Hi,

I have a hard time getting a brighter result. What I've achieved so far:
http://blackbox.diitstudio.com/download/result.png

I use radiosity without conventional lights, and use sky_sphere:
sky_sphere {pigment {color rgb <3.16, 3.56, 4>}}

I don't want (direct) sunlight and want to leave the radiosity parameter
brightness at 1 if possible.

For most objects I use a "flat" finish:
finish {diffuse 0.6 phong 0}

Is the dark image a result of not using a light source? Or am I forgetting to
set something in the finish/texture?
Even adding an ambient value of 0.5 to the finish doesn't make it any brighter.

Any help is appreciated.


Regards,
Dick

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> I have a hard time getting a brighter result. What I've achieved so far:
> http://blackbox.diitstudio.com/download/result.png
>
> I use radiosity without conventional lights, and use sky_sphere:
> sky_sphere {pigment {color rgb <3.16, 3.56, 4>}}

Is there a reason you don't want to use a brighter sky_sphere? eg:

sky_sphere {pigment {color rgb 5*<3.16, 3.56, 4>}}

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BTW: what I'm really asking is how to let the materials reflect more light, so
the total scene becomes brighter.

In this next example I multiplied the sky_sphere color with 4:
http://blackbox.diitstudio.com/download/result2.png

Now the bright areas "wash out". This is best seen in the treshold and the frame
of the doorway, while the area around door and window becomes much brighter, the
rest of the interior stays dark, as is rather noticable for table and chairs.

Post a reply to this message

> Hi,
>
> I have a hard time getting a brighter result. What I've achieved so
> far: http://blackbox.diitstudio.com/download/result.png
>
> I use radiosity without conventional lights, and use sky_sphere:
> sky_sphere {pigment {color rgb <3.16, 3.56, 4>}}
>
> I don't want (direct) sunlight and want to leave the radiosity
> parameter brightness at 1 if possible.
>
> For most objects I use a "flat" finish: finish {diffuse 0.6 phong 0}

   If you don't use reflection, then raise the diffuse to 1.

> Is the dark image a result of not using a light source? Or am I
> forgetting to set something in the finish/texture?

   I guess what you want is more light bounces... what is your
recursion_limit? To me it looks like you have currently only 2... better
raise it up to 3 or even 4.

> Even adding an ambient value of 0.5 to the finish doesn't make it any
> brighter.

   BTW, do not EVER use ambient if you want realistic results.

--
jaime

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Am 23.02.2016 um 11:06 schrieb Jaime Vives Piqueres:

>> Even adding an ambient value of 0.5 to the finish doesn't make it any
>> brighter.
> 
>   BTW, do not EVER use ambient if you want realistic results.

That's ok. I presume Dicko is using a "#version 3.7" statement, in which
case "ambient" is de-activated anyway when radiosity is enabled ;)

Post a reply to this message

> BTW: what I'm really asking is how to let the materials reflect more light, so
> the total scene becomes brighter.
>
> In this next example I multiplied the sky_sphere color with 4:
> http://blackbox.diitstudio.com/download/result2.png
>
> Now the bright areas "wash out". This is best seen in the treshold and the frame
> of the doorway, while the area around door and window becomes much brighter, the
> rest of the interior stays dark, as is rather noticable for table and chairs.

Exactly what material definition have you got for the walls and ceiling?

Post a reply to this message

> Hi,
>
> I have a hard time getting a brighter result. What I've achieved so far:
> http://blackbox.diitstudio.com/download/result.png
>
> I use radiosity without conventional lights, and use sky_sphere:
> sky_sphere {pigment {color rgb <3.16, 3.56, 4>}}
>
> I don't want (direct) sunlight and want to leave the radiosity parameter
> brightness at 1 if possible.
>
> For most objects I use a "flat" finish:
> finish {diffuse 0.6 phong 0}
>
> Is the dark image a result of not using a light source? Or am I forgetting to
> set something in the finish/texture?
> Even adding an ambient value of 0.5 to the finish doesn't make it any brighter.
>
> Any help is appreciated.
>
>
> Regards,
> Dick
>
>
>

Why use a sky_sphere for a plain, uniform colour. Beter to use 
background{ rgb <3.16, 3.56, 4>*Intensity } in this case.

When using the current version (3.7) and radiosity, ambient is set to 
zero everywhere. If you want luminous surfaces, use emission. This will 
make the texture actualy emit light. An emissive texture should have a 
lower diffuse than normal.

You can make your background even brighter by multiplying it's colour by 
some value.

recursion_limit default to 2. You may want to increase it to 3 or 4, or 
even 5. Going above 5 will usualy have negligeable effect.

You may increase the diffuse value somewhat. Try 0.8 to 0.9. You should 
not use diffuse 1 if you want to get realistic results.



Alain

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Reminds me for my earlier problem: I used the old, almost obsolete
"ambient" instead of the new, better "emission".






On 23.02.2016 09:46, clipka wrote:
> Am 23.02.2016 um 11:06 schrieb Jaime Vives Piqueres:
> 
>>> Even adding an ambient value of 0.5 to the finish doesn't make it any
>>> brighter.
>>
>>   BTW, do not EVER use ambient if you want realistic results.
> 
> That's ok. I presume Dicko is using a "#version 3.7" statement, in which
> case "ambient" is de-activated anyway when radiosity is enabled ;)
>

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Hi all,

Thanks for all your answers.
I was away for a while, so that's why you did not get any reaction from me.

I will try your suggestions in the coming days and will let you know the
results.


Regards
Dicko

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