KAM Laserscan 3D ILDA Laser

[musicologydisco]

You'll get plenty of mixed views. Some think the low power lasers we dj's use aren't a big issue. Others err on the side of extreme caution.
There are still no reports of people being affected by lasers despite decades of crowd scanning (except the odd very silly exception) so to me that speaks volumes. It's up to you to make your own judgement really. I'm happy to crowd scan as it is a big crowd pleaser and no one has ever complained or expressed concern. Give em what they want and let the rest wring their hands is what I say!

[chrisj]

If you don't care about Health and Safety and peoples eyesight it is up to you. Your choice but 3b laser is dangerous. I always advise clients of this and say if I use the 3b laser it will be above eye level as even if the beam passing the eye swiftly enters the eye it can burn the retina but the person will not know as there are no nerves in the retina.
I will also mention that my sister-in-law is a specialist nurse in the Eye Clinic at the Norfolk & Norwich Hospital and backs me on this.

Class IIIb lasers are intermediate power (c.w. 5-500 mW or pulsed 10 J/cm²) devices. Some examples of Class IIIb laser uses are spectrometry, stereolithography, and entertainment light shows. Direct viewing of the Class IIIb laser beam is hazardous to the eye and diffuse reflections of the beam can also be hazardous to the eye. Do not view the Class IIIb laser beam directly. Do not view a Class IIIb laser beam with telescopic devices; this amplifies the problem. Whenever occupying a laser controlled area, wear the proper eye protection. Refer to the University of Kentucky Laser Safety Manual for complete instructions on the safety requirements for Class IIIb laser use.

[Solitaire Events Ltd]

My advice is to listen to professionals, not DJs who use them as toys.

I'm happy to crowd scan as it is a big crowd pleaser and no one has ever complained or expressed concern.

Oh, that's alright then.....

[Corabar Entertainment]

Nobody has ever voiced concern to me about carrying a gun at discos.... maybe I should start arming the DJs

[Chris1984]

You'll get plenty of mixed views. Some think the low power lasers we dj's use aren't a big issue. Others err on the side of extreme caution.
There are still no reports of people being affected by lasers despite decades of crowd scanning (except the odd very silly exception) so to me that speaks volumes. It's up to you to make your own judgement really. I'm happy to crowd scan as it is a big crowd pleaser and no one has ever complained or expressed concern. Give em what they want and let the rest wring their hands is what I say!

Despite me saying i wasn't going to comment on this anymore i feel i have to.

Your attitude towards laser safety and lack of knowledge is exactly what is wrong with the laser industry and is not acceptable.
You clearly dont understand what you are doing and despite being given advise buy a professional laser operator and several others you ignore it and carry on regardless.

You cant scan the audience in the UK full stop - i have said this and you have picked it apart with copy and paste from a website who trains people like myself to operate lasers all over the world where rules are different wherever you go.
Im in Australia at the moment and the rules of what we can do change from state to state.
If you speak to any reputable laser company (there are are couple in the UK) then im sure they will also say they wont do it and it isnt worth the risk with our current H&S rules.

The fact you feel you have to to give a good show also emphasis you dont know how to use a laser and im going to guess you use it on sound to light mode.... A proper laser show dosnt need to scan the crowd to wow them.

If you feel you have to scan the crowd then how can you prove its below mpe and how can you prove you can shut the laser down immediately if there is a problem and how can you guarantee the effects into the audience are suitable.
the answers are you can't as you dont have a meter or have the background understanding how to use one, you will be concentrating on the music not keeping a beedy eye on the laser which you will not be infront of anyway so will struggle to see a problem untill to late and dont have an estop anyway and you have it on sound to light mode so can't control what the out put is.

It would seem your a 30 quid sid of the laser industry.

And despite you saying no one has been hurt so its fine - you are yet again wrong and many people every year are burned with lasers at events and just because you havent heard about this or using your search engine hasnt found any cases to fit what your doing dosnt mean its not a real problem that is happening with cowboy operators scanning crowd across the globe.
We dont have many laser burn problems in the uk as up untill now lasers have been to expensive and we dont audience scan in the uk, but now people are buy cheap lasers there are problems and oit is becoming more and more of an issue.

I really dont understand you issue with hat im saying, if i needed dj advice i would ask on here and listen to dj's if i was ill i would seek the advice of a dr yet you seem to feel to be an expert of lasers despite me trying to help. As i say i may not be a dj anymore but i travle the globe with artists, bands and groups doing lasers in front of millions of people and have a vague understanding on whats involved in the task.

choose to listen or not, i dont mind but if you scan the audience with your attitude please expect some comebacks.

[chrisj]

Well said. The majority of the public have no idea that the lasers can be dangerous to the eyes. I visited the longest barn in the country 2 weeks ago to see the venue and meet the function co-ordinator as well as my clients for their wedding. The couple said they would like the UK Laser Rainbow Vision, 425mw, that I use but had earlier mentioned a doorway up stairs at the far end of the barn would be used by several of their guests throughout the evening. Approximately 60 mtrs away from my laser if I were to use it. I could direct the beams well up towards the roof but some would probably be low enough to hit people at the far end so I have said for H&S reasons I will not use it. If there is a safe way to use it I will do so but at the distance of 60 mtrs the spread is very very wide in all directions. Better be safe than sorry.

Many times I have explained the harm that a lot of lasers can cause as people just do not know, they trust the DJ who is operating it.

[Jem]

Hi all

I've stayed out of this thread up to this point because I get tired of trying to 'convert' people to err on the side of caution when using lasers. Chris has given some good advice here and you should listen to him.

I'd like to throw a couple of figures into the mix... Let's assume that you're using a 100mW laser with a beam divergence of 1mRad. How far away from the beam do you reckon you'd need to be for it to not cause an ocular hazard? 10 meters? 25 meters? 50 meters?... Well no, the answer is actually 71 meters or 232.2 feet. At this distance the beam spot size would be 73mm. Therefore the size of the beam has increased to such a level (& therefore the irradiance of the beam would have reduced) that only a small part of it enters the pupil thus rendering the beam safe.

Now, how many people on here use 100mW lasers?, and how many people are using their projector at a distance of 71 meters from their audience? Ahh, not many I guess. These aren't figures just plucked out of the air they are facts. O.K., so the given example is a basic calculation as there's much more to calculating a MPE (maximum permissable exposure) that that simple example given above. To do the job properly you have to know Power, wavelength, divergence, beam diameter at the aperture of the projector, and also you need to know the duration of the exposure (a whole seperate area when using scanned effects). You'll need a fast silicon diode photodetector, an oscilloscope and a scientific calculator and a few other bits and bobs. Plus you'll also need to know the exact specifications of each laser in your projector to do the job properly.

You see, the problem is that if you're using lasers to scan the audience and there's an incident that ends up in court you won't have a leg to stand on. How can you possibly file a successful defence in the abscence of calculations? If you've done the calculations and can prove your show was safe you'll have a much better chance of defending yourself. Incidentally, you'll have a very hard job proving your show was safe if you're using a Chinese laser, as the vast majority of them don't have scan fail devices, E-Stop buttons etc etc. If you choose to ignore the advice given, well, that's up to you. But believe me HSE are becoming much more aware of the influx of cheap lasers flooding the UK market. For your own protection may I respectfully suggest that you keep all beams well above the audiences heads unless you can prove competence in calculating MPE's and have the documentation to prove your show is safe.

Using good control software (NOT DMX!) such as 'Pangolin' (http://www.pangolin.com) you can control the show and programme Beam Attenuation Mapping (BAM's) to reduce the power of the beam below the horizon. Then there are special lenses that can be placed in front of the projector aperture as to increase the divergence of the beams thus rendering them safe at closer distances. Pangolin sell such an item called a SafetyScan lens http://www.youtube.com/watch?feature...&v=ooZ1C5gL7FA. However, yet again, you will need to know how to use them. It's all about reducing risk, and just because you haven't heard of the incidents doesn't mean that they aren't occurring...

When I was doing professional lasershows I had a huge H & S policy (Risk assessment and method statement) for each individual show that I did. This contained lots of information about the specifics of the show and I had conclusive proof that the shows were safe. This included calculations for any audience scanning that took place. If you're even thinking of scanning an audience you should be doing the same.

Now, having said all that, it's up to you what you do, but ignore the advice at your (eventual) peril.

Kind Regards, and thanks for listening

Jem

[musicologydisco]

I would avoid lasers that only scan with stepper motors as the beam will move a lot slower than with galvos. Also do some research on the internet. I've now been slated for putting sections from official websites for some reason but, hey, at least I've managed to back up some of what I've said!

[Jem]

Please don't feel 'slated', that really isn't the intention here. Well, it certainly wasn't my intention anyway. I am more coming from the angle of trying to gently 'educate'

By presenting some facts and figures I was hoping that you would see the problems for yourself. Also, don't forget that I have nothing to gain here, but anyone who audience scans in ignorance stands to potentially lose everything. All it takes is one person with the backing of a 'no win no fee' lawyer to say their eyes were damaged at your show and you're going to struggle to defend yourself without proper documentation.

Best policy is to get them beams up high and leave 'em there unless you really know what you're doing

[musicologydisco]

Wasn't getting at you at all. Yours was a much better, and informative post. A question for you...the measurement of safe distance for 100mw laser. Is that for a single static beam? There seems to be plenty of info for this kind of laser emission but a lack of solid facts about scanned beams. It seems that there is fear of risk more rather than fast scanned beams actually being a proven problem. At least from what I have managed to find out by looking at sites like ILDA's.
Also, do you know of any prohibition of audience scanning in the uk like the other guy said. Or indeed of many injuries sustained through crowd scanning? I'd really like to see some evidence of this perceived problem (not the german pulsed laser incident from years ago which is a daft example). Cheers