Loop Lighting
Loop Lighting is similar to Rembrandt lighting however the shadow from the nose does not meet the shadow on the side of the face.
This is a single light setup where the key light is set about 45 degrees to the face and a little higher than in Rembrandt lighting, you will find you have to adjust the angles and height to get the right shaped shadow, a modeling light helps a lot here. the true angle will not be 45 degrees but will vary according to the shape and length of the models nose.
Loop lighting did not seem to need the flag or blocker used in the Rembrandt setup as the reflected light helped with the illumination of the dark side of the face, which should be filled with more light than the Rembrandt setup.This setup can work for men and women as it is a little more flattering, it was often used alongside the butterfly lighting for some of those classic Hollywood posters.
Here is the basic setup for loop lighting:
And here is the 3D render from Set A Light:
And again I took the theory into the studio for some practice:
