D4 to OMD-EM5

It's actually quite good compared with my dslr, all except for focusing precision on the fly, meaning the focus point on a dslr is usually fairly pin-point, but the smallest focus point on an EM5 is still a square that sometimes chooses things you don't aim at. It's an area where m43 still has some work to go, though it sounds like the gh3 has made improvements here.

I found I prefer to turn off the focus assist light, as the lenses work about as well without it, and  I don't spray my subject with a red light, letting them know what's up. If I choose a high enough iso to brighten the scene (pulling down in post if desired) that seems to help low light focusing.

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John Krumm
Juneau, AK