There are three ways reciprocity failure were addressed. One is to put the film in an oven and heat it to a specific temperature for a specific duration, after which the film must be exposed and developed immediately. Heat does increase the sensitivity of some films, but it also ages the film faster and increasing fogging. It will not work on all films. Another is to chill it down to the temperature of dry ice during exposure. It works well, but then you have the problem of film becoming brittle as ice at -110F, frosting of the front window of the camera, and the fact you have to load each frame in total darkness in a changing bag. This is a major hassle to do, and again not all films respond well to extreme cold. A third, and the most practical for you is either placing the cassettes or rolls of film in a sealed chamber, then soaking it in a mixture of nitrogen and hydrogen gas. Better results are achieved when the film is places on reels or hangars, then placed in cassettes. The chamber must be light and pressure tight and often is heated to speed the process along. This is the most practical method for amateurs, but you need a gas cylinder and regulator, and a chamber in which to hyper-sensitize your film. This approach works on some films, but either will not work on others, or it will ruin them. It can induce chemical fogging as well, therefore the duration and temperature must be within certain parameters for success. You could use hydrogen alone, but remember this gas is explosive. Nitrogen can be used alone, but its not as effective as hydrogen or a hydrogen/nitrogen mixture called forming gas. It was sold commercially at one time, but now you'd have to find someone who could mix 8 percent hydrogen with 92 percent nitrogen. Once hyper-sensitized, you should use and process the film ASAP. Also, gas hyper-sensitization works by driving oxygen and moisture out of the film, therefore keep it sealed from air exposure and keep it refrigerated or frozen until use. Frankly, I would just opt for a DSLR or CMOS sensor camera and forget about messing with film. I am a former photographer who been down this path, and it's much harder than many realize. You will toss whole rolls of failed exposures into the trash before you get any semi-successful photos.
I have some experience with large format cameras too. Yes, the image quality is far superior to 35mm when it comes to prints of the same size. But few if any amateur telescopes could adequately cover 4 X 5-inch sheet film, let alone 8 X 10 sheet film. Unless you somehow have access to telescopes like the 200-inch Hale telescope in California, I don't know of any amateur instruments that can do that. There are amateur telescopes that can be used with medium format film successfully, but they and a mounting suitable for them are anything but cheap.
Edited by Achernar, 30 June 2018 - 08:38 AM.