If one goes with film, the choice of a specific film is crucial. Many fine choices are available if all you want is star fields, but if you want the glorious reds of hydrogen-emission nebulae (think North America Nebula, Orion Nebula, Lagoon Nebula), the field is narrow. The human eye has relatively poor sensitivity to the very deep red of the H-alpha wavelength, and most films are understandably made to mimic the sensitivity of the eye. The result is that many films just won't show those nebulae at all.
One film I've found worth using is Kodak Supra 400, a professional film which you may have to order. I get mine from Adorama.com .