Dear folks,
I've been using POV since '92; I've rendered more than a hundred
scenes.  But the one area that I have made almost no progress in is
cool, realistic lighting.  In the attached ZIP file I am inclosing a
POV, INC, INI, and GIF of one scene for my current project.  There are
two spotlights on a wall above a door.  The lights illuminate the ground
and the surrounding area, but there is no hint of highlighting on the
wall.  I have been tweaking this lighting code on and off for two years
and am no closer to the cone of light than I was at the beginning.

Any help will be wonderful!  Any artist that can provide the proper the
code for the door lights ( and/or all the lights ) will be credited and
praised on my gallery site profusely.
That will be Gallery Four:
http://www.geocities.com/SiliconValley/Network/4969/gall4a.html

A general comment: I've been brousing thru hundreds of POV/ 3D/ graphics
sites in the last two years.  Many, many sites offer tutorials in POV
basics but few if any offer lessions in the advanced features.  If there
are such tutorial pages around I would be grateful to hear about them.
Hell! after I master some advanced stuff, I'll write some lessons
myself!  I was educated to be a high school teacher and I used to be a
decent writer.

Well, thank to all in advance!
--Brendan

--
Michael Brendan Hurley           ShadowDancerEnterprizes, LTD.
http://www.geocities.com/SiliconValley/Network/4969/
http://www.saber.net/~mbhcgc/
mbh### [at] sabernet

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Attachments:
Download 'helpme.zip' (41 KB)

Brendan Hurley wrote:
> 
> Dear folks,
> I've been using POV since '92; I've rendered more than a hundred
> scenes.  But the one area that I have made almost no progress in is
> cool, realistic lighting.  In the attached ZIP file I am inclosing a
> POV, INC, INI, and GIF of one scene for my current project.  There are
> two spotlights on a wall above a door.  The lights illuminate the ground
> and the surrounding area, but there is no hint of highlighting on the
> wall.  I have been tweaking this lighting code on and off for two years
> and am no closer to the cone of light than I was at the beginning.
> 
> Any help will be wonderful!  Any artist that can provide the proper the
> code for the door lights ( and/or all the lights ) will be credited and
> praised on my gallery site profusely.
> That will be Gallery Four:
> http://www.geocities.com/SiliconValley/Network/4969/gall4a.html
> 
> A general comment: I've been brousing thru hundreds of POV/ 3D/ graphics
> sites in the last two years.  Many, many sites offer tutorials in POV
> basics but few if any offer lessions in the advanced features.  If there
> are such tutorial pages around I would be grateful to hear about them.
> Hell! after I master some advanced stuff, I'll write some lessons
> myself!  I was educated to be a high school teacher and I used to be a
> decent writer.
> 
> Well, thank to all in advance!
> --Brendan
> 
> --
> Michael Brendan Hurley           ShadowDancerEnterprizes, LTD.
> http://www.geocities.com/SiliconValley/Network/4969/
> http://www.saber.net/~mbhcgc/
> mbh### [at] sabernet

 I really don't have time to go through all of your code but a quick glance
through the .inc file revealed some pretty low diffuse levels in the wood
textures you are using. If you want them to pick-up highlights from the
spot lights I would suggest you bump them up to diffuse 0.4 - 0.6. At 0.2
they will hardly react with the lights at all. You seem to have the spot
lights set up ok so I doubt they are your problem.
 I also see that you are using Pov v3.0. You owe it to yourself to upgrade
to the newest version of the program which now stands at Pov v3.1 rev G.
There have been several bug fixes plus new features and a superb new editor
for the windows version. I don't recall if Pov v3.0 allowed light settings
higher that one but you can in pov v3.1 have a light source with a much
brighter light that you could in say v2.2 by using values like the following
example:

light_source { <-100, 100, -100> color rgb<10,10,10> }

These brighter lights can give you better control of how it interacts with
surface highlights. It can also wash out a scene quickly if you get carried
away with it.

For a comprehensive list of tutorials both beginner and advanced plus all of
the other Pov goodies you could ask for see my links collection posted in the
announcement group
here on this server.

P.S. This is a non binaries group. Instead of posting your source here you
should have posted your question here and then posted the source in the
povray.binaries.scene-files
group with a message saying the source could be
viewed there.

-- 
Ken Tyler
  
mailto://tylereng@pacbell.net
http://home.pacbell.net/tylereng/links.htm

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Ken <tyl### [at] pacbellnet> wrote:
: light_source { <-100, 100, -100> color rgb<10,10,10> }

  I prefer the shorter version:

  light_source { <-1, 1, -1>*100, 10 }

: These brighter lights can give you better control of how it interacts with
: surface highlights. It can also wash out a scene quickly if you get carried
: away with it.

  Setting the brightness of the light sources to much more than 1 will give
you a high contrast and overexposed highlights.
  If, however, you want just to light up your scene, you can:
a) set a higher global gamma
b) set a higher global ambient_light (I prefer this one) (the default is 1 if
   I remember correctly)

  To get realistic looking lighting, you could also try with fading light
(fade_power 2 is the best) and of course setting proper finishes to the
textures of your objects.

-- 
main(i,_){for(_?--i,main(i+2,"FhhQHFIJD|FQTITFN]zRFHhhTBFHhhTBFysdB"[i]
):5;i&&_>1;printf("%s",_-70?_&1?"[]":" ":(_=0,"\n")),_/=2);} /*- Warp -*/

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On Thu, 05 Aug 1999 20:47:00 -0700, Ken wrote:
>I don't recall if Pov v3.0 allowed light settings
>higher that one but you can in pov v3.1 have a light source with a much
>brighter light that you could in say v2.2 by using values like the following
>example:

v2.2 allowed components higher than one.  I'm not aware of any version
that didn't, but I really got started with POV again in 2.2.  The only
version I'd used before that was too long ago to remember.

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Nieminen Mika wrote:
> 
> Ken <tyl### [at] pacbellnet> wrote:
> : light_source { <-100, 100, -100> color rgb<10,10,10> }
> 
>   I prefer the shorter version:
> 
>   light_source { <-1, 1, -1>*100, 10 }

I prefer the shorter version too but after looking at the source provided
I opted for consistancy of syntax rather that yeilding to the temptation
of inserting my own style :)

-- 
Ken Tyler
  
mailto://tylereng@pacbell.net
http://home.pacbell.net/tylereng/links.htm

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Ron Parker wrote:
> 
> On Thu, 05 Aug 1999 20:47:00 -0700, Ken wrote:
> >I don't recall if Pov v3.0 allowed light settings
> >higher that one but you can in pov v3.1 have a light source with a much
> >brighter light that you could in say v2.2 by using values like the following
> >example:
> 
> v2.2 allowed components higher than one.  I'm not aware of any version
> that didn't, but I really got started with POV again in 2.2.  The only
> version I'd used before that was too long ago to remember.

This may have been true but I did not know about it because the v2.2 docs do
not mention that it is possible and I picked up on the idea here in these
news groups. Just doing my part to pass on what is not intuitively obvious
to everyone.

-- 
Ken Tyler
  
mailto://tylereng@pacbell.net
http://home.pacbell.net/tylereng/links.htm

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On Fri, 06 Aug 1999 08:21:24 -0700, Ken wrote:
>
>
>Ron Parker wrote:
>> 
>> On Thu, 05 Aug 1999 20:47:00 -0700, Ken wrote:
>> >I don't recall if Pov v3.0 allowed light settings
>> >higher that one but you can in pov v3.1 have a light source with a much
>> >brighter light that you could in say v2.2 by using values like the following
>> >example:
>> 
>> v2.2 allowed components higher than one.  I'm not aware of any version
>> that didn't, but I really got started with POV again in 2.2.  The only
>> version I'd used before that was too long ago to remember.
>
>This may have been true but I did not know about it because the v2.2 docs do
>not mention that it is possible and I picked up on the idea here in these
>news groups. Just doing my part to pass on what is not intuitively obvious
>to everyone.

Of course.  I don't begrudge you that.  I'm just doing my part to tell
both people who are still using 2.2 that they can use big components 
too. :)

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Ron Parker wrote:
> 
> On Fri, 06 Aug 1999 08:21:24 -0700, Ken wrote:
> >
> >
> >Ron Parker wrote:
> >>
> >> On Thu, 05 Aug 1999 20:47:00 -0700, Ken wrote:
> >> >I don't recall if Pov v3.0 allowed light settings
> >> >higher that one but you can in pov v3.1 have a light source with a much
> >> >brighter light that you could in say v2.2 by using values like the following
> >> >example:
> >>
> >> v2.2 allowed components higher than one.  I'm not aware of any version
> >> that didn't, but I really got started with POV again in 2.2.  The only
> >> version I'd used before that was too long ago to remember.
> >
> >This may have been true but I did not know about it because the v2.2 docs do
> >not mention that it is possible and I picked up on the idea here in these
> >news groups. Just doing my part to pass on what is not intuitively obvious
> >to everyone.
> 
> Of course.  I don't begrudge you that.  I'm just doing my part to tell
> both people who are still using 2.2 that they can use big components
> too. :)

  Ok I can accept that... I think :)

-- 
Ken Tyler
  
mailto://tylereng@pacbell.net
http://home.pacbell.net/tylereng/links.htm

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Dear Ken and Nieminen and Ken and others,

Thanks for the replies to my questions.  This is my very first participation in any
news groups so I am just learning the protocols of posting.  Thanks for the advice.

I had a feeling that the lighting problems might have something to do with the surface
textures and finishes.  I will continue the tweaking process and will let you all know
what I come up with.

About upgrading my POV version:  I have been saving money, scrounging old equipment,
trading labor for computer tech help for two years.  Tomorrow, by some cosmic
coincidence, I will recieve my first Pentium I mother board, a new larger HD and the
long-awaited upgrade to WIN 95.  So today I plan to download the newest POV for
Windows.  My hesitation to go to POV-Win was "I don't want to rewrite, re-render all
these scenes again!" but the forces of the Gods of Upgrades have now spoken.

Blessings,
   Brendan
--
Michael Brendan Hurley           ShadowDancerEnterprizes, LTD.
http://www.geocities.com/SiliconValley/Network/4969/
http://www.saber.net/~mbhcgc/
mbh### [at] sabernet

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Brendan Hurley <mbh### [at] sabernet> wrote:
: My hesitation to go to POV-Win was "I don't want to rewrite, re-render all
: these scenes again!"

  Why would you have to rewrite all your scenes?

-- 
main(i,_){for(_?--i,main(i+2,"FhhQHFIJD|FQTITFN]zRFHhhTBFHhhTBFysdB"[i]
):5;i&&_>1;printf("%s",_-70?_&1?"[]":" ":(_=0,"\n")),_/=2);} /*- Warp -*/

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