Yes, this is known as cranial reciprocity failure. Briefly stated, the subject's head size varies in proportion to the length of the time of the exposure, up until a certain point, after which the subject's head will be removed from the photo altogether.
Try using faster film in order to keep from decapitating your subjects. Or, use a flash. On Tue, 6 Mar 2001, Kellie Deem wrote: > I am doing a project for my photography class and I am going ot make a > pinhole camera. I was researching some galleries and I came across a picture > of a man, whose head was gone. How did they do that? Does it have something > to do with the time? > > Kellie > kde...@hotmail.com >