There seems to be a default light source in 3.7 Beta 34.
When I turn all light sources off and set global_settings{ambient_light 0} in
3.6 I get a black image, but 3.7 gives a dusk ambient lighted image. All my
scenes tend to be allot brighter in 3.7 than in 3.6.

I googled and bingd on how to turn this off without success, or is it something
else?

Cheers,
Louis

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"Louis" <nomail@nomail> wrote in message 
news:web.4b02c77e4c442a2e27a6896b0@news.povray.org...
> There seems to be a default light source in 3.7 Beta 34.
> When I turn all light sources off and set global_settings{ambient_light 0} 
> in
> 3.6 I get a black image, but 3.7 gives a dusk ambient lighted image. All 
> my
> scenes tend to be allot brighter in 3.7 than in 3.6.
>
> I googled and bingd on how to turn this off without success, or is it 
> something
> else?

sounds like gamma handling issue ... check out the threads in this newsgroup 
that discuss gamma and see if that sheds any light (no pun intended) on your 
issue.

Jim

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> sounds like gamma handling issue ... check out the threads in this newsgroup
> that discuss gamma and see if that sheds any light (no pun intended) on your
> issue.
>
> Jim

"#version 3.6" did the trick, thanks!

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Louis wrote:
>> sounds like gamma handling issue ... check out the threads in this newsgroup
>> that discuss gamma and see if that sheds any light (no pun intended) on your
>> issue.
>>
>> Jim
> 
> "#version 3.6" did the trick, thanks!

You may also use #default{finish{ambient 0}} anywhere in your scene 
file. 3.7 gives me no problems this way.

Happy Povving,

Sam

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stbenge <UN### [at] hotmailcom> wrote:
>
> You may also use #default{finish{ambient 0}} anywhere in your scene
> file. 3.7 gives me no problems this way.
>
> Happy Povving,
>
> Sam

This woudln't do the same actually.
To have the same result as 3.6, you have to change the gamme in the ini settings
:
Display_Gamma=1.0 File_Gamma=1.0

This is because the default gamma changed from 1.0 in povray 3.6 to 2.2 in
povray 3.7 ; so if you just change back the gamma, everything will be back to
normal. And this isn't the same as turning off default ambient, because even
with gamma 1.0, unlit objects will look dark but not black.

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Gyscos wrote:
> stbenge <UN### [at] hotmailcom> wrote:
>>
>> You may also use #default{finish{ambient 0}} anywhere in your scene
>> file. 3.7 gives me no problems this way.
>>
>> Happy Povving,
>>
>> Sam
> 
> This woudln't do the same actually.
> To have the same result as 3.6, you have to change the gamme in the ini
> settings
> :
> Display_Gamma=1.0 File_Gamma=1.0
> 
> This is because the default gamma changed from 1.0 in povray 3.6 to 2.2 in
> povray 3.7 ; so if you just change back the gamma, everything will be back
> to normal. And this isn't the same as turning off default ambient, because
> even with gamma 1.0, unlit objects will look dark but not black.

Total black should be unaffected by any gamma correction...

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Nicolas Alvarez <nic### [at] gmailcom> wrote:

> Total black should be unaffected by any gamma correction...

Indeed, that's why gamma and ambient-light can't do the same thing.

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>> Total black should be unaffected by any gamma correction...
>
> Indeed, that's why gamma and ambient-light can't do the same thing.

The OP apparently has(had?) two problems:

1) Even with no light sources and ambient light turned off the scene was not 
black.  AIUI this would be a bug as the output should be totally black no 
matter what the gamma setting is.

2) All scenes look lighter in 3.7 compared to 3.6.  This is because 3.7 has 
gamma correction applied by default.  You should fix your scene to make it 
look how you want (because you need gamma correction to make the lighting 
look physically correct on your monitor), or if you're lazy just turn off 
gamma correction to get the same output as 3.6 gave by default.

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scott <sco### [at] scottcom> wrote:
> 1) Even with no light sources and ambient light turned off the scene was not 
> black.  AIUI this would be a bug as the output should be totally black no 
> matter what the gamma setting is.

  That actually depends on the contents of the scene. For example emitting
media doesn't care about light sources (or lack thereof) or ambient settings.

-- 
                                                          - Warp

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