Hello,
   I've only had a moment to skim your code, but you will need photons 
to be able to have the light do anything after it reflects.  I was 
messing with something very similar a while back and wrote something 
about it here that might help.  Basically I needed to end up bumping up 
my photons media parameter (though yours is probably plenty high, just 
enable it) and really increasing the media samples.

Here's the message:
http://news.povray.org/web.47af1f65c0351d35b05f96f70%40news.povray.org
There's some other good suggestions in the rest of the thread as well.

This is the scene file when I finally got it working:
http://news.povray.org/web.47af219494e592ceb05f96f70%40news.povray.org

and the corresponding image:
http://news.povray.org/web.47af23af94e592ceb05f96f70%40news.povray.org

Hope its helpful.

-- 
-The Mildly Infamous Blue Herring

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"You may not post attachments to this newsgroup."
Apparently Jim can.

somewhat humorous


I will post to images "for Jim"

Let me know if you see anything you want info on.

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"alphaQuad" <alp### [at] earthlinknet> wrote in message 
news:web.4880bb89f15fb2b65083b53c0@news.povray.org...
> "You may not post attachments to this newsgroup."

no even if it's part of the discussion? (sign sign everywhere a sign) also 
somewhat humorous

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Jim Holsenback nous illumina en ce 2008-07-18 10:28 -->
> "Reactor" <rea### [at] hotmailcom> wrote in message 
> news:web.487f9f80f15fb2b6210497120@news.povray.org...
>> Povray can do this, but I would like to see your code so we can figure out 
>> why
>> it isn't.
>>
>> -Reactor
> 
> Ok ..... here's the source file photons commented out. Don't need that just 
> yet right?
No! You absolutely NEED to turn photons on now. Without photons on, there is no 
reflection of the beam.
> 
> I've attached a reference image. Notice I can see the target in the 
Please don't post image here, it's not a binaries group.
Instead, include a reference to a similarly named post on povray.binaries.images

> reflective object .... also the reflection of the beam from the source. 
> That's not the beam bending but it's reflection. I also commented out the 
> optical device as I don't need that yet either. One change I made was the 
You effectifely don't need any visible object emiting your light.
> intensity of the looks_like light source ..... it WAS a color vector * 1000 
> ..... I just bumped up the intensity of the scattering media to make up for 
> lowering the intensity of the emitter light source. Orginally the light beam 
> hitting the target produced an almost white-ish look (highly saturated) 
> ..... a laser beam should leave a red (or light source) colored point of 
> light .... correct?
A laser can be any colour, from far infrared to hard UV. IR and UV are 
invisible. A UV laser can cause the air to turn fluoressent and emit light, and 
that light can have several colours, and apears white if the beam is strong enough.
Visible laser are 100% saturated, monochromatic lights. So, just make sure that 
at least one component is set to zero.
> 
> Thanks
> Jim
> ---
> 
> global_settings {
>   max_trace_level 10
>   /*photons {
>     count 100000
>     autostop 0
>     media 1000
>     max_trace_level 10
>     }*/
>   }
Uncomment that photons block. Otherwise, the beam will never get reflected.
> 
> background {rgb 0.125}
> 
> #declare Camera =  <15,1.5,2.5>;
> 
> camera { location Camera look_at <0,0,2.5>}
> 
> // makes the lightsource visable
> box {<100,100,100>,<-100,0,-100>
>   hollow on
>   pigment {rgbt 1}
>   //photons {pass_through}
>   interior {
>     media {
>       intervals 1
>       samples 1 //5,25
Need more samples. Use 100 or possibly more.
>       confidence 1 - 1/1000
>       variance 1/1000
>       ratio 0.9
>       scattering {
>         1, color rgb 10
>         extinction 0.0
>         }
>       method 3
>       aa_threshold 0.1
>       aa_level 4
You don't need that much, aa_level 2 or 3 should be enough.
>       density {color rgb <1,1,1>}
>       }
>     }
>   }
> 
> // reflector yellow border
> union {
>   box {<-2.5,-0.1,-2.5>, <2.5,0.1,2.5>
>     pigment{rgb 1}
>     finish{ ambient 0 diffuse 0 reflection 1}
>     }
>   box {<-2.6,0,-2.6>, <2.6,0,2.6>
>     pigment{rgb <1,1,0>}
>     finish{ ambient 0.5}
>     }
>   rotate z*90
>   rotate y*315
>   //photons {target reflection on refraction on}
>   }
Uncomment this. This is required for the photons to work.
> 
> // recptor blue border
> union {
>   box {<-0.1,-1.5,2.5>, <0.1,1.5,-2.5>
>     pigment {
>       onion scale 0.5
>       color_map {
>         [0.0 rgb 1]
>         [0.35 rgb 1]
>         [0.35 rgb 0.1]
>         [1.0 rgb 0.1]
>         }
>       }
>     finish{ ambient 0.5 diffuse 0.5 reflection 0 }
>     }
>   box {<0,-1.6,2.6>, <0,1.6,-2.6> pigment {rgb <0,0,4>}}
>   rotate y*90
>   //photons {target reflection on refraction on}
Not needed.
>   translate <0,0,5>
>   }
> 
> // optic device
> /*sphere  {
>   0, 0.5
>   pigment{ color rgbt <1,1,1,.95> }
>   hollow on
>   finish{ ambient 0 diffuse 0 reflection .5  }
>   interior{  ior 1.5  }
>   //photons {target reflection on refraction on}
>   scale <0.01,1,1>
>   translate <2.5,0,0>
>   }*/
> 
> // the emitter
> light_source {
>   <0,0,0>
>   color rgb <1.0000, 0.2900,0.2000>
Make it: color rgb<10,0,0> if you want a red laser.
For a laser, at least one colour component MUST be zero.
>   cylinder
For a laser, you should also add parallel.
>   tightness 0
>   radius .025
>   falloff .025
>   point_at <-1,0,0>
>   fade_distance 500
You don't need light fading in this case as the fading of laser is negligeable 
at human scale.
>   fade_power 2
>   /*photons {
>     reflection on
>     refraction off
>     }*/
Optional. Thise are on by default for any light_source.
>   looks_like {cylinder{0,<0.1,0,0>,0.1 pigment {rgb <4,0,0>}}}
>   translate <5,0,0>
>   } 
> 
> 
> 


-- 
Alain
-------------------------------------------------
You know you've been raytracing too long when you look at a matrix transform and 
know instantly what it does.
John VanSickle

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"Alain" <ele### [at] netscapenet> wrote in message 
news:4880dff4$1@news.povray.org...
> No! You absolutely NEED to turn photons on now. Without photons on, there 
> is no reflection of the beam.

danke .....

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here's one to check out

adapt Blue Herrin's code like,

#declare reflector =
box {
  <-0.5, -4, -4>, <0, 4, 4>
  hollow
  pigment { rgbft <0,1,0,.1,.9> } //White }
  finish {
    reflection { 1 }
  }
  photons {
    target
    reflection on
    refraction on
  }
  rotate z * 45
  translate x * -9
}
object { reflector }


in place of current reflector, I dont know why I am see what I am seeing.
3 beams reflected and transmitted? well I really cant see it yet, very slow.

render center region with drag, low low res

next logical step experiment with prism shape , perhaps other shapes

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light source went from red to green, i forgot to say


light_source {
  x * 30, Green * 10
  cylinder
  point_at x * 24
  radius 0.1
  falloff 0.5
  tightness 0.25
  photons {
    reflection on
    refraction on
  }
}


and I am looking straight on


camera {
  location <0, 0, -25>
  up y
  right x * image_width/image_height
  look_at 0
  translate x * -9
}

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alphaQuad nous illumina en ce 2008-07-18 16:54 -->
> here's one to check out
> 
> adapt Blue Herrin's code like,
> 
> #declare reflector =
> box {
>   <-0.5, -4, -4>, <0, 4, 4>
>   hollow
>   pigment { rgbft <0,1,0,.1,.9> } //White }
>   finish {
>     reflection { 1 }
>   }
>   photons {
>     target
>     reflection on
>     refraction on
>   }
>   rotate z * 45
>   translate x * -9
> }
> object { reflector }
> 
> 
> in place of current reflector, I dont know why I am see what I am seeing.
> 3 beams reflected and transmitted? well I really cant see it yet, very slow.
> 
> render center region with drag, low low res
> 
> next logical step experiment with prism shape , perhaps other shapes
> 
> 
> 
> 
In that situation, it's obvious that you should see multiple beams.

A beam that reflect off the front surface.
A first transmited beam that goes out of the back.
Another that goes into the box, reflect off the back and emerge a little farther.
When it reatch the front face, part of the beam get reflected back into the box.
This gives you the second beam exiting from the back after 2 reflections.
Yet another that reflect trice inside the box.
A forth that have reflected 5 times.
Then a fift after 7 reflections...
Each successive beam become dimer, and, in your case, the forth one is to faint 
to be seen.

If you add "conserve_energy" you'll notice that the extra beans goes away.


-- 
Alain
-------------------------------------------------
Tricks and treachery are the practice of fools, that don't have brains enough to 
be honest.
Benjamin Franklin

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"Jim Holsenback" <jho### [at] hotmailcom> wrote in message 
news:487f99e7@news.povray.org

thanks everyone who has added to this thread! i've discoverd something that 
may lend to the discussion .....

my initial scene was correct but the problem that I was having had nothing 
to do with photon set up or geometry. after trial and error I think I solved 
a conflict with the emitter beam size (radius, falloff and tightness) and 
the global photon block parameter spacing. just as a reminder my inital 
problem was that light beam not appearing to be sent on to the target by the 
reflector object. I've hit on a compatable combination with those 
parameters, however the reflected beam still dosen't appear as sharp as the 
beam arriving at the mirror. I see where Alain has mentioned adding 
conserve_energy (multi beam cure) to the finish block on the reflector ..... 
I'm wondering if specular and roughness could help with the problem I'm 
seeing? I'll play around with that when I get a moment ..... in the mean 
time any additional input would be appreciated.

Cheers
Jim

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Jim Holsenback nous illumina en ce 2008-07-20 10:37 -->
> "Jim Holsenback" <jho### [at] hotmailcom> wrote in message 
> news:487f99e7@news.povray.org
> 
> thanks everyone who has added to this thread! i've discoverd something that 
> may lend to the discussion .....
> 
> my initial scene was correct but the problem that I was having had nothing 
> to do with photon set up or geometry. after trial and error I think I solved 
> a conflict with the emitter beam size (radius, falloff and tightness) and 
> the global photon block parameter spacing. just as a reminder my inital 
> problem was that light beam not appearing to be sent on to the target by the 
> reflector object. I've hit on a compatable combination with those 
> parameters, however the reflected beam still dosen't appear as sharp as the 
> beam arriving at the mirror. I see where Alain has mentioned adding 
> conserve_energy (multi beam cure) to the finish block on the reflector ..... 
> I'm wondering if specular and roughness could help with the problem I'm 
> seeing? I'll play around with that when I get a moment ..... in the mean 
> time any additional input would be appreciated.
> 
> Cheers
> Jim 
> 
> 

conserve_energi is only needed when you have transparency AND reflection.

It's usual for the reflected part to not be as sharp as the incident beab.

The specular and roughness have nothing to do with reflection, the affect 
specular highlights. They do the same as phong/phong_size, but with a different 
model.


-- 
Alain
-------------------------------------------------
   A girl phoned me and said, "Come on over. There's nobody home." I Went over. 
Nobody was home!
	Rodney Dangerfield

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