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limkinkwan
05-21-2004, 07:14 AM
Hi all, can any give me some advise about lightning?

Now my scene cathedral interior, there is some fog, volumetric effect..., I try to make the scene looks real, can anyone giV some suggestion to me how to make the light to be real but fast rendering ? i 've tried to use f-prime, but takes long time to render, (I also dun know y, maybe my scene is high poly), overcaster is not suitable for interior, radiosity takes too long for render also, so can anyone help me? :)

gerardo
05-21-2004, 10:00 AM
Tell me, why do you say that Overcaster is not suitable for interiors? maybe is not very obvious its use, but if you understand its operation principle, I think that is really good. Some time ago I made this very simple test scene, just to show the Innercaster use in interiors:

http://www.geocities.com/gerardstrada/testroomvol.txt

although isn´t an ultra-realistic image, isn´t bad for 2 minutes of render (without taking into account volumetrics). If you have F-Prime, test Innercaster and change the spot lights for area lights, F-Prime calculates area lights quickest than spot lights for what you will obtain better results in less time. If your scene is for animation you can use radiosity and to bake the illumination in textures, or to illuminate without radiosity and then make an ambient occlusion map to give some volume to your scene.
Perhaps would be good that you post some images of what you have there.


Best Regards


Gerardo

limkinkwan
05-22-2004, 04:10 AM
Hi gerardo, sorry for late reply!
Her is the cathedral, the top right takes around 30 minute to render In Fprime and Lightwave rendering. Innercaster I will try it later on.:)

http://www.geocities.com/kkdsign/allhere.html

Mechis
05-22-2004, 04:29 AM
What was your technique for making the trees? Looks good!
~Mechis

gerardo
05-22-2004, 08:17 AM
Your work looks realy good! :thumbsup:
Mainly the first two images, the second (pic 3 and 4) looks a little bit dark, in reality the opening (hole) of the third image should illuminate more the cathedral interior, but that depends on the atmosphere that you want to achieve; personally I like a lot, your textures work is excellent, is noticed that you have a lot of time of work in them. Only the last 2 images looks a little artificial; not for the shadows but for the tonal valuation of the diffusion in the walls, is very uniform (pic 5); test making the superior part, lighted; to the center, darkest; and nearby to the floor, lighted again, but not as much as the superior part; the idea is that a diffuse light comes from the superior windows, and it decays toward the inferior areas, but the floor to being a reflecting surface, reinforces the lower illumination a little. This can solve it with a diffusion map.
I think a good option in this case would be to bake the illumination in the textures, not necessarily the whole structure since apparently, this is formed by same modules, bake one module and repeat them in the other ones.
If you go for Innercaster option, I recommend you segment the structure for parts, and to these, separate the ceiling of the walls; the idea is that Innercaster covers square areas, not rectangular; for a bigger illumination control, is advisable to separate the lights that will affect difuse, of the lights that will cast shadows; a useful Innercaster option is that you can give it tonalities slightly different to the walls, ceiling and floors; as well as to the shadows very easily.
More than illumination, maybe the reason for which you are not totally happy with your images is for the use of depth of field; the use of the DOF is a little inexact; in the first two images the shots are achieved with very open camera angles, what causes that DOF is minimum (sharp backgrounds), otherwise it would seem a miniature; on the contrary in the third image the angle of the lens is more shut, what the DOF should pronounce (blurred backgrounds).
The last image only needs a little more work. What time of the day is? from where comes the sun light? of what year season are we speaking? the season of the year is very important since offers the color tonalities that will help to give mood to your final image. The sky seems summer but the illumination is diffuse, what makes me think of winter or autumn, but the plants have a spring greenery. Would be good to define these concepts that even have incidence in the interior illumination. I think that if the hills are blued, they should be more far, this is an effect taken place by the the atmosphere and distance; you also need a transition between the floor of the cathedral front and the most distant floor, the shadow in the base of the front columns, make seem the cathedral floats. :)
A sure way of visualizing the illumination, is to define the concept and the function that this fulfills, will reinforce a theme or central point? should be dramatic, terrifying, of dream, fantasy, etc. to define the concept or the function is very important to achieve a coherent and unifier result.
You have an excellent work there, congratulations man!:thumbsup:


Best regards,


Gerardo

limkinkwan
05-22-2004, 12:31 PM
THANKS your suggestion and comment gerardo :cool:, but I still don't understand why Fprime doesnt render fast for my cathedral, is anyone get this problem before, even the last image(Landscape) when I render or preview, it HANG!!! :wise:

Mechis - Most of the tree I use ClipMap method, Which mean I build a few plane with UV map(leave texture), than clone it a lot and put it on your tree trunk, and then send it to Layout, under object properties>Render>Clipmap(The texture should be in grayscale alpha map) dark area will show, and white area is invisible, thats all.

:)

limkinkwan
05-22-2004, 08:03 PM
And how about HDRI setup, is it suitalbe for interior? I never try this before, can anyone tell me ?
:)

gerardo
05-23-2004, 12:30 AM
As I´ve understood, the FPrime render delays the same than LW if your objects are by layers. If you have objects by layers, separate them in independent objects and test again.
In the concerning to HDRI, unless you use Monte Carlo Radiosity or Interpolated you won't obtain more color variations than those that enter for the windows (that is already enough). If you want color variations of the "vitrails" (the big painted windows), you can use TGALH (The Great Textured Area Light Hack) of Court Jester. Is a quicker and more controllable way to get nice color variations of the lights that enter for the windows or even inside the cathedral.


Gerardo

gerardo
05-23-2004, 08:43 AM
I forgot, if you want the volumetrics lights has the colors of the "vitrails" images, use this images like projection images in the volumetric lights. This works much better with HDR images.


Gerardo

limkinkwan
05-26-2004, 02:51 AM
Hey, Gerado, I do like the first image you post, great:thumbsup: But , for my cathedral I can't really acheive to that rusult... I 've segment the structure for parts, and separate the ceiling of the walls ( no cast shadow), but the result just feel strange....am i make something wrong?

http://www.geocities.com/kkdsign/innercaster.html

limkinkwan
05-26-2004, 02:54 AM
Or do you want to try it on my cathedral ?:)

gerardo
05-26-2004, 05:17 AM
Of course. Send me it to this e-mail:

gerardstrada@yahoo.com

I´ll see what I can do :)


Gerardo

limkinkwan
05-28-2004, 09:19 AM
some update, comment pls, the first one, I don't know why some of the texture is broken when I use volumetric, anyone solution for this?:)


http://www.geocities.com/kkdsign/hunpin1.html
http://www.geocities.com/kkdsign/hunpin2.html

limkinkwan
05-28-2004, 09:47 AM
http://www.geocities.com/kkdsign/pinpin3.html
http://www.geocities.com/kkdsign/pinpin4.html

gerardo
05-28-2004, 12:44 PM
Hey! this looks good! :beer:
Sorry for delay, I´ve been a little busy. I made this basic illumination test with a module and Innercaster:

http://www.geocities.com/gerardstrada/Testcath.txt



http://www.geocities.com/gerardstrada/testcath2.txt


The link you gave me didn't have the textures, so I made it without them, but is better this way for illumination test.
The time of this, to small size is 9m 12s and to normal size 11m 58s.
Now I´m sending you the files, if the times convince you, you can adapt it to the atmosphere and mood that you´re looking for; however I think that to bake the illumination in the textures can make the quickest render (mainly for the structure) and you can use the spinning lights for the objects that move inside.
The problem that you mention is maybe due to the volumetrics lights texture or the windows textures. Are you using Color Filter for the windows?




Gerardo

limkinkwan
05-28-2004, 05:47 PM
Wao! Looks GREAT Gerardo! Can't wait to get the files...11m 58s for rendering time is pretty fast.

For the Volumetric error...I don't use any color filter, When I turn off the Volumetric light everything looks fine, but when I turn it on, the error was happen...:hmm:

gerardo
05-29-2004, 03:31 AM
Thanks!
I already sent you an e-mail with a link to the files. (your e-mail is full)
What I made was to divide the structure in modules and to make a rig for each module (excluding the other lights of the geometry that it doesn't correspond it) then I added an OC_Window and spinning bounce lights that affect indiscriminately to all the modules.
If you study the rig I am for sure you will be able to apply the principle to the rest of the structure or to the character.
With regard to volumetrics; What type are you using, spot? distant? raytrace?
If you are using spot; do you have an image in projection image?



Gerardo

limkinkwan
05-29-2004, 04:07 AM
Yup, I'm using Spotlight but no projection:) Thanks for your files !

gerardo
05-29-2004, 04:16 AM
:thumbsup:


Perhaps you don't have activated Volumetric Antialiasing option ???


Gerardo

limkinkwan
05-29-2004, 08:53 AM
yes! it solve the problem! I set the the best quality, thanks again Gerardo:bowdown:

gerardo
05-29-2004, 09:15 PM
:thumbsup:

limkinkwan
05-30-2004, 12:58 PM
hey everybody, please giV some comment for this!:eek:
http://www.geocities.com/kkdsign/email.html

uncommongrafx
05-30-2004, 01:59 PM
Made me chuckle the difference. Looks like some learnin' happened!!

gerardo
05-30-2004, 11:43 PM
The only thing that I see a little bit rare is the lights direction that enter through the windows and the shine of the big window of the right.
Besides that, I think that looks very good, has a well achieved mystery atmosphere. :thumbsup:



Gerardo

dies-irae
05-31-2004, 12:34 PM
right now you can guess the distance of the volumetric light, and there's no sun or moon that near :p either set the volumetric to cylindrical or put it a lot farther away.

i'm not too sure about that specular. In my experience i have yet to see such brights metals on a cathedral, they kinda stray too far away from the rest of the surfaces. The little brownish low-reliefs just above the metallic strips look so good, i'd use those as a reference for the strips beneath

and a last detail: the texture on the archway on the upper right has the same bricky pattern as the rest of the wall, it's kinda weird.

That said, i really like the mood of the renders, the lightning gives a misterious touch and a calmness that really does it! looking forward to see how it evolves!

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