Silent films expressing sound?!

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71er
Posts: 217
Joined: Wed Dec 31, 2008 7:59 am
Location: Austria

Silent films expressing sound?!

Post by 71er » Sat Jan 10, 2009 10:44 pm

Watching the film of the link http://www.magyar.film.hu/object.f54367 ... 43875d.ivy, which is given in the thread "home movies", without sound brought me to the point where a dog barks and at the same moment the film is overexposed. First I thought it was on purpose to express sound visually but I had to find out that those moments of overexposure are not related to what is happening in the scenes.
I have never seen anything like it, but it should be possible to show noise and certain sounds by visual effects like the one described above. Has anyone ever tried this or do you know a film that experimented with it? I find the thought of it quite fascinating.
Alex
Alex

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bwat
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Joined: Mon Dec 29, 2008 1:57 am

Re: Silent films expressing sound?!

Post by bwat » Sun Jan 11, 2009 2:09 pm

Sounds like you're describing a kind of cine-synaesthesia. I suppose we could take a camera with automatic exposure and insert a microphone into the exposure feedback circuit so that different levels of sound would dampen or amplify the signal sent to the motor which turns the aperture ring.

At my feet I've got more resistors, pots, op amps, and microcontrollers than I know what to do with. If I only had a disposable camera I would give it a shot.

You're right, it does sound interesting.

71er
Posts: 217
Joined: Wed Dec 31, 2008 7:59 am
Location: Austria

Re: Silent films expressing sound?!

Post by 71er » Sun Jan 11, 2009 4:05 pm

I actually do have a few Zeiss Ikon Moviflex at home; I bought them from ebay, did simple repairs to them and after testing with film I want to sell them on again. If you want I could send you a Moviflex S8 for this project. I also own a copy of the repair manual, which includes the electronic plan of the camera. I am not very good in electronics so I could not make the alteration myself but I can see that those cameras have a comparatively simple layout.
Are you interested? Do you have time for this?
I guess in the end only sudden short sounds would be interesting as a constant high background noise would just lead to constant overexposure; I am thinking of fast passing objects (starting planes, ambulance, trains), machinery that makes a hammering noise, animals with sudden sound expressions (like the angry dog), etc.
Where are you situated?
Alex

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bwat
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Joined: Mon Dec 29, 2008 1:57 am

Re: Silent films expressing sound?!

Post by bwat » Tue Jan 13, 2009 1:56 am

I'm writing this in Sweden 71er.

With regards to background noise it would all be a matter of configuring the circuit so that only the deviations from the background noise would lead to a deviation in exposure. One would configure background noise just as one configures film speed. I'm imagining a variable resistor the user would manipulate to match the background noise before starting to record images.

I'm beginning to worry about how quickly the motor controlling the iris ring would react to sudden changes in sound. A quick deviation from the norm would probably lead to a small change in exposure which would quickly return to normal. A more prolonged deviation (train, machinery, etc.) would give a definate change in exposure for roughly the extent of that deviation. I guess this is what you described above?

Does the repair manual have a electrical diagramme? If I can figure out how the feedback circuit is designed in that camera model I can maybe build a small prototype here to see if the whole idea is feasible.

71er
Posts: 217
Joined: Wed Dec 31, 2008 7:59 am
Location: Austria

Re: Silent films expressing sound?!

Post by 71er » Tue Jan 13, 2009 12:47 pm

Yes, you are right, the iris motor is to slow to react fast enough to sudden short sounds - you would get the overexposure too late and not matching the picture, or not at all. So with this type of camera you could only do longer lasting loud sounds.
I also have two Eumig standard 8 cameras and they don't have an iris motor (I haven't taken them apart but the aperture changes without having batteries in); I guess the iris is moved by a coil, which gets its current from a Selenium cell - is this possible? This reacts much faster than the Moviflex iris motor. I don't have such a camera available for tests but today there is one on ebay ... I'll have a go.
As the Eumig has a separate inlet for the light meter you would only have to hang a lamp in front of the inlet which gets brighter when the sound goes up. Very simple for first experiments to start with ...
I have got the electrical diagramme for the Moviflex as well. What's your preference to try?
Alex

Keep on Movieing!

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