A couple of my favorite threads on this issue.

Quick Comparison of OM 50 1.4 to Oly 45

OM 50 1.4 vs. Oly 45 Part 2

My opinion is the 45 1.8 is better, but if you can handle MF, the 50 1.8 legacy lens is pretty darn close. I spent only $45 for my 50mm and $26 for my adapter.

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Jonathan
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www.jonathanfriolo.com

Thank you guys for all the info, its quite divided all your opinions but i guess im leaning towards the o45, because of the lightweight, af and compact size compared to a mf plus adapter.

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www.chrisleskovsek.com

At the end of the day, do you really want to depend on manual focus for your photography? Depends on what your goals are. I tried a couple 50mm legacy lenses with my first μ43 (GF1) and quickly decided that MF was not for me; when the Oly 45 arrived, my brief flirtation with legacy lenses was over and done. Three cheers for Auto Focus!

On the other hand, if you're a lens aficionado and want to incorporate the various special qualities of these lenses in your work, you have some workable options as described here.

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Chuck

I'm currently splitting my lens choices about 50/50 between AF and MF. The AF lenses tend to get used for P&S situations. The MF lenses when I really want to be in control of everything.

With the E-M5's IBIS and a high quality adapter, I'd say you can get pretty decent quality with MF nowadays. Plus I prefer the feel of a legacy 50 over the plastic build of the 45.

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Jonathan
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www.jonathanfriolo.com

Check out this thread for the results of some testing one of the other forum members did. In short, the O45 is an extremely capable lens.

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Sarcasm is my default tone, so please consider that before taking offense to the preceding message.

Criticism (no matter how harsh) is welcomed of ANY and ALL images I post.

There is a certain quality to the legacy 50mm I own (Canon FD1.4) that I haven't seen in pics from the Oly 45mm.

I completely agree the Oly is sharper, but that's not always as important to me as is going for a certain feel to the photo. The legacy Canon is plenty sharp and has more character - although I must admit "character" is completely subjective.

I'm sure you can get even better than "pretty decent" quality, BUT....you have to focus manually!! NOT FOR ME!

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Chuck

Well honestly, it doesn't matter how sharp the legacy lens is... if you suck at manual focus, the picture won't be any good.

I shot exclusively with manual lenses for over a year, and I get excellent results. I own the Oly45 now, but still shoot my manuals often. Why? Because I enjoy the tactile experience of shooting these lenses. Also I enjoy having COMPLETE control over the exact point of focus. I can never seem to get AF to focus on the area I want sometimes. That's been my experience anyway. The good thing about legacy lenses is, the price of entry is very reasonable. I've gotten some good lenses on ebay for $20-$30 bucks.

But if you have the money, by all means buy that Oly45. It is a very good lens.