I really appreciate your explanation - too bad you didn't write the 
documentation!  I didn't catch the difference between diffuse and 
specular before.  I will try changing the coding.

Excuse the feeble coding because I have just been doing this this week - 
here is what I have now - 

So far the cross is still 2 separate boxes - I haven't put them together 
yet.  (I'll have to read the documentation for union vs. merge.)  The 
coding I have now is -

#declare F_MetalE  =
finish {
    brilliance 6
    diffuse D_GoldE
    ambient A_GoldE
    
    metallic M
    specular 0.80
    roughness 1/120
} 

box { <.6, .5, 3>, <1.2, .65, 3> 
 texture{
  F_MetalE}
  finish
  {ambient .1
   } 
  } 
 box { <.8, -.4, 3>, <.95, 1, 3> 
  texture{
  F_MetalE}
   finish {ambient .1
   }}   
-- 

I haven't yet made the 2 boxes into one object.  I would have been happy 
to get any kind of light onto any part of either one of those but no 
matter which way  I change the location and look_at of light sources, 
they never show up.  I have sometimes seen a little light on the plane 
but it doesn't seem to be coming from a direction consistent with my 
coding, so obviously I am doing something awfully wrong.  The 
documentation isn't really helpful in this for me.

Christina

http://www.ccbrundage.net/saints/
http://www.ccbrundage.net/
http://web.tampabay.rr.com/ccb/
http://www.thecelticplanet.com/
  "Warp" <war### [at] tagpovrayorg> wrote in message 
news:3ec43c7a@news.povray.org...
    Posting the scene file in question would help finding the problem in
  this case.

    Let me introduce a rather technical explanation about how objects 
"shine"
  when light hits them and how this is achieved in a renderer like 
POV-Ray.

    It's clear that light reflects from objects and that's why we see 
these
  objects in the first place. However, this is a simplification. Light 
can
  reflect from the surface of an object in different ways depending on 
the
  properties of the surface.
    In a simplified lighting model (which is usually enough for making
  good-looking images) there are two ways light can reflect from a 
surface:
  Diffusely and specularly.

    Diffuse reflection assumes the surface is extremely rough at 
microscopic
  level and thus reflects light equally to all directions (all 
directions
  that can be seen from the surface, naturally). Less-technical synonyms 
for
  a diffuse surface are "matte" and "dull". The brightness of the 
surface
  is not dependent on the direction you are looking at it.

    Specular reflection assumes a very smooth surface, with little 
roughness,
  which causes light to be reflected mostly like a mirror does. The 
brightness
  of the surface is highly dependant on where do you look at it from: If
  the light is reflected directly at your eye, you see a bright spot at
  that place in the surface.

    Since most real-life surfaces are not purely diffuse nor specular, 
but
  something in between, this is simulated by calculating both properties
  and adding them together (even though it might not be 100% physically
  correct, it gives a result which looks good enough).

    Now, shiny surfaces are shiny because they have a very high specular
  property to them. They reflect a lot of light specularly (ie. in the
  reflected direction).
    This means that to get a shiny object, you have to specify a high
  specular property to it.

    One requirement for the object to look shiny is that light reflects
  from its surface to the camera. That is, parts of the surface must be
  oriented so that this happens.
    One problem which might arise is if you use objects with sharp edges
  and planar (ie. flat) surfaces. There simply might not be any surface 
on
  the object which is oriented correctly to show a shiny highlight.

    Objects in real life have seldom sharp edges and perfectly planar
  surfaces. Rounding the edges of your object helps a lot (the specular
  highlights will usually appear on the rounded edges because part of
  them will have the right orientation). Naturally positioning the 
camera
  and the light source so that they are at the proper angle with respect
  to a planar surface of the object will give a (usually big) highlight
  on this surface, but that's usually quite artificial (even though
  sometimes it gives a great look to the object).

    So from the above technical mumbo-jumbo we can conclude two 
requirements
  to make your object look shiny:

    1. Define a "finish { specular 1 }" (or a variant) in your object.

    2. Round the edges of your object. (This usually requires some 
modelling
       skills, but that's what rendering is all about.)

  -- 
  plane{-x+y,-1pigment{bozo color_map{[0rgb x][1rgb x+y]}turbulence 1}}
  sphere{0,2pigment{rgbt 1}interior{media{emission 1density{spherical
  density_map{[0rgb 0][.5rgb<1,.5>][1rgb 1]}turbulence.9}}}scale
  <1,1,3>hollow}text{ttf"timrom""Warp".1,0translate<-1,-.1,2>}//  - Warp 
-

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