My Scott Kelby PS book has a section on studio work using this type of unit placed below the subject.He uses it in curves, and uses the eyedropper on the piece he wants,then crops out the tool.
Dave
> http://www.adorama.com/WEDT24.html
>
> An update on the 18% gray card. It they would make it smaller (12
> inches, say) I would be interested.
>
> Not that I really have too many exposure problems, since I use
> center-weighted averaging. I have had some burned-out highlights, though.
>
> Joe
>
