"Lars C. Hassing" wrote:
> 
> > http://luxlab.com/tmp/lego.jpg
>
> But please shed some light on me too - how did you do it ?

I'll mail you the changed code when I get it cleared.


Here is the short list of steps applied to the code.

1. Monitors distort the light intensities. assumed_gamma
   compensates the CRT response. Post-processing would give more
   freedom to set the lighting but as it's not available, adjusting
   gamma will have to do. I did do moderate post work on the image
   to "sell" it better :)

2. Colors used without gamma correction have to be altered
   to appear correctly. ambient 0 for all textures except sky.

3. The camera is 35mm with 50mm focal length.

4. The two spot lights are circular area lights. The main light
   has a yellow tint which produces white when mixed with the sky
   light. It's also close to the model to emphasize the scale. The
   back light brings out features on top of the model. Sky dome
   emits blue light when radiosity is used and makes the shadows
   blue. It's like a miniature outdoors scene set on a table top.

5. The lighting was designed for radiosity but similar results can
   be achieved by adding many blue fill lights. I prefer radiosity
   as it produces some very nice light interactions within the model.

I left reflections and normals as they were so they may not be
so realistic. The rendering was done in two parts. First without
aa, area light modifiers, and DOF at 37% size to get radiosity data.
The image was thrown away. The radiosity data was reused in the final
render. The idea was to separate the costly area light, DOF and
radiosity sampling to gain speed. I hope it worked.


> "overused light dome/light tent setup"

Well, it may be new to the LEGO crowd but it doesn't look so nice
after the 100th scene. The lighting is pure radiosity as the whole
sky dome emits the light. It's like being in the middle of a snowy
plateau under 100% cloud cover. Photographers use light tent to light
glass objects, for example. Put objects and the camera in the tent,
point lights on the tent from all sides and take the picture.

Dome lighting is faster than the two light setup and the good thing
about it is: one size fits all :)

 
_____________
Kari Kivisalo

Post a reply to this message