I was recently asked to shoot the rehearsal of a dance performance at La Raffinerie in Molenbeek (Brussels). The studio was windowless and the piece is choreographed – for three dancers, a musician and a reader – with almost no lighting except low spotlights of varying intensity on three sides. The Nikon D810's autofocus is supposed to be miraculous in low light, but in light that low it really didn't work at all. The dancers were in contuous movement and I couldn't afford to wait while my lens hunted up and down for something it could get a grip on, so I switched to manual.
I found it strangely liberating. Often, there was not even enough light for me to judge the focus in the viewfinder. But I was making choices, and sometimes I deliberately chose to soften the focus on what would normally be considered the subject.