I've long read arguments for using a focal length of between 85mm and about 105mm. But I read an article somewhere about doing headshots with a 200mm lens. Also outside this "normal" focal length for portraits is the 77 Limited. But I heard people talk about it and I saw images that made me oo and ah. So..
I wanted a FF body for this because the way it creates shallow depth of field is more pronounced. We can do the whole circle of confusion discussion later or just search it out.
Camera: Pentax K1
Light: 7pm golden hour and a 30" or so round scrim.
Model for the project: Tasia Larkin
ISO 400 200mm f/2.5 1/400th Tripod mounted.
ISO 400 77mm f/1.8 1/125th Hand held.
Both lenses are nice but the 77 Limited is easier to use. It often does not need a tripod and with auto focus I nail focus more often. The 200 f/2.5 is harder to use but it does obliviate the background and compress the subject.