There has been firmware upgrade for C-AF when used with high continuos shooting. 9fps. If you ready the Olympus e-group forum there are many pages about the issue. I have used a E-M1 since launch used it with 4/3rds and m3/4rds lens. Tried every type of setting but the C-AF performance is not very good. Some people have got better results using the camera in portrait mode, but this is a compromise not a solution. E-M1 struggles to acquire focus and doesn't always hold it. I have tried it on Motorsport and aircraft. The C-AF on E-5 was better. Sold all my 4/3rds lens bought a D3s and a couple of lens best thing I have done. Still got E-M1 as a light weight walk around camera where C-AF is not critical. Love the camera but C-AF and high ISO performance doesn't cut it.
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