David Cronenberg said this quote

She and Naomi had joked about the sexuality of camera apertures, that they needed to write a woman’s monograph on the symbolism and cultural relevance of the mechanics of image-making as it related to sex, so that, for example, stopping down the fixed 35mm lens’s diaphragm – elegantly composed of nine shutter-leaf blades – to a tight f/16 would be the equivalent of a Kegel pelvic floor exercise.