Author
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Topic: WHY THE DIFFERENCE (in speed) ??
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David Pannell
Phenomenal Film Handler
Posts: 1072
From: Horsham, West Sussex, UK
Registered: Nov 2004
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posted July 27, 2005 12:27 AM
Purely out of interest, does anybody know why silent speed for Standard 8 is 16fps and Super 8 is 18fps? - and why dual standard projectors only have the 18fps speed setting?
Being the pedantic engineer that I am - (a bit like having all the correct boxes for everything, I guess!) - if I shoot at 16fps, I want to project at 16fps, and likewise for 18fps.
It's not actually an issue for me, because I can use my Elmo E-80 for 16fps projection and of course the ST1200 HD for 18fps. However, my recently acquired Eumig 810D, (which is primarily intended for Standard 8 sound anyway, 24fps) will only do the 18fps thing on the slow speed setting. If I switch the frequency control to 60Hz, it runs at 14fps.
I should like to have the option of using the Eumig running at the correct speed and I wonder if it's possible to alter the cam on the speed switch to give the desired 16fps, or whether to experiment by putting a few ohms in series with the motor to slow it up a bit for the 16fps setting. Has anyone tried either of these ideas?
I know that probably 2fps is nothing to worry about, but it's just this 'thing' of having everything right. I would just add that in a previous thread, I spoke about a stroboscope which I use for calibrating my cameras and projectors, so I know exactly at what speed things are running.
Cheers,
Dave.
-------------------- Dave.
Valves and celluloid - a great combination! Early technology rules OK!
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Paul Adsett
Film God
Posts: 5003
From: USA
Registered: Jun 2003
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posted July 28, 2005 10:54 AM
Hi Dave, Many Reg 8mm film cameras had a continously wariable film speed capability. For instance the Bolex C8/B8/D8 cameras all had a calibrated speed selector knob which could be set anywhere from 8fps to 64fps(for slow motion) with calibration marks at 8,12, 16, 24, 32, 48 and 64 fps. I think the Bell and Howell "Sportster/ Viceroy" cameras also had similar facilities. You could easily set these cameras at 18fps because there was calibration marks for 16 and 24 fps, so it was easy to estimate where the 18fps position would be. Later versions of the Bolex's had a red 18fps setting mark. What sweet cameras those little 8mm wind-up Bolex's were. I still have mine (a C8 with impressive Pan-Cinor zoom lens), and everytime I pick it up the quality of design and finish just amazes me.
-------------------- 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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