for cost reasons, cameraman fritz arno wagner only had one camera available, and therefore there was only one original negative. the director followed galeen's screenplay carefully, following handwritten instructions on camera positioning, lighting, and related matters. nevertheless, murnau completely rewrote 12 pages of the script, as galeen's text was missing from the director's working script. this concerned the last scene of the film, in which ellen sacrifices herself and the vampire dies in the first rays of the sun. murnau prepared carefully; there were sketches that were to correspond exactly to each filmed scene, and he used a metronome to control the pace of the acting.