Gents,
Grounding circuits perform several functions and each has its requirements in terms of design. Safety is a number one requirements, and for this the ability to pass a fault current to a ground reference (earth) instead of through your body is the primary design goal. This "design" however effective for safety does not mean it's a good RF (radio frequency) ground. Safety grounds require a good low resistance path to ground; RF grounds require a good low impedance path to ground. As the RF frequency rises, your reactance (impedance) of the ground circuit rises. For your "black" background, you want to ensure the best low impedance ground for your equipment, i.e. very large gauge ground conductor or flat copper strap to a ground rod, shortest path possible from equipment, and use a termination ground (single point) from all your gear. No special stuff here, my studio grounding system is less than $200 worth of materials. Noise mitigation from your power line is a whole other science I'm sure has been discussed in length - I use brute force L/C filters and isolation transformers, but the grounding considerations are the same. (In the "old days" we used motor-generators for clean AC).