I use a Sony handycam on a tripod, 30 Watt 5000k daylight bulb 90+ CRI, no flash, that way you get true colors, no reflection or light refraction. I had to experiment for a long time, cheapest I found to be best and easiest. I have color cards I use for background. Grey Felt I have found to be the best all around neutral color though I do use both black and white depending on the marble.