I got the chance to borrow an Olympus M. Zuiko Digital 60mm f/2.8 from a friend just before Christmas and so in this post I will show example images made from it and the Micro-NIKKOR 55mm f/2.8 (used with a Fotodiox Nik-m4/3 adapter of course). Don't expect to see a technical comparison. I'm going to simply let the images speak for themselves.
You can see in the images above that the 55mm Nikkor lens is taller when fully extended. Not by much if you remove the adapter or when it's not extended but I included it because you cannot use the Nikkor lens on the E-M5 without an adapter of course. The ZD60 is also smaller in diameter plus it is made of plastic compared to the all metal Nikkor. So you can imagine the weight difference! A grip on the OM-D is highly recommended when using the Nikkor although I was able to use it without a grip but of course it's not well balanced and it will require some getting used to. The ZD60 will also focus 1:1 while the Nikkor is only 1:2. And the two key differences for me, the ZD60 autofocuses while the the Nikkor is manual focus only and the price obviously. The ZD60 is $499 CAD brand new while I got my used Nikkor for around $100 on eBay. I would guess the ZD60 will sell used for around $300 or more.
Ok, so what about sharpness as that is most often asked? In my eyes they are about the same. Both lenses produce really sharp images and I think the Nikkor just about matches the ZD60. One major problem with the Nikkor is CA. It's ok for me though, I can live with it. For an amateur and hobbyist like me, the 55mm f/2.8 Nikkor lens is a great cheap alternative for macro and product work. I'd still get the ZD60 though if money is not a problem.
Here are example images as promised. All images were shot in RAW and processed using my workflow. I normally import the RAW files using LR and apply minor corrections before editing and processing in CS4. Enjoy!
Images from the ZD60:
And here are example images from the Micro-Nikkor 55mm f/2.8 AI-s:
To see technical details about the Micro-NIKKOR 55mm f/2.8 AI-s please click this link and to see a review of the ZD60 please click this link.
All images in this post were taken using an Olympus OM-D EM-5 and E-P1. For the lens images I used the M. Zuiko 45mm f/1.8.