If you are referring to that clear metal halide as a light source (bulb), you do not want to do that. It, as well as most LED's are not a chromatically correct light source. They are both weak in areas of the spectrum and will give you an incorrect color rendition of some colors in the image. You would be better of to use flash if you are going to do portraits. Not only for chomatically correct images, but also for freezing subject or camera movement.