF and EF-S Lenses to M43

Interesting twist on adding lenses to your micro-4/3 system, active electronic lens adapters.

Having had Canon (D)SLRs for a long time, the lenses I own collected dust for the better part of the last years.
Lately, I learned that some manufacturers created active EF/EF-S to M4/2 adapters, allowing to control the aperture and the autofocus of Canon compatible lenses.
So, finally, I bought a second hand specimen of such an adapter. With the adapter in house, it was time to test it with various combinations of lenses and cameras.

Here are my first experiences:

1. Panasonic Lumix GF5
• Canon 50mm f/1.8 II - autofocus problematic
• Canon 18-55 EF-S kit lens - works perfectly
• Canon 35-80 EF (film) kit lens - works perfectly
• Sigma UC 70-210 EF (film) lens - total fail!
• Sigma 70-300 macro EF - works perfectly
2. Panasonic Lumix G3
• Canon 50mm f/1.8 II - OK
• Canon 18-55 EF-S kit lens - works perfectly
• Canon 35-80 EF (film) kit lens - works perfectly
• Sigma UC 70-210 EF (film) lens - sort of OK, focus might fail, but will grab in a second attempt
• Sigma 70-300 macro EF - works perfectly
3. Olympus OM-D EM5
• Canon 50mm f/1.8 II - good
• Canon 18-55 EF-S kit lens - works perfectly
• Canon 35-80 EF (film) kit lens - not great, but works, aperture displays weird behaviour
• Sigma UC 70-210 EF (film) lens - focuses only on the wide end, aperture weird
• Sigma 70-300 macro EF - works perfectly
4. Olympus E-PM2
• Canon 50mm f/1.8 II - good
• Canon 18-55 EF-S kit lens - works perfectly
• Canon 35-80 EF (film) kit lens - OK-ish
• Sigma UC 70-210 EF (film) lens - focuses on the wide end, aperture weird, shuts down during zooming
• Sigma 70-300 macro EF - works perfectly

Conclusions

The old film EOS (EF) lenses are essentially unusable. Maybe the Canon could be used on the E-PM2. IBIS wont work properly, since the old lenses don't communicate the focal length correctly.

The Nifty-Fifty struggles with the older camera, with the newer ones, it seems to be doing OK and is a usable portrait lens with great bokeh!

The cheap 18-55 seems to be making a great all purpose walk about zoom. The focal length is communicated correctly, so Olympus' IBIS will work fine.

Similar to the Canon 18-55, the Sigma 70-300 macro will communicate the focal length correctly. Autofocus could be better, but, this is a special purpose lens on MFT, reflecting an all purpose wildlife lens in an affordable and portable package.

Would it be worth to buy such an adapter and buy those lenses? I don't think so. Focusing is just too slow. However, if the lenses are already in your possession, such an adapter might be very useful to you.