Another method of hypersensitizing is known as preflashing. It can be done with just a few materials, including an item that doesn't commonly figure into astrophotography - an electronic flash unit.
I found that Ilford Pan F and Kodak Technical Pan 2415 behave almost identically when hypered by preflashing. Therefore, it's a good idea to do the distance testing with the less expensive Pan F film, saving the more expensive Technical Pan film for fine-tuning and actual photography.
If you have an reasonably dark observing site, preflashing can be done at the telescope.
Done correctly, preflashing produces high contrast, detailed astrophotographs without the sophisticated equipment and cold storage required for gas-hypered film.