Laser beams and mirror balls

[steve h]

I would like to point out somethine I said earlier.

 

The effect given was very similar to that of hitting a small facet mirror ball with a bright green lights. Yes it is slightly tighter ande brighter but you may save yourself a lot of effort by going a more conventional route!

 

Steve

[tom_the_LD]

I was playing for a production of Return To The Forbidden Planet which had a laser hitting a mirror ball - it certainly wasn't a "point" laser but one which emitted a line (|) and it looked eally nice through the haze. I'll try and find out which laser was used.

 

Another option, depending on the rig. IF you have movers (I'm not saying get some), it can look quite nice to have a rotating dichroic gobo on the mirror ball - I've seen this trick used a lot in panto and I quite like it. I have even used it myself before!

 

Here are some examples:

http://i167.photobucket.com/albums/u121/tom_the_drummer/Diamond%20Wedding%20Anniversary/P1000081.jpg

http://i167.photobucket.com/albums/u121/tom_the_drummer/Diamond%20Wedding%20Anniversary/P1000080.jpg

 

E2A: Of course if you don't have movers in the show, then a S4 with gobo rotator and nice dichroic will do just as great job!

[mrjammy83]

I have used profiles hitting a mirror ball so many times and we all know the effect so was intruiged to know what a laser would achieve.

 

I personally feel Laser light produces a beam very difficult to replicate well with Generic fixtures. there is something powerful about the beam that pierces through the air as opposed to generics that bounce off the particals in the air. its this Force and power I wish to convey during the transformation of the beast.

 

Also Laser light appears not to Illuminate objects it touches etc ( it does but you get my drift in comparison to generics)

 

ooooh get me going all gushy

 

I must say its is more the Laser beam effect I would prefere to that of a mirrorball. An effect that has the audience captured other than that "oooh the trusty mirrorballs out again. (ita a panto fave)

[musht]

Have to insert this at this point in the discussion ;-)

 

http://www.electricstuff.co.uk/scarylaser.gif

 

If you really want to go in depth into the subject , http://www.photonlexicon.com/forums/forum.php is the place to ask.

 

The basic idea is anything above 5mW, 5/1000ths Watt, has the possibility to damage your eye before blink or aversion reflex kicks in.

 

Below 5mW dmage is theoretically possible but yout likely to blink first.

 

Its getting the desired effect bright enough, which with low power laser means setting the preceding scenes low enough that the laser appears bright.

[tomrbland]

So far from this thread I have gathered. NO its not possible. YES it is possible (heres a picture). and DON'T use a laser or someone will die.

 

....

 

Take PLASA for instance. Lasers pointing Every which way and even moving head ones. (how do you ensure noone will look at a beam from a moving head laser!!! IS THE BIGGEST RISK FROM THE SOURCE OF THE LASER OR THE BEAM ITSELF

 

E2A: Just found this video. So do we all Duck and run or look in amazement. laser ball

 

I would just like to add another voice to MrJammy83's points of Laser safety. When ever anyone mentions lasers they get bombarded by people putting the LD off using them. Lasers are a fantastic tool in lighting design and often give 'that something special' to a performance. IMO use of lasers shouldn't be discouraged but SAFE use of lasers should be encouraged. We have heard many people say no don't do it but not many saying "yes do it, it would be great, but make sure you abide by HSE...... and such and such guideline... oh and some safety tips I found really useful are..."

 

I have seen lasers used on mirror balls to great effect. I must disagree to it looking just like a mirror ball with a generic fixture: the beam is much narrower and finer, the colour is much more vivid (in the case of reds you don't need silly amounts of power just to make the effect work)

 

My vote on the topic is this: if that is the effect you want, don't let rules and regulations stop you doing it. Usually with these things someone will have the relevant system worked out to carry out the checks necessary - it's just a matter of finding that person. I'm sure there are various laser hire companies out there that would offer advice (the reputation of lasers is in their interest - they want more people to be using lasers as it gets them more work!).

 

On the point of PLASA

is a good example.

[The Seedage]

It is worth getting to know what you can and cant do with lasers, especially when talking about 'low powered' or 'cheap' lasers..

 

Yes the effect is possible, and yes, even in a small scale situation, there are safety issues, but on a simple one off effect, with the right controlls, you can achieve the effect that you want.

 

What I would advise against, is looking towards the 'disco' end of the market. A little insight into the systems that you can pickup around the 100mW-500mW mark off ebay or several reputable companies - I got hold of a cheap £300 400mW laser so I could rob the diode out of the system for lining up our 5W, 10W and 40W system optic tables roughly before putting the bad boys on them.. What I found after metering the output, and calculating the beam size in accordance with the guidelines, is that these low powered lasers are more dangerous than the big boys!!

 

The beams tend to be very tight, with low divergence, which when doing precision stuff is great, but you dont want to be taking a hit in the eye with them. I calculated that in the absence of any scan fail protection devices (which sense issues with the scanning mirrors and cut the beam off within a safe reaction time), that audience scanning with these lasers couldnt be justified unless the audience were over 60m away from the head... Added to this that the control boards really drive the galvos (mirrors) to the max from factory settings (which in my opinion over continued use, will lead them to an early demise), and you really cant justify it on safety grounds..

 

Now, take a look at all those people who have these lasers in mobile disco situations... Just because its cheap and not above 500mW doesnt mean its not dangerous!

 

On the positive side, if you can get a decent control on the system, and make the pattern on the mirrorball both axis (I normally find that an ellipse shape tumbling or folding on an angle), and with enough distance between laser and mirrorball, and masking the audience to make sure they cant access emmisions above the MPE, with suitable briefing of staff, and relevant controls to E-Stop, you should be able to do it! There is also a free demo of the software that works with the majority of the green DPSS lasers that run at 532nm, so you can even provide the calculations to back up your theory.

 

PM if you need more advice..

[paulears]

Most of these pictures seem to show lasers with diverging beams - I thought this was the one thing lasers didn't do?

[Brian]

Most of these pictures seem to show lasers with diverging beams - I thought this was the one thing lasers didn't do?

They do if you stick a lens in front.

[mrjammy83]

There it is

 

The last 2-3 post (plus the warning sign) are finally undeniably helpful and Posistive for what I wish to achieve.

 

my first instinct was, like anyone working for amdram. budget kit= savings. however from seedage's ss (too many esesses) post I now reminded "you get what you pay for".

 

Tomrblands post has enligtened me to WHAT I BLOOMING DIDN'T SEE AT PLASA and also that If I were to get my hands on one of them it would create the perfect effect I require while we all watch the mirrorball roll down the street. Amazing video.

 

So It seems the blueroom** needs more "training" on what can and can't be done with lasers and the safety implications of there use.

 

So my questions continue.

 

If I were to hire a laser (to create the mesmorising effects similar to the Plasa video above.) how much would it cost?

 

How do you go about programming these things?

 

are there specific venue sizes they suit? etc

 

I have more but I'll stop for now...

 

** by blueroom I mean the threads and info concerning Lasers etc for searchable future reference.

 

 

E2A: Mods feel free to adjust the topic title and description to better cater for the advance in the topics information.

[The Seedage]

I may be corrected here (as I only dipped into the demo at PLASA), but the video is basically a lot of mirrors/prisms inside a cube, reflecting 2 x whitelight solid state lasers (looking at it, around the 1w mark).. The effect being it looks like a lot more lasers!!

 

Venue wise, it all really depends on what you want to do..

 

(Editing is a bit choppy, but you get the idea)

In this place, the audience is only around 20m away from the effects head (which houses a 4w Purelight Argon/Krypton laser). The beam effects are coming off a fixed beam table (rather than scanning mirrors), and so precision is more stable (precaution 1!). The lasers themselves look really close to the guy and the cast, but they are actually going up to the roof, bouncing down back onto the top of the set, then out to a mirrorball (or to another bounce mirror). The calculations prove that even at 4w, by the time you've bounced 10m to the top of the venue, back another 10, then 20 to the audience, taking into consideration the loss of beam quality, the precision of the hits, and the final end position of the beams (which in the real world were at the safe distance about the audience, but sat in the stalls, it felt a lot closer, that the effect is pretty safe. Add onto that, E-Stops to take out the laser both backstage and the control tower (show actually run on timecode, so operator basically is a lookout for any issues), and the risk assessment is fairly comprehensive.

 

If you youtube a few more from that show (Forbidden, Blackpool Pleasure Beach), you'll see a few more effects that are close to cast, but again scanning speeds are up in the 30kHz spectrum, and the system has scan fail on both main table and fibre optic table, so safety is assured.

 

All within a small venue with a medium powered (for indoor stuff anyway) laser.

 

Programming wise, a lot of the lasers on the market at the moment come with a cheap DMX board that basically do preset patterns.. Again, not a fan after my experiences with my cheapo system, as they tend to be quite erratic and output wide to drive the scanners a bit more than I would like. Best way is get a dedicated laser controller so you have total control. I'm a fan of the old Laser Innovations controllers (but they are like rocking horse crap, and I'm just a little bit biased - those who know me know why!!!), but there are loads out there (Pangolin, PM21 Merlin etc). Smoothest effects for cones/lines are the ones that use oscillators rather than graphics to create the shapes, but most allow both...

 

Price wise is a difficult one.. People like me have moved away from lasers apart from installed ones (like the one on the link above), as the ebay market drives people to buy their own and be dangerous (on the whole)... Why should people pay for the experience, when they can get an entire system for the same price of day rate on a laser safety officer/operator?? In reality, a 'real' laser costs thousands to buy and even more to run safely once you've done calcs, documents, site visits etc.. Looking into over 1k per day on proper rental at the very least.. My gas systems have stayed mainly on the shelves except for long term installs, and the occasional fireworks, but the DPSS system has gone out fairly constantly (but only with me at the healm)

 

Again, get what you pay for... Bet that a 200 quid a nite display with a £400 laser wont come with a full risk assessment, caclulations or probably even any kind of emergency planning!!

 

I could rant for ages if this was a disco forum!

 

There it is

 

The last 2-3 post (plus the warning sign) are finally undeniably helpful and Posistive for what I wish to achieve.

 

my first instinct was, like anyone working for amdram. budget kit= savings. however from seedage's ss (too many esesses) post I now reminded "you get what you pay for".

 

Tomrblands post has enligtened me to WHAT I BLOOMING DIDN'T SEE AT PLASA and also that If I were to get my hands on one of them it would create the perfect effect I require while we all watch the mirrorball roll down the street. Amazing video.

 

So It seems the blueroom** needs more "training" on what can and can't be done with lasers and the safety implications of there use.

 

So my questions continue.

 

If I were to hire a laser (to create the mesmorising effects similar to the Plasa video above.) how much would it cost?

 

How do you go about programming these things?

 

are there specific venue sizes they suit? etc

 

I have more but I'll stop for now...

 

** by blueroom I mean the threads and info concerning Lasers etc for searchable future reference.

 

 

E2A: Mods feel free to adjust the topic title and description to better cater for the advance in the topics information.

[ImagineerTom]

Ok, laserbeams look like lasers; they don't look like anything else and the public can recognise them instantly, if you use lasers I promise you most of your audience will be thinking "oooh look clever lasers" - it won't be in the slightest bit magical and will actually distract from the story at the one moment when it really shouldn't. The transformation scene in BATB should have the audience on the edge of their seat with their heart in their mouths, it should be full of texture and wonder with the audience wrapped up in the emotion of the moment; NOT thinking "ohh what cool disco lasers" - magic is /organic/ not crisp and sharp.

 

I've worked on a lot of BATB productions (from original disney to panto, ballet, theme park, the full gamut) and can tell you that LESS is more when it comes to lighting effects during this sequence - the most successful and spectacular transformations I've done have used a handful of led bulbs, a bit of smoke and knowledge of exactly how to push the audience's emotional buttons. I've also been brought in to rescue far too many ridiculous over-engineered solutions with lasers, clouds of smoke and mountains of technology that just destroy the magic of the moment.

 

If you must use light beams behind the transformation then use something filament based at 50% power (soft warm glowing beams look like magic) an old disco moonflower bastardised will do the job a lot better than lasers and mirror-balls but you must also go right back to the drawing board and think very carefully about what this sequence actually NEEDS.

[Dmills]

Agreed, I always wince when (Wearing my laserist hat) I get asked to put lasers into a theatrical context, there are a tiny number of productions where it can be appropriate, mostly of the 'Forbidden planet' or 'WWRY' type, but for the rest it tends to be telling that when you ask the director what effect they are actually trying for they almost never seem to know!

 

Telling the tech what gear to use as opposed to what you want the effect to look like is generally a bad idea unless you KNOW that the gear will do it.

 

I had someone asking about life size, MOVING! holograms the other day, because lasers can do that (Apparently (I think not!)).... Turns out that simple video projection onto a few carefully setup screens will get them everything they actually need, but they wanted the technology to be cool (Gah!).

 

Maybe I am just getting old and cynical, but nine times out of ten when the director turns up with a request for big technology that they don't really understand it is because they have run out of ideas or the actor is not up to snuff and they think that SHINY! will be a suitable substitute for a meaningful performance.

 

Regards, Dan.

[mrjammy83]

WOW More constructive posts. first blueroom thread in ages thats gone anywhere constructive.

 

 

ANYWAY

 

seedage. you certainly know your stuff and judging by those estimate prices it way out of my budget

 

imagineerTom. you couldnt be more right and thinking about the scene in the film, its very sublte and gentle when the beast transforms. with subdued colours and sparkle. (I have been basing the use of lasers on one moment at the very start of the transformation which at the going rate for a laser would be like rigging a flying system for peterpan to then walk across the stage. (OTT and pointless). luckily I'm still very much at the drawing board phase and the blueroom allows me to hammer out these very sort of ideas sensibly before commiting to anything. Aswell as learning a thing or two onn the way for future reference.

 

I have to admit that much of my lighting work had been mainly with generics with colour and gobos etc to suit and when I have used movers I always makesure its subtly done so as not to detract and as has been said I think thats just what a laser would do.

 

Dmills. I myself have commented on posts on here regarding folk that want to play with the shiny stuff and would advise on the contrary 9 times out of 10. however this sort of kit is out there to be used and in its perfect setting makes for a fantastic effect.

 

After every ones lengthy, helpful and very constructive post I and hopefully many others have something to go on when they undertake a design process and head down the same path as I. Lucky for me it early days and I can turn back and go a different way.

 

Thanks everyone for your suggestions and comments. I will be back with some more seemingly wise and wonderful ideas soon no doubt.

 

Keep up the good postings

 

James

[sleah]

What systems are in place to stop say a Mobile dj buying a laser projector and riggingit on his kit. with it scanning and spreading points of light all over a crowded hall. the laser cluster fixtures do just that.

Come on guys. Lasers are now easily purchased from any disco shop. (these are the sort of thing I'm looking to use. nothing too big) surely the H&S post above are extreme for that.

 

Nope, nothing in place other than the knowledge that ignorance is no defence in law. The H&S posts are not extreme, you need to know!

 

Please don't think that quote regs and telling you not to go mad are having a go or being negative. It would be the same if you posted that you wanted to use a gun on stage and do we think borrowing a starting pistol from the PE dept would work.

 

Before anyone (well most on here!) will tell you that using a laser is a good idea or will look great, they want to know that you understand all the implications, be it doing RA's, knowing how to rig and operate to actually appreciating the potential damage that can be caused.

Once that's out of the way...... let the creative juices flow

[ANDYLASER]

Rather than aiming a single beam at a mirror ball, a far better effect can be created by using a rotating flat scan, or a pulsed circle. This will also provide more movement to the effect and produces a lower power density to reflected beams.