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Strange Camera Artifacts

Cyparagon

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I notice these in my ancient camera when taking a video of an argon spyrograph tunnel a few years back. I haven't seen them anywhere else until now in Jupiter8's avatar:



Does anyone else see things like these regularly or know what causes them? The beam is shifted in the exposure, but I don't see how the exposure could shift faster than a beam of light. It seems to stop, and reappear elsewhere in the frame. Here are some shots from my old video









 

jupiter8

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Re: Strage Camera Artifacts

Yep I know what causes it cyparagon. The frame rate for the camera (frames per second) is almost in sync with the revolutions of you mirror, which the laser beam is bouncing off, or scanning rate if it's a scanner. So what you see as dark areas, missing or blank areas, is where the laser is tracking somewhere else at the time the camera shutter is open. It's the same as the scrolling horizontal lines you see sometimes when you film a TV screen with a camcorder, and the scan rate of the TV almost matches the frame rate of your camcorder. I liked how it looked, despite being an artifact, so I used the picture as an avatar. Cheating I know!
 

Cyparagon

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Re: Strage Camera Artifacts

But it's the same for every speed of the mirrors.

Edit: I could understand if it was split radially, but it's cut off mid-beam. I don't think exposure can be faster than the speed of light.
 
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Gryphon

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Mishap or not those look sweet! I really like the second to last one :drool:
 

Cyparagon

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Oh they're not a hassle, I've got plenty of other cameras I can borrow. I was just curious as to what caused them.
 
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I have that in my spiro videos, it bugs me. check my sig for a link, it's in the picture link at the very bottom.
 
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It's not a blu-ray, it's a 473. Its only 5mw so it's not near as bright as the others and it's pulsed so that probably helps to negate the effect, but you can still see it a bit.
 
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Yes, I love it too but my stupid fog machine broke a few months ago and haven't been able to do anything like that for a while. :(
 
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Mine was left on overnight(not by me), just heating till it got to fogging temp. and cooling then reheating and cooling...etc, for around 18 hours. now it doesn't heat up any more. The light comes on, but it's done. NOTHING. argh!
 




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