An "Easy-Pan" Camera?

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An "Easy-Pan" Camera?

Postby ac7zl » Wed Apr 18, 2007 9:39 am

Hello All:

Pretty much all of the mechanical camera and televisor designs I've seen so far, whether disk or mirror based, involve rotating parts on a horizontal axis.

In the case of a static camera, this probably isn't of much consequence. However, gyroscopic forces being what they are, I would imagine that transient problems with speed control/synch might arise if one tried to pan the camera too abruptly.

I can think of two work-arounds. The first would be to install a hinged mirror at the lens to the camera. The idea is that, rather than pan the camera, we pan the mirror.

Another idea involves changing the mechanics to rotate about a vertical axis. Suitable mirrors and lenses would be required to translate the image appropriately. I've attached a crude drawing demonstrating the idea.

I thought I'd toss this out to the forum. Any thoughts?

Pete
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Panning concept.

Postby Stephen » Wed Apr 18, 2007 10:58 am

I like it! Especially with a larger disc that results in a large camera enclosure this would be more convenient. I assume that the mirror an its associated lens would mount on a swivel base.
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Re: An "Easy-Pan" Camera?

Postby Roland » Wed Apr 18, 2007 11:17 am

ac7zl wrote:Another idea involves changing the mechanics to rotate about a vertical axis. Suitable mirrors and lenses would be required to translate the image appropriately. I've attached a crude drawing demonstrating the idea.

I thought I'd toss this out to the forum. Any thoughts?

Pete
AC7ZL


I've not built a camera - but I have built a monitor with the disk arranged like this. The only real problem was that I mounted the motor directly on the baseboard leaving insufficient room for the lightsource.

Anyway - in principle I think its a great idea and you can get a nice optical mirror for it by breaking open an old Polaroid camera (anything that uses integral film (not the peel apart type) has a front surface mirror in it).

:-)

Roland.
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Postby Viewmaster » Wed Apr 18, 2007 6:41 pm

Because of the low definition on NBTV I would have thought that fast panning was out anyway.
NBTV is a slow, old sedate way of viewing surely not suitable for the fast panning techniques used in film and modern TV?
I wonder if the old Baird NBTV ever had pans, fast or otherwise?
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Postby Klaas Robers » Thu Apr 19, 2007 3:02 am

Yes, they had. Because they had just ONE camera, no cuts and fades from one camera to the other were possible. But they had a mirrordrum flying spot projector, which projected a moving light spot onto the scene in a dark studio. However the arc lightsource gave quite some light. In stead of lighting armatures photo detectors were hanging from the ceiling. In fact the light direction was inverse to that of a camera.

With this projector (mirror drum with horizontal spindle) they could pan, but not tilt. Tilting was simulated by moving a cadre before the projector up and down. Of course then the picture in the monitors also moved up and down and hopefully the rotating disc found the framing again after some time.

This is also the problem with the horizontal rotating disc camera. If you do a pan, then is the synchronisation rate influenced. This might make monitor synchronisation unstable.
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