Looking for a fake GI plugin.

[Per-Anders]

well mograph can do that, ditools can do that, i believe chestnuts might have done that, i don't know if 50grey did that...

[danb]

Whoops i meant something else. I mean HDRI. So when there's an image texture on the dome the lighting color changes according to the color of the image texture.

[Jorge Arango]

Whoops i meant something else. I mean HDRI. So when there's an image texture on the dome the lighting color changes according to the color of the image texture.

Lumen from 3dAttack?


Jorge Arango

[danb]

Lumen from 3dAttack?


Jorge Arango

Yes exactly what i had in mind. Thank you.

[Per-Anders]

glad to see you found what you were looking for, but just so you know those other plugins will do that too (an hdri is after all only a bitmap with a higher gammut).

[danb]

glad to see you found what you were looking for, but just so you know those other plugins will do that too (an hdri is after all only a bitmap with a higher gammut).

Mograph you say? Yet another reason to learn it. Thanks.

[vesalus]

you definitly talk about 50 grey, it changes an image or an hdri file to a dome of lights, it gives some good results in some case

[pzdm]

you definitly talk about 50 grey, it changes an image or an hdri file to a dome of lights, it gives some good results in some case

Do you hate hemisphere light? Why don´t you use hemisphere (or sphere) light and material with hdri map in transparancy channel? You can use AO effect, too...

[JoelOtron]

Do you hate hemisphere light? Why don´t you use hemisphere (or sphere) light and material with hdri map in transparancy channel? You can use AO effect, too...

I was wondering the same thing...

[danb]

Do you hate hemisphere light? Why don´t you use hemisphere (or sphere) light and material with hdri map in transparancy channel? You can use AO effect, too...

I don't understand what you are talking about? Please explain.

[vesalus]

if i use an hemisphere light with an hdr in the transparency slot i've got an image projection on the ground

[skydistortion]

Could someone provide an example of image rendered using that technique or C4D files to look closer ?

[v-empire]

I think what you want is what i do often with lumen.
The hdri gives colors to the pointlights that are spread over a hemispere,
and it can adjust the brightness of each pointlight acoording to the hdri.

That´s very similar to gi (exept the bounces)

If you put a hdri into the transparency channel of an area light that is
set to hemisphere its more like a slide projection. In any case it doesn´t look
as good as lumen, comes not even close.

If you use Lumen you have to use a high pointlight distribution if you take the brightness from the hdri, cause the shadows of each pointlight get more obvious.
I you use the hdri only for coloring the hemisphere of pointlights, you don´t need a distribution of lights that is so high, but you get only some kind of half the way gi look.


Regards
Holger

[JoelOtron]

I think what you want is what i do often with lumen.
The hdri gives colors to the pointlights that are spread over a hemispere,
and it can adjust the brightness of each pointlight acoording to the hdri.

That´s very similar to gi (exept the bounces)

If you put a hdri into the transparency channel of an area light that is
set to hemisphere its more like a slide projection. In any case it doesn´t look
as good as lumen, comes not even close.

If you use Lumen you have to use a high pointlight distribution if you take the brightness from the hdri, cause the shadows of each pointlight get more obvious.
I you use the hdri only for coloring the hemisphere of pointlights, you don´t need a distribution of lights that is so high, but you get only some kind of half the way gi look.


Regards
Holger

You are correct about the hemispheric area light. I hadnt tried this myself--but in the back of my head always assumed it would work.

Apart from Lumen, and Per mentioned, Mograph, Ditools and I beleve Jenna have this same functionality, ie: adjusting each light to the proper color and value based on the bitmap/hdri loaded in. Lumen specializes in this and has some oher cool features too.

[pzdm]

You are correct about the hemispheric area light. I hadnt tried this myself--but in the back of my head always assumed it would work.

Apart from Lumen, and Per mentioned, Mograph, Ditools and I beleve Jenna have this same functionality, ie: adjusting each light to the proper color and value based on the bitmap/hdri loaded in. Lumen specializes in this and has some oher cool features too.

OK, this is my a very old test... But that´s true, there is slight GI settings (intensity 70-80%), too

http://www.3dsoftware.cz/3dportal/clanek.aspx?id=368

few picts:

http://www.3dsoftware.cz/upload/images_clanky/368/012.jpg

http://www.3dsoftware.cz/upload/images_clanky/368/010.jpg

[pzdm]

You must use blured hdri map...
Set higher Samples settings...
If necessary, use Add grain option...
Use large light object...

[JoelOtron]

Interesting pzdm.
I think danb was looking for a fake GI solution, without GI activated.
I'll try your approach with a blurred HDRI--that might reduce the gel preojection effect on the scene.

[pzdm]

Interesting pdzm.
I think danb was looking for a fake GI solution, without GI activated.
I'll try your approach with a blurred HDRI--that might reduce the gel preojection effect on the scene.

I know, but maybe I have somewhere version without GI, too

[benytone]

for a fake GI, i always use AO-material or AO-render, many Light Objects, Environment and
very fine HDRI.
my example:

.
http://img180.imageshack.us/img180/5314/golr1la5.jpg
.

[JoelOtron]

Here are some quick fake gi tests using the c4d built in area light hemi/dome and the mograph method. No materials were tweaked for this--(ie: matching hdri is not in any of the material channels) and settings are somewhat default--hence the grain. Not meant to be a beauty pageant--just for experiments sake.

http://www.betatronstudios.com/cgtalk/fakeGI%20tests.jpg

[pzdm]

Here are some quick fake gi tests using the c4d built in area light hemi/dome and the mograph method. No materials were tweaked for this--(ie: matching hdri is not in any of the material channels) and settings are somewhat default--hence the grain. Not meant to be a beauty pageant--just for experiments sake.



Uff, nice, I tried hemisphere light again, too, becouse I did not find my old files and that´s true, hemisphere light is not suitable for this. I tried move this light up to base plane, but it is not solution. There are not more "light beams", but there is still one central artefact...

Sorry...

[cbowyer]

THere are some quick fake gi tests using the c4d built in area light hemi/dome and the mograph method. No materials were tweaked for this--(ie: matching hdri is not in any of the material channels) and settings are somewhat default--hence the grain. Not meant to be a beauty pageant--just for experiments sake.



The AO certainly adds some nice details into the chrome wheels. I wonder if that's due to the spotlights or the AO (or both). Joel did the render time take much of a hit when you turned on the AO?

[JoelOtron]

T

The AO certainly adds some nice details into the chrome wheels. I wonder if that's due to the spotlights or the AO (or both). Joel did the render time take much of a hit when you turned on the AO?

AO in general is good for accentuating details.
In some cases, using this method (with AO) can be just as time prohibitive as going full GI.

I reduced the number of segments on my hemisphere primitive (onto which the lights are placed) from default 24 to 18, which reduces my lightcount to 101. With default AO added to the scene--the render took 22:48 set to default BEST AA at 720x486. Using spotlights supposedly reduces time, as shadow maps are simpler--and this causes an undesireable stepping to the overlapping shadows on the floor.
A higher light count would have smoothed the shadows, but omni lights with soft shadows would be a more desired look---short of area shadows---which would be crazy--time-wise.

I also tweaked te materials--adding the correct hdri to the env channels and metal-izing the speculars. The result is blown out chrome. I think theres an error with my hubcaps--(edit--there was) maybe I turned off reflection and env. Floor has luminance--so under shadow is too washed out.

I will try again with no shadows on my lights--BUT with a single shadow -only light placed far above.

http://www.betatronstudios.com/cgtalk/with_materials.jpg

EDIT:

Heres the same scene with a shadowcaster and no shadows on the lights.
Time was 16:59--so no shadows knocked off almost 6 minutes.
The shadow is looking worse however. I suppose with some tweaking this scene could become more production friendly for animation.

http://www.betatronstudios.com/cgtalk/shadowcaster.jpg

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