Hi Eddie and welcome to this fantastic forum!
As an owner of a EOS 5D mk1 I can say that it is a great camera.
When I take pictures of my models I either use my EF 100mm f/2,8L macro or, if the room permits it, the EF 200mm f/2,8L.
In other words, I try to shoot from as far away as possible. Your EF 24-105mm f/4L will do a perfect job at 105mm.
I always use a very sturdy tripod.
Two advantages by shooting from a distance is the background and perspective control, and the light control.
Your flash is very powereful, so I think it will bw OK if directed towards a white ceiling or a wall behind you.
If directed towards a white ceiling, I would also use a white reflector from below the model.
In some cases, when shooting from a distance, a direct flash may work OK, but I would use one or two f-stops smaller than the camera metering says, by shooting in manual mode, e.g. 1/60sec and f/5,6 or f/8. f/8 will of course also make the depth of field better.
I make my best shots on a slightly clouded day, in the conservatory connected to our house, with three glass walls and a transparent roof.
In ambient ligh I use ISO200. Noise is normally no issue with the EOS 5D, due to the sensor size and the distance between the pixles.
My best advice: shoot and try!
Edited by user 21 January 2012 22:18:48(UTC)
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