It all depeds on what you're shooting. A test I did rated the camera at 320 asa with camera settings at 720pn and an f5.6. With a red rock lens adapter and a 50mm nikon f 1.4 lens the lens and the camera at f5.6 it rated a 125. So with those measurements, the distance from your lights to the object and the distance from the object to the camera you could in theroy calculate how many watts of light you'd need. But if your looking for a general light kit I'd suggest