It is not designed for encoders that are needed to communicate positional angles to the computer, nor has any after market manufacturer saw fit to design, manufacture or market variable speed motors for the SP mount to slew to objects and track them. I selected Brian Kidwell's Deep Space Navigator for the computer-telescope interface and David Chandler's Deep Space computer program for the star atlas. I would have to manually slew the telescope to the correct position, then find, focus and guide. This system has proven to be reliable and cost-effective even if it isn't the latest and greatest. Imaging and Image Processing Knowing how CCDs work is necessary.
Film uses photographic grains, CCD chips have picture elements, known as pixels.
The astrophotographer who uses film is enslaved to the photodeveloper unless he has his own darkroom. The developer has an enormous amount of discretion in the color balancing of the image. Many of the films in use today give the night sky a greenish hue unless the developer takes great care during the development process. If the astrophotographer desires to post the images on the internet, the images have to be scanned as well. Scanning offers some advantages.