On film, the resolution is dependant on the scanner and may be selectable. This translates into about 1800 x 2200 by 1024 shades of gray. Both cost and the quality are low. It isn't recommended. CCD's use a specialized fluorescent bulbs to shine through the film and CCD arrays as detectors.
Lasers use a laser to illuminate the film and photomultiplier as detectors.
Laser are also more expensive than CCDs. The technologies are quite comparable in achievable resolution - both can support 4k by 4k. Once you get above that ratio, there will be loss, regardless of the compression technique used. There are several well known methods of compression, including several newer methods, such as wavelet compression. They vary in the amount they compress data and the quality of the reproduced image, including the types of artifacts produced.