Originally Posted by GaryAyala
I'm using center focus only, the smallest I can make. How does your focus arrangement(s) compare?
That's exactly what I do, Gary.
And - although I've already explained some of this above: here comes a post with all my recommendations for using the E-M5's C-AF:
First of all: use the minimised AF field. If your subject is further away and the AF field also is filled by other stuff, it can happen that the camera focuses on something that features more and clearer contrast lines.
Next: Due to what I've explained above, forget C-AF tracking as the AF field can't be minimised in this mode. It possibly can be helpful for shooting big moving objects like cars (haven't tested it but it could be) but it's useless for smaller subjects. In C-AF without tracking, it's up to you to keep the AF field on your chosen subject (something that's quite a challenge as the visible AF field disappears in the burst mode as soon as you have pressed the shutter button, so quite a lot of practicing is needed). But it pays off, as you can see. If you succeed in keeping the AF field on the moving subject, the C-AF works rather well.
Next: Use picture mode vivid. It increases the reliability of the C-AF significantly. When I used the camera with the adjustments I was accustomed to from my E-5 and my E-PL3 (natural, sharpness -2, contrast -1, saturation default, noise filter off), the C-AF more often than not didn't even start to 'bite' (don't know the appropriate English word) and so, a series weren't sharp from pic one. In vivid however, ( with the settings saturation and sharpness default, contrast +1), the C-AF proves to work just as reliably as the one of my E-5 (please note: as reliably doesn't mean as fast as. I still doubt if the E-M5's C-AF could cope with the shallow DOF of lenses such as the ZD 50-200 SWD 2.8-3.5, even if it would C-AF at full speed, on the E-M5. But that's another story.).
Next: Enable IS1 and the EVF IS. I know - we all have learned that you mustn't use the IS when shooting action - but that's a lesson of the DSLR days that arguably doesn't apply to the E-M5. Don't ask me why - I could only guess - but the IS and the EVF IS also increase the C-AF performance.
Next: You should switch the EVF picture rate to high. Makes following you subject easier.
You are aware of the fact that the C-AF only works in burst mode L (up to four pics), aren't you?
Next: Use shutter priority with the 75-300. With the 40-150 or 14-150, however, shutter priority off also seems to work fine without reducing the FPS rate significantly.
And finally: forget the DSLR lesson that told you to allow your camera half a second for pre-calculating the speed and direction of the movement of your chosen subject. Well, that proves to be counter productive when it comes to the E-M5. Just aim at your subject, wait for the confirmation beep and shoot immediately.
By the way: the practicing could turn out to be rather frustrating at the beginning as the lack of orientation due to the invisible AF field really tends to make the task of keeping the AF field on your subject really difficult. But don't give up to early. You will be rewarded with great pics.
But for the moments of frustration I'd like to mention that the S-AF of the E-M5 - and the latest PENs too - also is fast enough for action shots. Just aim at your subject and press the shutter button in one go without waiting for the AF confirmation. You will be amazed about the results. You can't shoot series this way (although you will be able to shoot three FPS - but keeping the camera steady is really difficult if you are pressing the shutter button again and again) but at least you will have something to be happy about on your memory card.
Once again: good luck!
And - I nearly forgot: It seems as if the Panny zooms are much better suited for video C-AF - I was told that in this area (I don't shoot videos), they focus more smoothly, with the M.Zuikos tending to pump. But for action stills, the M.Zuikos apparently are better suited. I have tested the E-M5's C-AF with the following tele zooms: M.Zuiko 14-150, 40-150 and 75-300 on the one hand and Lumix 45-200 and 40-175 on the other - and another user in a German forum made a direct comparison with the M.Zuiko 75-300 and the Lumix 100-300. The result: All the M.Zuikos are cooperating clearly better with the C-AF of the E-M5. Even the Lumix 40-175 - that seems to be the µFT AF-speed king in S-AF, to me - is not up to the task of C-AF-ing on the E-M5.
It's rather annoying as it seems to mean that those who do video and action-stills and tend to use the C-AF while shooting video will either have to decide for a priority or have to purchase the respective lenses twice - but that's how it seems to be at this point in time. A video optimised lens isn't ideal for shooting action stills and vice versa.