Production on a feature is simply "advanced pre-production". Many people (especially those who only do production) think that shooting the movie is making the movie. It ain't.
You make the movie in "post-production". You simply gather your materials for making the movie while you're "in production". And it is 100% counter-intuitive what you need to do on-set in order to get the stuff you need when you actually make the movie, months later. Also, your most expensive single days occur when you're in production. So it's understandable to think that shooting the movie is making the movie. It's just wrong.
So say I. So say we all.
But that's not what you're here for.
Photograph the person standing, feet apart, arms outstretched, palms toward camera, looking right intocamera. Long lens to reduce edge distortion. Use as diffuse and omni-directional lighting conditions as you can. Outside on an overcast day, for example. Basically, the less directional lighting the better. You don't want the lighting in the texture competing with the lighting in the 3d render.