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Author Topic: Flicker help
Alex Wilson
Junior
Posts: 17
From: Burlington, ON, Canada
Registered: Dec 2017


 - posted January 08, 2018 02:55 PM      Profile for Alex Wilson   Email Alex Wilson   Send New Private Message       Edit/Delete Post 
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..

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Alex

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Paul Adsett
Film God

Posts: 5003
From: USA
Registered: Jun 2003


 - posted January 08, 2018 03:06 PM      Profile for Paul Adsett     Send New Private Message       Edit/Delete Post 
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.

--------------------
The best of all worlds- 8mm, super 8mm, 9.5mm, and HD Digital Projection,
Elmo GS1200 f1.0 2-blade
Eumig S938 Stereo f1.0 Ektar
Panasonic PT-AE4000U digital pj

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Alex Wilson
Junior
Posts: 17
From: Burlington, ON, Canada
Registered: Dec 2017


 - posted January 08, 2018 03:49 PM      Profile for Alex Wilson   Email Alex Wilson   Send New Private Message       Edit/Delete Post 
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.

--------------------
Alex

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Mark Mander
Phenomenal Film Handler

Posts: 1236
From: Dunstable ,Bedfordshire.
Registered: Jan 2005


 - posted January 08, 2018 04:12 PM      Profile for Mark Mander     Send New Private Message       Edit/Delete Post 
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

--------------------
Elmo GS1200 1.0 lens
Elmo ST1200HD 1.1 lens
Sankyo 800 1.0 lens
Elmo 16CL
Elf NT1

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Alex Wilson
Junior
Posts: 17
From: Burlington, ON, Canada
Registered: Dec 2017


 - posted January 08, 2018 04:28 PM      Profile for Alex Wilson   Email Alex Wilson   Send New Private Message       Edit/Delete Post 
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.

--------------------
Alex

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Janice Glesser
Film Goddess

Posts: 3468
From: Sunnyvale, CA USA
Registered: Sep 2011


 - posted January 08, 2018 05:00 PM      Profile for Janice Glesser     Send New Private Message       Edit/Delete Post 
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.

--------------------
Janice

"I'm having a very good day!"
Richard Dreyfuss - Let It Ride (1989).

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Paul Adsett
Film God

Posts: 5003
From: USA
Registered: Jun 2003


 - posted January 08, 2018 05:03 PM      Profile for Paul Adsett     Send New Private Message       Edit/Delete Post 
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.

--------------------
The best of all worlds- 8mm, super 8mm, 9.5mm, and HD Digital Projection,
Elmo GS1200 f1.0 2-blade
Eumig S938 Stereo f1.0 Ektar
Panasonic PT-AE4000U digital pj

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Alex Wilson
Junior
Posts: 17
From: Burlington, ON, Canada
Registered: Dec 2017


 - posted January 10, 2018 12:44 PM      Profile for Alex Wilson   Email Alex Wilson   Send New Private Message       Edit/Delete Post 
for a screen board to play 8mm film on....flat or glossy ? [Confused]

--------------------
Alex

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Mark Mander
Phenomenal Film Handler

Posts: 1236
From: Dunstable ,Bedfordshire.
Registered: Jan 2005


 - posted January 10, 2018 12:47 PM      Profile for Mark Mander     Send New Private Message       Edit/Delete Post 
Whatever looks better for you Alex,I prefer flat as I think glossy reflects the light back on the camera,Mark

--------------------
Elmo GS1200 1.0 lens
Elmo ST1200HD 1.1 lens
Sankyo 800 1.0 lens
Elmo 16CL
Elf NT1

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Alex Wilson
Junior
Posts: 17
From: Burlington, ON, Canada
Registered: Dec 2017


 - posted January 10, 2018 12:53 PM      Profile for Alex Wilson   Email Alex Wilson   Send New Private Message       Edit/Delete Post 
I was thinking the same... flat it will be.

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Alex

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Jim Cowell
Junior
Posts: 10
From: Brisbane, Australia
Registered: Jan 2018


 - posted January 13, 2018 09:09 PM      Profile for Jim Cowell   Email Jim Cowell   Send New Private Message       Edit/Delete Post 
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]

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Janice Glesser
Film Goddess

Posts: 3468
From: Sunnyvale, CA USA
Registered: Sep 2011


 - posted January 13, 2018 10:02 PM      Profile for Janice Glesser     Send New Private Message       Edit/Delete Post 
Welcome Jim...glad to have you on board [Smile]

--------------------
Janice

"I'm having a very good day!"
Richard Dreyfuss - Let It Ride (1989).

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Jim Cowell
Junior
Posts: 10
From: Brisbane, Australia
Registered: Jan 2018


 - posted January 13, 2018 10:32 PM      Profile for Jim Cowell   Email Jim Cowell   Send New Private Message       Edit/Delete Post 
Thanks, Janice. I'm glad to be here. [Smile]

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Nantawat Kittiwarakul
Master Film Handler

Posts: 280
From: Rajburana, Bangkok, Thailand
Registered: Aug 2017


 - posted January 15, 2018 01:39 AM      Profile for Nantawat Kittiwarakul   Email Nantawat Kittiwarakul   Send New Private Message       Edit/Delete Post 
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]

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Just a lone collector from a faraway land...

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Jim Cowell
Junior
Posts: 10
From: Brisbane, Australia
Registered: Jan 2018


 - posted January 16, 2018 04:34 AM      Profile for Jim Cowell   Email Jim Cowell   Send New Private Message       Edit/Delete Post 
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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