Illuminate Your Video Inspections with a 30/60Hz Strobe Lamp

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For effective video inspections in large scenes with limited power, using a strobe light triggered at 30Hz or 60Hz can provide bright illumination synchronized with the camera's frame pulse. The efficiency of pulsed lighting compared to continuous illumination is debated, with considerations on the imaging array's readout duty cycle playing a crucial role. Interline transfer CCDs allow for rapid image transfer, potentially improving power efficiency per pixel when using strobe lighting. However, consistent illumination is necessary to avoid dark bands in the final image, especially with scanning cameras. Exploring options like attaching a photo flash unit to the camera may enhance overall efficiency in capturing images.
mgb_phys
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I need to illuminate a scene for a video inspection.
Unfortunately it's a big scene and I don't have unlimited power.

I though of using a strobe light triggered at 30Hz (or ideally 60Hz) and synced from the frame pulse of the video camera - so I get a bright pulse of light as each image is taken.

Anyone know of a strobe that can do 30/60Hz rate?
 
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I'm not sure a strobe of comparable power to continuous illumination will be any more efficient. The imaging array is integrating the incident radiation (I think), so whether it is continuous or pulsed shouldn't make much of a difference.

I guess I'd need to research how the latest imaging arrays are read out, though. If the readout duty cycle isn't real narrow, then you could pick up some efficiency, probably ratioed to that duty cycle.
 
It's an interline transfer CCD, so I thought if I ran a strobe at 30Hz and only recorded one field I at least got a 2x improvement in power/pixel.
Worse case I can slow it down even more and throw away more fields.

The problem is that the camera is scanning over a scene, but I can't move the illumination so I'm stuck with trying to illuminate everything while building up an overall view of the scene.
 
You may be reading the sensors in short bursts but they need to integrate the received energy over a reasonable time and I think that even digital image arrays are scanned - so you will need illumination all the time or you will get dark bands on your TV picture.
 
CMOS arrays are scanned, especially on slow frame rate webcams.
Interline CCDs transfer the current image almost instantly (few us) to the storage register and read it out while integrating the next field.
 
Can you maybe charge up a flash unit, and periodically shoot a flash picture that is sync'ed to the scan of the camera? It sounds like you are going to store and process the images anyway, so maybe just having a series of flash frames will work? How quickly is the camera scanning? Could you attach a photo flash unit to the camera body, so you get that increase in efficiency as well?

BTW, I just read your footer -- killing me here...

Irony = it's like goldy or silvery but made of iron
 
berkeman said:
BTW, I just read your footer -- killing me here...
I had one warning about irony, but some people seemed to still need an explanation

Not original though
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