Laserman532 7 Watt White Light Projector Circa 1990

[dsli_jon]

Yeah I was almost positive the accuracy for bounce mirrors would become the major challenge.

Thats what I figured, but if you use dichros wouldn't you be limited to only that one color per turret?

I look forward to seeing it

I think you mis-read me! haha,

Hey Max -

RE: Beam tables vs galvos - yeah, and range of motion - study the pix of Pats' work-of-art, there - I am sure you can imagine / visualize the HUGE 'range of motion' - well, maybe more correct to say 'range of POSITIONING' but I'm sure you get the point..

RE: dichros, well yes, IF you were ONLY sending a non-color-modded beam down the 'rail' - IF you had an additional color-control (like the 'color-box', seen below) you COULD, with specific wavelength or 'angle-tuned' dichros, introduce some interesting color variations from the same positions...

RE: beam-table operation anime - still looking for it, but I think, from this color-box anime (IMAGE COURTESY of and © LMR, Laserfx.com ) you can likely imagine / visualize it - imagine these dichros are, at angles, reflecting ONE line (color) from the WL beam to one position (MM1, out to the 'house' or bounce mirror, etc) and passing another line (color) to a second - or to 3 or 4 more - gets pretty cool, pretty fast!

RE: beams vs gratings - LOL - yeah, I think we were both on 'late-nite' frequencies, there my original comment was not about gratings at all, but BEAMS I think BEAM-work (like from these types of table-projectors) is underapreciated by a lot of - certainly not all - PL-ers, just cause I don't see a lot, if any, of these types of projectors being built / worked on, by many of the 'nu skoolers' around here.... anyhoo you get it!

Talk to ya soon...
- J

[mliptack]

Heh yeah I get it, I knew you were talking about beams but you also mentioned machito gratings and such...

Are you at all familiar with moving lights? Particularly the Vari-Lite series of fixtures? In a situation like the image above illustrates, something like the dichroic wheel in the newer VL fixtures would be a great option. Just much smaller. In addition to that flag system you posted. The resultant combo would be a fast color changing system that would be able to change to any color in a short frame of time.... just not as fast as a PCAOM or Analog modulation...

[DZ]

RE: beam-table operation anime - still looking for it, but I think, from this color-box anime (IMAGE COURTESY of and © LMR, Laserfx.com ) you can likely imagine / visualize it - imagine these dichros are, at angles, reflecting ONE line (color) from the WL beam to one position (MM1, out to the 'house' or bounce mirror, etc) and passing another line (color) to a second - or to 3 or 4 more - gets pretty cool, pretty fast!

I don't have a photo or video of this in action, but here's an old photo from a previous projector I had. I had not aligned them properly when I took this photo, but its close and you get the idea.

[Laserman532]

i just sold three of these mounts for gm20 with shutters on ebay last week they went for 1.00 ea.. you guys need to watch my auctions!

[Laserman532]

woops forgot the link

http://cgi.ebay.com/ws/eBayISAPI.dll...MESO:IT&ih=004

[Banthai]

Hi Pat ....

I am now fitting some GM 20s into my new projector to be used as beam diversion and shutters ..... is there a prefered method of driving them ? ... position is not critical ..... can i simply drive them direct from a 12V supply with a limmiting resistor in series ?

any help much apreciated ...

All the best .. Karl

[Laserman532]

Someone correct me if necessary, to my knowledge you need something better to drive them so that they can be damped because of the mass you could get ringing of the long arm Unless you dont care about sequencing speed. We had a circuit card that would drive 8 gm-20's an i am pretty sure you will need a bit more sophistication. If you are just using them for a shutter your plan might work...expensive shutter tho. jon will know for sure.

[dsli_jon]

I am now fitting some GM 20s into my new projector to be used as beam diversion and shutters ..... is there a prefered method of driving them ? ... position is not critical ..... can i simply drive them direct from a 12V supply with a limmiting resistor in series ?

All the best .. Karl

Hey Karl! - yeah, like Pat said, depends on your app - if you are just using it for a shutter / perhaps 1-2 'occasionally up' fx, like a machita or lumia, etc, but for multiple actuators, we usually use this bad boy http://www.lsione.com/1602adrv.htm cause for hi-speed 'picking' you really do need the damping and offset -

Really, I know you already have your GMs and are not looking to spend more bux, but for just a simple, TTL-direct-drive shutter or 1-2 fx actuation, the STP-8x's are fine - MUCH less expensive, and a good deal smaller footprint, for 'space challenged' projectors... - unless you really need FAST actuation, or 'fading', I'd save the GM20s for another project, ie: http://www.photonlexicon.com/forums/...1&d=1200645693

'HoloSpectra', here in the States, sell these, and also, a lower-cost, non-DMX driver board - 'read all about it' at http://www.lasershs.com/laser_optical_actuator.htm and you can email Bill Arkin, there, for details - over on 'your side of the pond' MediaLas sells em http://www.medialas.de/showlaser/kom...optomech_e.htm so I am sure your good buddy Dirk can 'hook ya up with all the 411' -

One last one, is there are these Japanese 'GM20 clones', (see pic below) that, like the STPs, have driver electronics built in, so it's just 12V to power, and 3-5V to actuate, but they are 'tighter' and 'snappier' like the GM20s... I think PL-Member 'One Stop Laser Shop' MAY still sell them (OSLS) - they're not bad, and like only about $85., if memory serves...

Hope this helps - PM for more info!

Cheers! -
-J

[Banthai]

Thanks Guys ....

im using 1 as the main safety shutter and the other to divert the beam to a Poly20 grating wheel so no fast speed required

I will look at the STPs though ... im sure mark ( fluff had some for sale recently ) ....

thanks for this interesting thread .... so im gonna jump out of it now and let you continue your journey

all the best ... Karl

[VJ AIWAZ]

the stp 8 is not suitable as a safety shutter as it lacks a return spring
its a stepper so when its not energized it will not hold a position and could just stay any where it stops

--
John
VJ AIWAZ