So this is kind of a fine-grain question, but I'm sure some of you have dealt with this situation before.
At a recent shoot I was using a 28" soft box tilted straight down (coplanar with ground) basically putting light mostly straight down. I placed the (hair) model so that she was backed up a few inches from being directly under the softbox.
The good--light looks super dramatic and soft. The challenging: I wanted a little fill from underneath-especially in the eyes. So I have someone hold a large reflector (white) from below. The problem is that whilst this is in fact filling the eyes well, it's also filling in the neck--removing the darkness that helps define the chin well.
Are there any techniques for having a little better control of the reflector ?

