DVD Project Update - What is Telecine?

While editing frames on my Welcome clip for the project, I started wondering where some of the artifacts I was removing actually came from. I'm currently up to a little over 7 seconds in my 51 sec restoration project.

As a boy, my dad was into 8mm film and we had tons of home movies. The projector had two reels on it. He would mount the film reel on the top reel and feed it through the camera to the lower takeup reel. Pull down the screen and force us to watch the worst films I ever saw. Well most people, or kids that is, hate home movies. After all there was no sound and well...been there done that. Even the homemade popcorn wasn't that good. No telling what actually happened to those films but what I learned about films back then, helps me understand what I'm currently facing.

Telecine is a term which combines the words Television and Cinema. It is a process of capturing and converting cinematic filmstrips to a format compatible with television.


One of the things about film, is that eventually, the feed holes along the edges wear out or get torn etc. Sometimes the gears on the projector get worn also making the film deteriorate even faster. Dirt and dust eventually produce scratches on the film as it passes through the projector. What is peculiar though are the "horizontal Lines" I've encountered. You can see them in the snapshot to the right.

I seem to recall seeing a documentary at one of the drive-in websites with the owner/projectionist showing off his gear. The movies were on huge 1000' reels and they were mounted on a rack horizontally. It doesn't really matter which direction the frames are running on a film. All they have to be is one after the other. They can feed top to bottom, botom to top, left to right, or right to left. The horizontal lines leads me to believe the clip I'm working on came from a reel that the frames were displayed horizontilly and not vertcally.

Back in the Silent Film days, the early cameras were hand crank type. Cinemetographers would count over and over to get a rhythm going while shooting a scene at an approximate rate of 16 frames/sec. Billy Bliter, shown above, was one of the early famous camera guys. When sound films came along, they had to bump up the speed to 24 frames/sec so they could more acurately sync audio to the film and reduce flicker. Many of the cameras were motorized at this point.

Movie house managers, were often guilty of instructing the projectionist to run the films a little faster so the show would get over on time. The point here is that likely many of the movies I saw as a kid in the theatre, probably wasn't shown at the 24 frames/sec rate either. I didn't know any better then either.

Along comes television....

In the United States, the television standard is called NTSC which calls for 30 frames/sec. The European standard is called PAL and calls for 25/frames per/sec. Ok so here comes the problem...how do they get from 16 or 24 frames/sec to 30 frames/sec so we can see a movie on the tv?

In a nutshell the, telecine equipment "stuffs" extra frames into the output. I believe it is about every 3rd frame or so. Fortunately, this process helps smooth out the flicker because the human eyes see less movement between the frames.

Back in the days when I was a custom farm machinery designer, I designed a reel for a harvester for the John Hass Company that improved the efficiency of the harvester from 10% at 1mph to 80% at 3mph. The engineer and I got curious as to why it worked so well. We had a hole cut into the shield and mounted a 1000 frame/sec camera to see what was going on. Wow what a difference in quality! Anyway this story would be best told on another blog entry.

So putting all this together, I can see how dificult and expensive it can be to restore a film. It also explains some of the stuff I'm encountering in my own restoration project.

2 responses
I remember loading up the film projectors in grade school to watch, oh, whatever it was they made us watch. I was the class AV geek, though of course I didn't know much except how to feed the film in and not to touch the projector bulb, which was hot. I had no idea you designed custom farm equipment.
Heh! I was an A/V Geek First. I did that at one of the high schools I went to. Got me out of class early sometimes to go setup a projector, slide machine or an overhead projector.