8mm Forum: Flicker help

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Posted by Alex Wilson (Member # 6247) on January 08, 2018, 02:55 PM:

I’m a newbie at this and could use some advice...
I have a chinon 2500GL using it in super 8mm mode... trying to digitize and record the picture with a Sony AX100 video camera.

What would the best recording speed be to reduce flicker on the Sony?
What is the optimum distance or size of the picture (Distance)?

Thanks for your help..

Posted by Paul Adsett (Member # 25) on January 08, 2018, 03:06 PM:

Alex, your best bet to reduce, or even eliminate flicker on the video camera, is to experiment with the shutter speed on the camera. I use a Bolex 18-5 projector for 8mm transfer, but it has a fixed 18fps. To eliminate flicker I adjust the shutter speed on my Sony video camera until it is no longer visible.
To do the transfer I just project the film onto a sheet of 8 x 11 printing paper. Works fine.

Posted by Alex Wilson (Member # 6247) on January 08, 2018, 03:49 PM:

Thanks Paul for the quick response
The chinon 2500 has an adjustable speed, the Sony has different shutter speeds
Seems to be infinitely adjustable, is there a shutter speed bench mark to start at?

I seem to be getting flutter on auto but have not tried manual adjustments, I am only testing it without film, will that change once I load film in it?

Aw.

Posted by Mark Mander (Member # 340) on January 08, 2018, 04:12 PM:

Alex,as Paul said adjusting the shutter speed is your best bet,I slow the shutter down and do a bit of small adjustments with the projector if needed,you don't want to slow the shutter down too far as you'll notice it on the end result,as soon as it's slow enough you'll see the flicker go,Mark

Posted by Alex Wilson (Member # 6247) on January 08, 2018, 04:28 PM:

Thanks Mark, is there a benchmark as to where to start... 100??? 60?? Higher or lower the Sony can be adjusted in increments of 10..

Aw.

Posted by Janice Glesser (Member # 2758) on January 08, 2018, 05:00 PM:

I'm more familiar with Canon camcorders....but if possible...Set your shutter speed to 60fps for NTSC or 50fps for PAL and increase the projector speed to about 20fps for NTSC or 15 for PAL or until flicker or banding is minimized or eliminated. If you still get some flicker at 60/50fps try 30/25fps.

Posted by Paul Adsett (Member # 25) on January 08, 2018, 05:03 PM:

The shutter speed on my Sony camera just goes from 1 (normal) to 4 (slow). I found that setting at 2 pretty well eliminates flicker. I think the trick is to just slow the shutter enough to minimize flicker. If you slow the shutter too much you will get motion blur.

Posted by Alex Wilson (Member # 6247) on January 10, 2018, 12:44 PM:

for a screen board to play 8mm film on....flat or glossy ? [Confused]

Posted by Mark Mander (Member # 340) on January 10, 2018, 12:47 PM:

Whatever looks better for you Alex,I prefer flat as I think glossy reflects the light back on the camera,Mark

Posted by Alex Wilson (Member # 6247) on January 10, 2018, 12:53 PM:

I was thinking the same... flat it will be.

Posted by Jim Cowell (Member # 6272) on January 13, 2018, 09:09 PM:

Another newbie here. One reason I joined was to try to find out how to eliminate the flicker of Super 8 footage when transferred to video. I use a Panasonic GH5, but it produced marked banding and flickering when I pointed it at my Super 8 film projected on to a translucent screen. It was a fixed-speed projector, and I thought I was going to have to modify it somehow, maybe by replacing the motor. Big job, and daunting.

But then I was told on another forum that the GH5 has a feature called "synchro scan", that allows you to adjust the shutter speed/fps rate in small increments. I set it to run at 24.1 fps, and the flicker disappeared completely! Hope this will help someone else.

I still joined up anyway, because this forum looks like a great source of information, plus a good place to talk to like-minded folks.

Jim.

[Smile]

Posted by Janice Glesser (Member # 2758) on January 13, 2018, 10:02 PM:

Welcome Jim...glad to have you on board [Smile]

Posted by Jim Cowell (Member # 6272) on January 13, 2018, 10:32 PM:

Thanks, Janice. I'm glad to be here. [Smile]

Posted by Nantawat Kittiwarakul (Member # 6050) on January 15, 2018, 01:39 AM:

Most super 8 projector would have a fixed 3-blade shutter which will give a 54Hz "flicker" (18*3=54,simple as that). This number won't play well with most camcorders since this is not the EXACT multiples of video's frame rate.There're some possible options to tackle this.

1.Speed up the projector to 20 fps.The resultant output flicker would be 20*3=60Hz,exactly matches the NTSC's 60i rate. This should also work for 30p frame rate too.

2.If you happened to have to use your camcorder at 24p frame rate,it might be necessary to modify the projector to use 4-blade shutter instead.It will give 18*4=72Hz output,exact multiples of 24p hence no flicker whatsoever.The only issue is if it's possible to modify/replace the shutter blade. Would be fairly simple in certain models,and totally impossible in other models. [Roll Eyes]

3.Better yet,slowing down the projector to 16 fps the output will be then 16*3=48Hz,also the exact multiples of 24p too.But this might be a serious issue for some sound film due to the lowered audio pitch. (And might be unnoticeable in some case,too)

4.Or use a camcorder with variable shutter speed (aka"synchro scan"). Dialing the shutter down to 1/54s,the flicker bar should be disappeared then.There might be some give or take depending to the exact projector's speed.

Fortunately I'm living in a PAL land where things are pretty easier to handle. I merely run the silent film at 16.67fps,resulting in 16.67*3=50Hz. Running sound film at 25fps will give 25*3=75Hz. All are exact multiples of PAL frame rate,no flicker problem then. [Big Grin]

Posted by Jim Cowell (Member # 6272) on January 16, 2018, 04:34 AM:

quote:
4.Or use a camcorder with variable shutter speed (aka"synchro scan"). Dialing the shutter down to 1/54s,the flicker bar should be disappeared then.There might be some give or take depending to the exact projector's speed.

Yes, that was the option I chose, Nantawat. As soon as I discovered that I had that option, that is! Must read my camera manual more thoroughly in future... [Big Grin]

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