8mm Forum: Elmo 16 CL ETC Ghosting at top of frame

This is topic Elmo 16 CL ETC Ghosting at top of frame in forum 16mm Forum at 8mm Forum.

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Posted by Max McCarty (Member # 2606) on October 30, 2019, 01:30 PM:

Many years ago I picked up a used Elmo 16-CL ETC24 to do film transfers. The motor would squeal and the projector would jump whenever I tried to use it, so I put it on the shelf and forgot about it. The other transfer projector I use (a Telex) was having some issues, so I decided to dig out the old Elmo and see if I could fix it. Turns out it just need a set screw on the main drive pulley. Once I replaced that it works great! The only problem I'm still having is that on some films there will be a little ghosting in light areas at the top of the frame. If there are no light areas, you can't really see any ghosting. Is this the shutter claw or a matter of timing the shutter? Thanks!

Posted by Janice Glesser (Member # 2758) on October 30, 2019, 03:11 PM:

Hi Max and welcome to the forum. I'm not sure what you mean by ghosting at the top of the frame. Ghosting usualy occurs through out the entire frame when the camera captures combined frames as the film moves thru the gate. This creates a super imposed trailing image captured by the camera. If you are only getting ghosting at the top then try adjusting the framer to see if that helps. I tried for a very long time to eliminate the ghosting using my Elmo 16CL 3 blade and 5 blade shutters when transferring 16fps films. No dice. If the film is 24fps and your camera is set for 24fps there shouldn't be any ghosting or at least only minimal with a 3-blade or 5 blade shutter. After a lot of research mathematically for 16fps films it would take a 4 blade shutter to fix the ghosting. I ended up going with a frame by frame projector which did the trick.

You can read about it in this thread:

http://8mmforum.film-tech.com/cgi-bin/ubb/ultimatebb.cgi?ubb=get_topic;f=5;t=001763

[ October 30, 2019, 07:02 PM: Message edited by: Janice Glesser ]

Posted by Nantawat Kittiwarakul (Member # 6050) on October 30, 2019, 08:09 PM:

That's possible that the shutter timing is only off by a fraction, making it barely noticeable.
If it's mechanically the same as standard 16-CL, there will be just 2 grub screws locking the shutter pulley to the main shaft. Loosening it a bit and nudge it down a millimeter or two would help (yes, it's that critical). [Roll Eyes]

Posted by Maurice Leakey (Member # 916) on October 31, 2019, 03:59 AM:

Ghosting is often caused by the shutter not being in timing with the claw, it needs to be either advanced or retarded.
It's wise to remember BRAT in these circumstances.
Below Retard, Advance Top.

Posted by Janice Glesser (Member # 2758) on October 31, 2019, 02:07 PM:

Max can I assume you are telecining by recording the realtime projected image with your video camera? Also... is the film you are trying to telecine 16fps or 24fps? If it's 16fps even if your shutter timing is perfect you will still get ghosting in the recorded image. Maybe you could clearify. What settings are you using on you camcorder?

Posted by Max McCarty (Member # 2606) on October 31, 2019, 02:08 PM:

Many thanks for all help. I tested this film on a standard Elmo 16-CL and didn't see the problem. My transfer projector is an Elmo 24 ETC that has the synchronous motor and tooth belt to keep the speed constant. I'm using it with a Buhl bi-plexer to convert to digital. With all my 8mm Elmo ETC projectors the video camera is set at 30 frames per second (1080i 30P). My video capture camera is a Panasonic HPX170 with a variable frame rate. Just for fun, I set the frame rate to 1080i 24P. The ghosting effect disappears! I'm not sure why this works, but for now I'm happy it does.

Posted by Janice Glesser (Member # 2758) on October 31, 2019, 02:43 PM:

Max...what is the framerate of the film you are transferring?

Posted by Max McCarty (Member # 2606) on October 31, 2019, 02:59 PM:

The film is 24 fps. It's the same frame rate as the video camera, but I thought with the special 5 bladed shutter, the projector was designed to be used with video cameras set to 30 frames per second.

Posted by Janice Glesser (Member # 2758) on October 31, 2019, 07:13 PM:

OK Max...then yes you are fine. With film at 24fps and your camera at 24fps you will not get ghosting. It's only on old silent 16fps home movie films you can eliminate flicker...but not the ghosting with realtime capture.

Posted by Nantawat Kittiwarakul (Member # 6050) on October 31, 2019, 08:12 PM:

Ah...that sounds fun to me. Let's do a math. [Wink]

- Assuming that both projector&camcorder runs at (more or less) the same 24 fps. Not a perfect sync, but darn close.
- The projector is 5-blade, so the frequency is 24*5=120 Hz.
- Then set the camcorder to 24p mode, shutter speed 1/120 sec and voila, flicker-free&almost frame-accurate transfer. [Big Grin]

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