I need a smoke machine

[Jem]

Yes please Jem. £20 you say...

Yes, £20 it is... Must be a nice clean crisp note though

Cheers

Jem

[laserLips]

haha, oh well I'll get the Iron out ... all my notes seemed to be rolled into tubes

[buffo]

To expand on what Jem mentioned, you can also mix 635 nm with 660 nm using a custom dichro. This is an ideal solution if you've already got a pair of Maxyz modules combined with a PBS cube and you still need more red.

Unfortunately, the one source I've found for the dichros in question wants me to order a minimum of ten of them at nearly $100 a piece. I'm still looking for a cheaper source for a dichro that will reflect 660 nm and pass 635 nm. (Or vice versa...)

The other combination method that Jem mentioned is based on the Arctos design, where you have multiple identical diodes and you use the knife-edge of a mirror to position each beam very close to the next one. Unfortunately, this still results in a larger-diameter beam.

Adam

[laserLips]

Adam... I took note of what you said ages ago about this dichro and have been looking for one myself...I saw this http://cgi.ebay.co.uk/ws/eBayISAPI.d...TODAY.m238.lVI

and didnt read it properly and baought it....its no good though for this is it...

Plonker...anyway why cant I just shove 635 and 660 through one fo those cubes I got from Bridge? I guess losses?

Graham

[Jem]

you can also mix 635 nm with 660 nm using a custom dichro. This is an ideal solution if you've already got a pair of Maxyz modules combined with a PBS cube and you still need more red.

Adam

Please correct me if i'm wrong here but adding 635 to a pair of 660's won't result in increased power will it? It'll give you a better colour gamut from the mix of wavelengths but I thought that you were only able to mix 1 x H Pol and 1 x V Pol into the same beam. I was under the impression that the only other way was going down the Arctos route.

I guess you could mix a 635 and a 660 if both were opposite polarisation, and you had a beamsplitter cube with the correct coatings - correct?

Please educate me

Cheers

Jem

[mliptack]

There is the quad maxyz thats being developed but isn't available yet

Also you might want to talk to Adam, he was thinkign about organizing a group buy for dichros for passing 635 and reflecting 650 which would be nice for combining a Maxyz with another laser. The catch a minimum qty of 10 @ $100 a piece.

-Max

[buffo]

Graham;

Yeah, what you bought there is basically an IR filter, only in reverse. It's a dichro that passes 1064 nm while reflecting 632.8 (and, presumably, 635 as well). But it won't work to combine 635 and 660. Sorry.

Jem;

You are correct in that you can only use a polarizing beam-splitting cube to combine a pair of beams once. (This is because the resulting output beam will have random polarization. If you try to send it through a second PBS cube, half of the beam will be rejected by the face.)

However, I was not talking about using a PBS cube to mix 635 nm with 660 nm. Rather, I was suggesting the use of a custom dichroic mirror (like we normally use to mix red, green, and blue laser light in our projectors) to combine a 660 nm beam with a 635 nm beam. Such a mirror would pass the 635 nm light from that diode while reflecting the 660 nm beam coming from the PBS cube.

The problem with this approach is that 635 nm is very close to 660 nm. So you need a custom dichro that has *very* narrow tolerances for reflection and transmission. This drives up the cost of the dichro, and indeed, the one I was able to find that would do the job would have cost $100 each in quantities of 10 or more. (As Max posted above.)

Now, if you only have one 660 nm laser and one 635 nm laser, you *can* use a PBS cube to combine them. This is a lot cheaper than buying a custom dichro. But if you already have a pair of Maxyz modules in your projector that are combined with a PBS cube (as many members here do), then you're sort of stuck. You can't easily add more red, unless you adopt the Arctos method of positioning multiple beams close together, and we all know how messy that gets...

But if you instead decide to add red at a different wavelength, you can always use a dichro to accomplish the mixing. (Well, within the limits of the dichro's optical coatings, that is... It would be very difficult to build a dichro that would reflect 635 nm while transmitting 632.8 nm, for example. But it could be done.) This way you can add some 635 nm red to your existing 660 nm red. This gives you a lot more total red (because 635 nm appears much brighter than 660 nm), while preserving most of your color range (because you still have the deep 660 nm red present). It's a great solution, except for the cost of the dichro and the added complexity in the projector's optical path.

Adam

[carmangary]

Has anyone tried making the hazer out of the coffee urn heater like on the laser fx page? It seems a little unsafe but I'm dying to know how well it really works.

[buffo]

Nah, I saw that one but never had the balls to try it. (And with halloween foggers selling for $24.99 at Walmart, there's really no need to try.)

Tell you what though, I have been tempted to try loading up some fog juice into an ultrasonic vaporizer to see if that makes a fine haze or not.

Adam

[Smeisner]

If you want a hazer I can recommend an Antari Z-300. It uses normal smoke mashine liquid and is not that expensive. On eBay they goes for around $250. I got a used one for 125,-


...and, yes - I'm new here at PL, but have spent lots of hours already, reading old posts.

/Steen