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Although film currently has the advantage over video in image quality, its weight and volume rule it out for the main camera work in the Artemis Project reference mission.
Heavy stuff
From personal experience from working with the finished print in a theater, it takes 6 20-minute reels of 35mm film for a 2-hour movie, and those reels must weigh about 10-15 pounds each.
Assume 35mm film weighs 10 lb for 20 minutes, or 1/2 lb per minute.
Assume 70mm weighs twice as much, or 1 lb per minute.
Assume we want 100 hrs of 70mm film (a shot in the dark). 6,000 lb.
That's half the weight of our habitat. (Estimates for the weight of the initial lunar exploration base are in section 4.1.)
Radio waves don't weigh much
Recording on video tape or disk would be a much less massive alternative, but transmitting video on the downlink is even better. Electrons are really light, and available in situ (via solar power, of course). We can trade a heck of a lot of communications equipment for the weight of that film.
Video is catching up
Video technology is rapidly catching up to the image quality we can get from film. For still frames, we can get up to five times the resolution from a video camera by making multiple exposures of the same scene and slightly moving the focal plane in between shots. This technique gives us more information to process the edge detail on small subjects in the camera view and eliminates the grid pattern inherent in electronic photography.
We can reasonably expect that full-motion, high-resolution video photography will come along soon. So we'll be able to photograph the images we want. Now all we have to do is get the information home.
A lot of bytes
If we plan to show these images on the big screen, we have to record HDTV as a minimum requirement. That's a lot of bytes to sling around. If we try to send the raw data to Earth as the images are recorded, we will quickly saturate any downlink bandwidth we can reasonably expect to have.
We've had a lot of discussion of video compression and image enhancement techniques that will reduce the bandwidth requirements by an order of magnitude or more, but developing a complete plan for handling video downlink still remains in our list of forward work.
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