8mm Forum: Conversion to digital

This is topic Conversion to digital - lots of flickering in forum 8mm Forum at 8mm Forum.

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Posted by Mandy Leo (Member # 227) on December 15, 2005, 04:37 PM:

I have a question : is it the nature of the beast that there is flickering when converter 8mm to digital using one of the those cheap telecine converters (projector one end, DV cam in the other)? I wasn;t sure if it was just me or that is what all transfers look like...maybe it is my eumig624d projector?

Posted by Michael De Angelis (Member # 91) on December 15, 2005, 04:55 PM:

Mandy,

Transfers from all projectors to camcorders will result in flicker. The key is to keep the film shutter in speed with the camcorder. If there is an speed adjustment on the projector, you will need to increase the speed up to 20fps.
(frames per second) Otherwise, you will need a projector with a 5 bladed shutter or one of those transfer machines that perform the conversion.

Otherwise, there may be a method to use Pro software and make the conversion through the computer.

Michael

Posted by Mandy Leo (Member # 227) on December 15, 2005, 06:49 PM:

Interesting,
what pro software might take out the flicker?

Posted by Kurt Gardner (Member # 440) on December 15, 2005, 07:58 PM:

Does your camera have different shutter speeds? I have a Sony Digital 8, and in the special effects menu, there are three shutter speed choices. I choose the one that reduces the flicker the most; the only drawback is that scenes of movement might be a little "smeary". Still, the results are great for a homemade project. Regarding the converter, I've tried them and find that I get the best results just using a tripod and shooting it right off the screen.

Posted by Alan Rik (Member # 73) on December 15, 2005, 08:45 PM:

I have had great results using the GS1200 Projector and a Sony DCR-TRV10 Digital Camera. I pointed the camera at the screen and using the built-in LCD Monitor I sped up the film until the flicker disappeared. Of course the contrast wasnt the greatest BUT for a home transfer it was perfect for me.

Posted by Jan Bister (Member # 332) on December 15, 2005, 09:57 PM:

Workprinter-XP

Expensive, yes, but it's one option I thought should be mentioned here.

Posted by Jean-Marc Toussaint (Member # 270) on December 16, 2005, 03:14 AM:

It's expensive, indeed, but the test films on their website are impressive.

I have one of these telecine converters. I run the film at 25fps (something that your 624 can't do, unfortunately, as far as I recall), projecting the smallest image possible, with the camera shutter set at 1/50. No flickering. Then I do some colour timing and slow the film down (if needed) in Final Cut Express. The result is OK but not extremely sharp. And there's still the hot spot issue.

Posted by John Whittle (Member # 22) on December 20, 2005, 10:04 AM:

quote:
I have a question : is it the nature of the beast that there is flickering when converter 8mm to digital using one of the those cheap telecine converters (projector one end, DV cam in the other)? I wasn;t sure if it was just me or that is what all transfers look like...maybe it is my eumig624d projector?

What you have to do will depend on the television standard where you live. If you're in the US, then the NTSC standard produces 30 pictures per second (nominally, in color it's actually 29.94 due to timing differences with the color subcarrier).

In order to transfer film to video, you must match up the frame rate of the film to the field rate of the video with a whole number.

Thus 30 frames of video is made up of 2 fields each and yeild a number of 60.

If you take silent film and a projector with a three blade shutter and run it at 20 frames per second you'll get 60 interruptions and match the video field rate. If you want to run a slower speed (say 15 frames per second, 16 won't work), you'll need a four blade shutter and then you get 60.

If you have sound film, then it's 24 frames per second and a five blade (interruption shutter) and you'll get 120 which is equal to 2 x 60.

To get rid of the ground glass effect, you'll need to set up an aerial image table which consists of a diffusion glass behind the projector aperature and a field lens. Then the image is created in thin air (just the way Donald Duck danced with Carmine Miranda) like a film chain. This produces the best contrast and sharpness and can be a bit diffcult to set up since it is really an optical bench. To get your image correct left to right, you'll need a front surface mirror in the set-up.

A synch motor on the projector will help matters, but if you have a good solid state speed controller built in your projector (and not a simple induction motor) you probably can get by with that. An iris on the projector lens will help in setting the light output of the projector. Putting a resistance on the lamp will change it's color as you lower the lamp output.

John

Posted by Joe Taffis (Member # 4) on December 20, 2005, 06:24 PM:

Thanks John, ya got that Mandy???? [Smile]

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