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Don't you think it's dangerous to look into some of these high power video projectors? If there is a danger to the audience, who will protect the public if it's out of the CDRH jurisdiction? This could be opening a big can of worms. What if you video scan the audience with a video projector that incorporates lasers? Couldn't the CDRH step in?
No more so than looking into the projection lamp at the movie theater, to say nothing about the "blinder" series strobe lights that are used at rock concerts these days. (Or what about the famous "Sharpie" moving head DMX fixtures?)Quote:
Originally Posted by Photonbeam
It's extremely unlikely that you will cause permanent retina damage by looking at a bright non-coherent light source, because your natural pain / aversion response should force you to blink / look away in less than a second. (The standard figure normally quoted for blink response is .25 seconds) Then too, the spot will not be focused to a diffraction-limited spot as a laser would be.
For a real-world example - How many times have you caught a "flash" of sunlight off the chrome bumper of the car in front of you? Did it ever cause permanent eye damage? No, because you either blinked or looked away almost immediately. (Because it hurts!)
Sure, you *CAN* cause damage if you force yourself to look at these lights for long periods of time (and somehow manage to withstand the considerable pain it will cause), but is that something that needs to be regulated? After all, I can cause serious damage to my head by hitting it repeatedly with a hammer, but no one is seriously suggesting we regulate hammers to protect people's heads, are they?
Lasers, on the other hand, are capable of causing permanent damage BEFORE you have a chance to blink. That's why they are more dangerous, and why they are regulated.
Granted, I think the MPE for laser exposure here in the US is ridiculously low, but that's not to say that I don't agree with the concept in general.
As stated above, I don't believe there is a danger. Bright lights have been a part of stage shows since the late 1960's, and I can't say that I've ever read anything suggesting that they are causing permanent eye damage.Quote:
If there is a danger to the audience, who will protect the public if it's out of the CDRH jurisdiction?
Then too, most modern DMX moving heads that are designed for commercial use are far brighter than the DLP projectors we're discussing here. Furthermore, as I mentioned above, commercial strobe lights are STUPID bright when compared to even the largest Barco and Christie projectors.
If you have evidence to suggest that non-coherent lighting is causing permanent eye damage to the general public, I'd be very interested to read it.
If you're referring to the Ca$io-style DLP projector that uses 445 nm diodes for blue (and indirectly, to generate green), then the answer is still no, because those projectors do not output collimated light. The beams from the laser diodes are passed through a filter which breaks up the light and destroys the coherence.Quote:
What if you video scan the audience with a video projector that incorporates lasers? Couldn't the CDRH step in?
This is why you don't need a variance to own or operate one of these Ca$io projectors. It's expected that someone could reasonably walk in front of a video projector and be illuminated, so it has to be eye-safe.
I don't remember the specific classification that the Casio projector received, but I'm pretty sure it's on-par with DVD drives. (That is, no coherent exposure outside the box, regardless of what levels exist inside the unit where no eyeballs can ever go.) Though admittedly Casio still had to file a product report on it to get that classification.
Adam
Those are all good points. Thanks Adam!
Quote:
Originally Posted by buffo
Hey thanks!,
Ive got to try this ASAP..
pretty much got everything i need to try it out .
Can I try this without having Beyond? How about a beam show (in 2D) exported from LD2000 as an .avi file and played back with my C@$i0 projector?
I am going to try this today. This will be awesome if it works like that video.
Can multiple projectors be used, each displaying different content?
I am trying to set this up now.. with no luck. I added the projector under laser and emulaser controller hardware. Then went into projector settings and confirmed it was there. It wont show a test pattern. I even went into projection zones and set it up.
If I hit the alt F5 then the projector just projects the desktop, like it supposed to. But for some reason beyond wont project out the port for anything :( ... any ideas?
Think I figured it out. You have to enable 2 screens on computer. Then set the projector to be full screen on the second screen. Then anything you project there shows. I am about to fire up my hazer and see how it looks. My projector is super bright but.. atleast I can give it a basic test.
I did not actually watch to see how Aaron set it up. I'll try and look at it when I get home from work. Maybe someone else can chime in during the interim.
Stiffler - I would guess if you had multiple video cards, it would be possible but again, this is going to be a learning exercise for all of us.