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  1. Hi, 'My first post'
    I have some 1960s standard 8 film, and I'm trying to copy it using digital cameras. I simply projected onto a screen and aimed the camera, but I get flicker, so completely useless.

    Can anyone tell me what methods are usually used please?

    Camerart.
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  2. Member
    Join Date
    Mar 2008
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    United States
    Search Comp PM
    Film Scanner ?
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  3. Member
    Join Date
    Aug 2010
    Location
    San Francisco, California
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    Reduce your shutter speed to 1/60 second or less. If your projector has variable speed control, you can tweak it to reduce flicker further. Experimentation is required to find the best combination.

    The best way to convert motion picture film is frame-by-frame scanning.
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  4. [edit]I see that JVRaines posted the exact same advice while I was typing my long post. If you can't get through everything I wrote below, just follow his much more succinct version.[end edit]

    The proper way to transfer film is to use a "frame accurate" transfer system. There are various technologies to achieve this, but what "frame accurate" means is that you get exactly one frame of film onto one frame of video. By contrast, the "point the camera at the screen" method always gives you blends of adjacent frames of film. This happens for two reasons: the frame rate of the camera is not the same as the projector; and there is no synchronization between the projector and the camera. Even if you set the projector and the camera to 24 fps, they still wont' be operating at the same speed.

    The flicker you are getting is caused by the fact that the projector has a shutter which closes each time the film is advanced to the next frame. In order to minimized the flicker that your eye perceives, most projectors use a shutter system that closes the shutter twice for each frame of film. This is done to increase the flicker rate so that your eye and brain don't perceive the flicker (flicker gives people headaches). If you have a projector that only opens the shutter twice for each frame of film, you can end up with some frames where the camera gets the entire frame without seeing any of the time that the shutter is closed. These frames are bright. Then, as the timing between the camera and projector drifts, some of the later frames will be captured by the camera during the time the shutter is closed. This pure black is averaged with the time the image is projected, and that image comes out darker.

    This is what causes the flicker: some frames are averaged with black and others are not.

    If you don't want to pay for a service that uses frame accurate services (which is what I would recommend that you do), you can minimize the flicker with the following techniques:

    1. Use a five-bladed projector. These were sold about thirty years ago specifically for doing the kind of transfer you are doing. By increasing the number of blades, this also increases the number of times the shutter is opened and closed for each frame of film. This means that some frames include four shutter closings and others include five closings. This is only a difference of 20%, so the flicker is far less. The more times the shutter closes, the closer each image exposure will be.

    2. Change the shutter speed on your camera. To understand why this helps, think of what would happen if you used a 1/1000 shutter speed. If the camera takes its picture during the part of time that the shutter is closed, it will record pure black, and will fail to capture any of that frame of film. At the other extreme, if you use a 1 second shutter speed, you will record a mish-mash of multiple frames of film. Since the projected image doesn't move, and since the movement of the film when it advances is blocked by closed shutter, you can set the shutter as slow as you'd like, without worrying about introducing any motion blur. Therefore, you want to set the shutter to roughly the fps speed of the projector. So, if your projector is running at 18 fps, you can set the camera shutter as low as 1/18 second. In practice, you'll want to set it a little faster than that. By setting a slower shutter speed (the default is usually 1/60 for NTSC and 1/50 for PAL video cameras) you increase the amount of time the camera records the film so that the percentage of that time during which the shutter is closed becomes less.

    3. Change the projector speed. Not all projectors have a speed control, but if yours does, play with this along with changing the shutter speed. Between these two, you can minimize the flicker.

    You can also apply a deflicker filter after you've captured the film. The filter for AVISynth and it is called Deflicker. Other AVISynth plugins can also reduce flicker, even when it is not their main purpose. For instance, if you use MVTools2 for denoising, setting the DCT setting to 1 and it will reduce a lot of flicker.

    Finally, if you want to do further restoration on your captures, you might be interested in this person's technology for improving film transfers done the way you are doing them:

    The power of Avisynth: salvaging "botched" transfers of old 8mm films to DVD.

    BTW, one of the many other problems you will encounter doing what you are doing is that you will get a hot spot in the center of the frame. You can eliminate this, as well as dramatically increase resolution if you get a telephoto lens for your projector, and then point your camera directly at the projector. You'll need to figure out how to dim the bulb (or simply install a low-wattage bulb). You can also use a neutral density filter on your camera. If you get the correct lens and have enough telephoto on your camera, you can capture the image without having to project it. This gets rid of all the scatter you get from a screen; it eliminates the hot spot; and you get a really sharp image. The image below shows a slightly modified Carousel projector that I use to quickly "scan" slides. I have a very nice Nikon slide scanner, but it takes 90 seconds per slide. By contrast, I can capture about 12 slides a minute with this rig.

    Image Attached Thumbnails Click image for larger version

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    Last edited by johnmeyer; 18th Nov 2018 at 21:22.
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  5. Hi,

    The old projector, I've borrowed, is struggling to keep going, and can't change speed, so I'll try the individual frame method.

    I may have a single frame feeder for the film somewhere in the shed, from an old shop film processor. I'll see if it takes 8mm or 16, and hopefully will convert easily, then connect a camera with macro or similar lens.

    Thanks for your replies, especially the detailed one.

    C.
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  6. I was NOT suggesting that you use a slide projector to transfer movie film. I only included that picture of my 35mm slide projector setup to show you how you can capture the image directly, without projecting onto a screen.

    I frame-by-frame transfer of movie film (a.k.a. "frame accurate") is done with a modified projector that has some sort of trigger added to tell your camera when to take a picture. You then use either a video camera or still camera.
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  7. Hi J,
    I understand, this is why I mentioned the single frame feeder. I dug it out of the shed, and it is for 16mm, so will need modifying to transport 8mm. In case you didn't know, 16mm used to be used in miniature cameras, instead of 35mm.

    I'll make a trigger connected to both the camera and the feeder.

    C.
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