Best Autofocus settings for Fashion or Sports... And more

[NNN636588477080053579]

Hi there,

I hope someone can help me, I own a Phase One 645DF+ camera with a P40+ back and I shoot fashion with a mix of sports. What do most people do when trying to capture motion using natural light or even strobes? Is it easier to use manual focus and get the timing down for when you'll click the shutter or is there a custom function that helps? I've tried using Continous mode and it doesn't do me any good. For example if the model is just walking towards you not even running. With running I'll just bring out my Nikon cameras.

Also, sometimes when I'm going in for a headshot, and I'm shooting at 2.8, it'll take me forever so it seems to focus on the eyes. Anyone else have this problem? Or should I just move my aperture up? Any help would be great, thanks!

[C-M-B]

The AF of the 645DF+ is "okay" but not really made for fast moving objects, especially not objects that move towards you or away from you at a high speed.

That being said you can still manage such shots quite well by proding the AF with a good contrast between subject and background and/or by working around the present limitations.
If for example the model is walking towards you, you'll need to either get the image in 1-2 shots or move back to keep the model in frame.
In the first case you can set it up so that the AF doesn't have to do a lot of hunting before you press the shutter (the model will only be able to walk a few steps before he/she is out of frame anyway). In the second case the AF won't have a lot to do except for compensating for small differences because you'll have to keep the distance somewhat constant during walking.

A lof is focussing problems are also related to the lens you're using and how fast/slow its AF is. If you're using a tele-lens in a dimly lit studio the AF will have a problem finding its target - and with 2.8 it's really hard to get it in focus at all and also very hard to keep it in focus.
The 645DF+ only has AF in the middle, so most of the time you'd have to focus and then reposition the frame for a composition - with f2.8 that's often enough to change the DOF and you'll lose sharpness in the eyes. Besides, f2.8 for headshots is pretty extreme, that's hardly enough for keep a whole eyelash in focus for headshots.
It's hard enough to get it done with f4.0 - but if I manage to do so, it's only with a tripod or Monopod on manual focus.

[NNN636588477080053579]

Thank you so much, will keep this in mind when I shoot next.