In article <3ea3055e@news.povray.org>, Warp <war### [at] tagpovrayorg> 
wrote:

>   All this to simply get some white dots on the image?-)

Nah, so people won't ask where the stars are. ;-)

Really, having a visual background of some sort would be useful, just 
for ease of mind, or for judging changes in orientation on the fly 
(assuming you would ever need to do so). You could have the computer 
project a background grid, but why not just make something that is 
already there visible? Also, the idea is to mimic what the eye would 
see, and it can adapt so the stars are visible. You can see the stars 
when standing on the sunlit side of the moon, it's just hard to catch 
them on film. And you'll probably have these types of sensors anyway, 
they would be lighter than multiple cameras.


>   Space movies often exaggerate the beautiness of stars in space, but
> I wouldn't be surprised if actually they were just extremely boring
> white dots... :)

Are you saying the astronauts we've sent up are exaggerating too?


>   The images of the Hubble telescope are marvelously beautiful... But those
> images are photographind details thousands of light-years big. You don't
> get that kind of colorful images when photographing a planet or a
> spaceship...

And they're nothing like what this camera would show. They are not what 
it is intended to show. Having a ship go through a densely foggy nebula 
is unrealistic, showing stars is not.

-- 
Christopher James Huff <cja### [at] earthlinknet>
http://home.earthlink.net/~cjameshuff/
POV-Ray TAG: chr### [at] tagpovrayorg
http://tag.povray.org/

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Christopher James Huff <cja### [at] earthlinknet> wrote:
>  You can see the stars 
> when standing on the sunlit side of the moon

  I don't think you can see many stars.
  Even here on Earth, if you are in a brightly lit room your eyes are
adapted to the brightness (the size of the pupils and all that stuff)
and it's difficult to see many stars outside, even if it's a dark and
clear night. You need to turn off all lights and wait until your eyes
adapt to the darkness before you begin seeing lots of stars.

-- 
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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In article <3ea40516@news.povray.org>, Warp <war### [at] tagpovrayorg> 
wrote:

>   Even here on Earth, if you are in a brightly lit room your eyes are
> adapted to the brightness (the size of the pupils and all that stuff)
> and it's difficult to see many stars outside, even if it's a dark and
> clear night. You need to turn off all lights and wait until your eyes
> adapt to the darkness before you begin seeing lots of stars.

In that case, the brightness is on your side of the glass, so glare 
masks many of them. Open the window and you can see more stars. Also, 
your eyes move around, adapting to what they are looking at, and have a 
wider dynamic range than most cameras. Just immediately after opening a 
door and walking out of a brightly lit room, I can see many stars, and 
on the Moon there isn't an atmosphere to absorb and scatter so much 
light. From what I've read, the stars are quite brilliant when viewed 
from the Moon.

-- 
Christopher James Huff <cja### [at] earthlinknet>
http://home.earthlink.net/~cjameshuff/
POV-Ray TAG: chr### [at] tagpovrayorg
http://tag.povray.org/

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Christopher James Huff <cja### [at] earthlinknet> wrote:
> In that case, the brightness is on your side of the glass, so glare 
> masks many of them.

  Glass has nothing to do with it.

-- 
#macro M(A,N,D,L)plane{-z,-9pigment{mandel L*9translate N color_map{[0rgb x]
[1rgb 9]}scale<D,D*3D>*1e3}rotate y*A*8}#end M(-3<1.206434.28623>70,7)M(
-1<.7438.1795>1,20)M(1<.77595.13699>30,20)M(3<.75923.07145>80,99)// - Warp -

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In article <3ea44b2d@news.povray.org>, Warp <war### [at] tagpovrayorg> 
wrote:

> > In that case, the brightness is on your side of the glass, so glare 
> > masks many of them.
> 
>   Glass has nothing to do with it.

When you are in a brightly lit room looking out the window (as you gave 
in your example), the glass is very important. The reflection of the 
interior of the room is far brighter than many stars, and covers a much 
wider area. The helmet visor doesn't have a brighter interior to 
reflect, which is why I gave the example of opening a door and glancing 
out. Try it: the stars are visible. From what I've read about what the 
astronauts actually saw, at least when you are facing upward and away 
from the sun, the stars are perfectly visible.

-- 
Christopher James Huff <cja### [at] earthlinknet>
http://home.earthlink.net/~cjameshuff/
POV-Ray TAG: chr### [at] tagpovrayorg
http://tag.povray.org/

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Christopher James Huff <cja### [at] earthlinknet> wrote:
> When you are in a brightly lit room looking out the window (as you gave 
> in your example), the glass is very important.

  Forget the glass. Remove it. Look out the door. Whatever.

> which is why I gave the example of opening a door and glancing 
> out. Try it: the stars are visible. From what I've read about what the 
> astronauts actually saw, at least when you are facing upward and away 
> from the sun, the stars are perfectly visible.

  Do you know the reason why your pupils get larger and smaller depending
on the amount of light?
  When the pupils get smaller, less light gets through and thus you don't
see dimmer light.
  This is the reason stargazers (those using telescopes) never use white
flaslights but red ones. It takes lots of time for the eyes to adapt to
the darkness.
  You may see *some* stars, the brightest ones, but only a minimal percent.

-- 
#macro N(D)#if(D>99)cylinder{M()#local D=div(D,104);M().5,2pigment{rgb M()}}
N(D)#end#end#macro M()<mod(D,13)-6mod(div(D,13)8)-3,10>#end blob{
N(11117333955)N(4254934330)N(3900569407)N(7382340)N(3358)N(970)}//  - Warp -

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On 21 Apr 2003 18:53:50 -0400, Warp <war### [at] tagpovrayorg> wrote:


>  Do you know the reason why your pupils get larger and smaller depending
>on the amount of light?
>  When the pupils get smaller, less light gets through and thus you don't
>see dimmer light.
>  This is the reason stargazers (those using telescopes) never use white
>flaslights but red ones. It takes lots of time for the eyes to adapt to
>the darkness.
>  You may see *some* stars, the brightest ones, but only a minimal percent.
>
You forgot to mention that the dark adapted eye looses colour perception and
goes into greyscale mode. Though I am sure you know that. 

Regards
        Stephen

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In article <3ea4767e@news.povray.org>, Warp <war### [at] tagpovrayorg> 
wrote:

>   Forget the glass. Remove it. Look out the door. Whatever.

Have a hard time breathing on the moon that way, but OK...


>   Do you know the reason why your pupils get larger and smaller depending
> on the amount of light?
>   When the pupils get smaller, less light gets through and thus you don't
> see dimmer light.

I am aware of this. It is the means the eyes use to quickly adapt to 
changes in illumination. It has limits though, and doesn't account for 
the whole adaptive response, it can take hours to fully adapt. It 
doesn't really have anything to do with dynamic range, the range of 
illumination the eye can respond to at one time.
The pupilar response is the reason I referred to glancing out the door. 
It would only take a few moments for substantial adaptation to occur, so 
you would have to do it quickly enough that your eyes were mostly 
adapted to the room.


>   You may see *some* stars, the brightest ones, but only a minimal percent.

And you said the stars were invisible. I said they are visible, not that 
it was optimal viewing conditions. (though if you shield the sun and 
surroundings, it is ideal)

-- 
Christopher James Huff <cja### [at] earthlinknet>
http://home.earthlink.net/~cjameshuff/
POV-Ray TAG: chr### [at] tagpovrayorg
http://tag.povray.org/

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Christopher James Huff <cja### [at] earthlinknet> wrote:
> And you said the stars were invisible.

  No, I didn't. I said (quote): "it's difficult to see many stars outside".

-- 
#macro M(A,N,D,L)plane{-z,-9pigment{mandel L*9translate N color_map{[0rgb x]
[1rgb 9]}scale<D,D*3D>*1e3}rotate y*A*8}#end M(-3<1.206434.28623>70,7)M(
-1<.7438.1795>1,20)M(1<.77595.13699>30,20)M(3<.75923.07145>80,99)// - Warp -

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Rich <SrP### [at] ricoswebcom> wrote in
news:Xns### [at] 204213191226: 

>   So, realism is not the best option here, but I'd at least like to 
> get rid of the stars that are visible through the sun's "atmosphere"
> and a bit beyond that.

Wow, I didn't expect this kind of response!  I am an amateur astronomer, so 
I do know the whys and wherefors of why stars shouldn't appear in images 
with brighter objects.  At the IMAX film "Space Station" I was asked why 
there weren't any stars in the outside shots (any of them), and I had to 
smile.

Anyway, I'm taking the suggestions by Tek to see if I can achieve the best 
of both worlds, so to speak.  :)

Rich Allen

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