8mm Forum: Projector with 25fps

This is topic Projector with 25fps in forum 16mm Forum at 8mm Forum.

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Posted by Luigi Castellitto (Member # 3759) on October 27, 2017, 01:52 PM:

A Meopta "Meoclub" 16mm projectors series have 18 and 25fps, instead of standard of 24fps.
I don't know why Meopta made this choice, but this could affect the viewing of mute films and films with optical and magnetic audio? And of amateur movies shot at 24 fps? And with rec feature of some Meopta?
25fps is it influential on image or sound? In some demonstration videos on Youtube it seems all right.
Thank you.

Posted by Maurice Leakey (Member # 916) on October 27, 2017, 02:47 PM:

My engineer tells me that most 16mm Bell & Howells run at 25fps.
The slightly faster speed is probably not discernible by the ears.

Posted by Brian Fretwell (Member # 4302) on October 28, 2017, 05:48 AM:

Well that would explain where there wasn't much, if any flicker on my home telecine attempts with a PAL video camcorder and a B&H 2692.

Posted by Luigi Castellitto (Member # 3759) on October 28, 2017, 11:58 AM:

Ah, I did not know about Bell & Howell.
If I have a Meopta, I will also make amateur telecinema tests.

Posted by Dominique De Bast (Member # 3798) on October 28, 2017, 07:27 PM:

Many projectors (all the "récent" ones) have a 18 fps speed instead of the classical 16 fps. Some allow to project also at 16 fps but you have to change a pulley. That's a problem with convertef (to 9.5) projectors as many amateur films were shot and sonorized at 16 fps. Unfortunately, the difference, at these slower speeds is noticeable.

Posted by Maurice Leakey (Member # 916) on October 29, 2017, 03:17 AM:

A good point made by Dominique, particularly in regard to home movies originally shot at 16fps.

Posted by Luigi Castellitto (Member # 3759) on October 29, 2017, 05:44 PM:

True also the point of 16/18.
And even then, there is no difference of audio and image.

Posted by Dominique De Bast (Member # 3798) on October 30, 2017, 02:12 AM:

There is,Luigi. The people will walk faster on the screen at 18 fps than at 16 fps. The sound will also be altered.

Posted by Luigi Castellitto (Member # 3759) on November 07, 2017, 05:24 PM:

True, Dom. Now I have a Meopta Meoclub 16 Electronic 2, I can make a "speed" test.

For my Meopta model experts: the projector doesn't have the motor belt, which I have already found at Wittner and co..
Do you confirm that it has two belts+motor belt? The other two belts have "teeth". In my projector there are only other two belts, but in good condition.

Another question: I also have to change the lamp for optic sound. In Electronic "1" version manual says Philips 2 7253 C o Atlas G 29, cheap and fortunately found. In Electronic 2 manual says only 4v 0,75 A, but I think the two lamp models are always good, what do you say?

Thank you.

[ November 07, 2017, 06:26 PM: Message edited by: Luigi Castellitto ]

Posted by Nantawat Kittiwarakul (Member # 6050) on November 07, 2017, 10:46 PM:

(Probably off-topic reply,but hey...)

The older projectors with governer speed-controlled universal motor will give the option to "fine-tune" the speed. I managed to set my Elmo 16-f projector to be EXACTLY 25.0 FPS for my telecine setup. Completely flicker-free in PAL video speed. [Smile]

But for Super 8 transfer there must be quite a compromise - at 18 fps you'll sure get moderate flickering. Gotta run it at 16.67(50/3)fps to be flicker-free,which will lower the audio pitch somewhat. But since ALL costomers never complain/notice,so I won't bother to correct this "issue". [Big Grin]

Posted by Luigi Castellitto (Member # 3759) on November 13, 2017, 09:03 AM:

The projector arrived, I had to change the motor belt and excited lamp, but now it's all Ok, except magnetic audio that not works (maybe I open another post).

With movies films with optical audio all fine with 25fps, I did not notice any differences in picture and speed [Smile]

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