little
10-06-2002, 09:42 PM
is there a cheap way to get global ilumination in maya or is already there and i just havnt found it yet
View Full Version : global ilumation in maya?
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stunndman
10-06-2002, 10:31 PM
do a forum search - this is a FAQ
Carina
10-07-2002, 09:17 AM
If you are using Maya 4.5 you can download an integrated version of Mental Ray for maya for FREE at www.aliaswavefront.com.
Kabab
10-07-2002, 11:28 AM
Anyone know of any tutorials for mental ray in Maya ???
-wT-
10-07-2002, 01:13 PM
Just a small MR promote ;):
(Rendertime around 10mins... is that good? How much Brazil GI takes normally? The betas I mean, not the superfast 1.0)
(Rendertime around 10mins... is that good? How much Brazil GI takes normally? The betas I mean, not the superfast 1.0)
swag
10-07-2002, 01:42 PM
How u do that wire? is there a new way in mr1.5
-wT-
10-07-2002, 02:14 PM
http://www.kniffen.ca/index.php?target=tutorials/wire/wireTut.php
That, plus a little bit of Photoshop ;)
That, plus a little bit of Photoshop ;)
swag
10-07-2002, 09:09 PM
Hehehe, screen-grab and PS composite ok ... i thought i was a rendering :)
Raptor235
10-08-2002, 03:42 AM
Originally posted by -wT-
Just a small MR promote ;):
(Rendertime around 10mins... is that good? How much Brazil GI takes normally? The betas I mean, not the superfast 1.0)
hey WT how did you setup MR to do a nice render like that I can't get MR to do GI that nicely
Just a small MR promote ;):
(Rendertime around 10mins... is that good? How much Brazil GI takes normally? The betas I mean, not the superfast 1.0)
hey WT how did you setup MR to do a nice render like that I can't get MR to do GI that nicely
wedge
10-08-2002, 05:17 AM
yeah, my MR renders always look like crap. i'm using 1.5beta... i can't simulate sky-type lighting, the only thing i can really do is put a point light around a corner and have the cool indirect illumination, but i can't simulate anything on a grand scale... are there tips or tutorials out there?
Raptor235
10-08-2002, 05:24 AM
ya same here I just went through the docs and played with it for 3 hours got a bit better results but it would really help for some good pointers how many lights what kind of settings ect ect
Raptor235
10-08-2002, 12:23 PM
WT when u read this could you post your settings or maybe attach your file without the mesh so we can check out all the settings it would help us out a lot thanks.
Chappo
10-08-2002, 01:07 PM
/me is hoping for quick release soon of Finalrender for Maya !!!!!
i'm pretty sure it's a mental ray azz kicker
i'm pretty sure it's a mental ray azz kicker
Carina
10-08-2002, 01:14 PM
Having just started using Mental Ray I haven't even had time to try that.
But from what I have been told, the trick to that sort of lighting is to use an object as a light source, and then use final gathering.
(or, if you're not using final gathering that might be what you want to try first of all)
again, I'm a newbie too when it comes to Mental Ray, this is just the information I've gathered over the last 24 hours. I'm actually just doing some tests to set my mind straight on what setting does what, so i'm doing loads of test renders with different settings. Seems to be making things a bit clearer in my mind.
But from what I have been told, the trick to that sort of lighting is to use an object as a light source, and then use final gathering.
(or, if you're not using final gathering that might be what you want to try first of all)
again, I'm a newbie too when it comes to Mental Ray, this is just the information I've gathered over the last 24 hours. I'm actually just doing some tests to set my mind straight on what setting does what, so i'm doing loads of test renders with different settings. Seems to be making things a bit clearer in my mind.
Raptor235
10-08-2002, 01:20 PM
how do u use an object as a light?
Carina
10-08-2002, 01:29 PM
Well final gathering is all about colour bleeding (as far as i understand), and thus if you use a very bright object you should be able to use it as a lightsource...
Again, I am just the messenger... don't kill me if I'm wrong;)
Again, I am just the messenger... don't kill me if I'm wrong;)
-wT-
10-08-2002, 02:00 PM
Well... damn it, ok I'll post it :)
Although I'm still somewhat proud of it, but I guess you people can have it. If it's helpfull, maybe a simple thanks would be reasonable, don't you agree? :beer:
So, a few words about the scene. Besides the right settings I've acquired trough try-fail mehtod, it has this huge box with scaled up and open top and smoothed normals, in center of the scene. This is there for two things:
1. To catch shadows. (And the material has it's alpha set to black, so you can composite your model easily)
2. To also catch the nice light blue color, which otherwise would be rather dark if you used i.e. just a plane with usebackground as the material.
This box has one slight disadwantage though. Because the box affects the illumination of the enviroment, it can't be very tall (As then it would look like the light would come from a small hole in the sky on top of the model), and this leads to the fact that you will get a few cm's of dark blue background you have to fix up with photoshop. But don't worry, I've done it to that picture I attached too (Along with several other images I've rendered in the same way), and the background got halfway behind his head, but as you can see it's not very easy to notice after a few mins of playing around with photoshop. Other problem is that because there's a spotlight "sun" in the scene, which illuminates the box (AKA enviroment), there will be a darker spot behind the spotlight. But this isn't a big issue either, as I've fixed it with another spotlight which only illuminates it, but there will still be a small line for you to fix in PS, but nothing too dramatical.
So, besides those, the only thing changed was the spotlight settings, camera enviroment and the MR settings itself. Have a look at those to understand how I did it all.
To control the speed and quality of the renderings, the two main things to change are:
1. The spotlights arealight samples, to get rid of shadow graininess.
2. The min and max distance of FG. The lower the number, the better results and more slow renders you get. The raycount is good at where it is now, you may want to experiment with it if you want, but the distance is the setting that affects the quality/rendertime most.
So, with this I rendered "Geroge" in 10mins, with AMD TB 1.4GHz. Have fun! :thumbsup:
Although I'm still somewhat proud of it, but I guess you people can have it. If it's helpfull, maybe a simple thanks would be reasonable, don't you agree? :beer:
So, a few words about the scene. Besides the right settings I've acquired trough try-fail mehtod, it has this huge box with scaled up and open top and smoothed normals, in center of the scene. This is there for two things:
1. To catch shadows. (And the material has it's alpha set to black, so you can composite your model easily)
2. To also catch the nice light blue color, which otherwise would be rather dark if you used i.e. just a plane with usebackground as the material.
This box has one slight disadwantage though. Because the box affects the illumination of the enviroment, it can't be very tall (As then it would look like the light would come from a small hole in the sky on top of the model), and this leads to the fact that you will get a few cm's of dark blue background you have to fix up with photoshop. But don't worry, I've done it to that picture I attached too (Along with several other images I've rendered in the same way), and the background got halfway behind his head, but as you can see it's not very easy to notice after a few mins of playing around with photoshop. Other problem is that because there's a spotlight "sun" in the scene, which illuminates the box (AKA enviroment), there will be a darker spot behind the spotlight. But this isn't a big issue either, as I've fixed it with another spotlight which only illuminates it, but there will still be a small line for you to fix in PS, but nothing too dramatical.
So, besides those, the only thing changed was the spotlight settings, camera enviroment and the MR settings itself. Have a look at those to understand how I did it all.
To control the speed and quality of the renderings, the two main things to change are:
1. The spotlights arealight samples, to get rid of shadow graininess.
2. The min and max distance of FG. The lower the number, the better results and more slow renders you get. The raycount is good at where it is now, you may want to experiment with it if you want, but the distance is the setting that affects the quality/rendertime most.
So, with this I rendered "Geroge" in 10mins, with AMD TB 1.4GHz. Have fun! :thumbsup:
DesignDawg
10-08-2002, 02:03 PM
OK, guys,
Doing the "Brazil-looking" shadowy cool renders in MR is easy, but it's not just a matter of checking on the boxes and letting it roll.
Here's what you do:
Create a sphere (or dome....either way you want to work it.) with a radius of BIG (like 1000 or 10000, whatever.)
Assign a ramp or solid color (ramp works better with brightness falling off as you go down) to the sphere's shader in the incandescense channel. --Or, you can just use a surface shader, but I think a lambert with no diffuse, no color, just incand. works better. Experiment.
Now, you have your sky dome to cast light with. Now you need something to CAST photons that will bounce around and give you light. Create a point light, but turn its intensity down to 0. You don't want any light from this light. Just photons.
Now, in your MR Render Globals, set render quality to production. Now, go into the "Production" tab and turn on final gather. You may want to experiment at some point with the min and max radius settins, but the optimized settings elude me right now.... Anyway, this will get you started.
Now, your point light with emit photons which will reflect off the dome or sphere you've created, and you'll be lighting your scene with a sky-shaped ramp of color, and BOY OH BOY, will it be pretty. :) You may need to tweak your ramp after you get started. BTW, once the photon maps has been generated, as long as you don't change it or force it to rebuild every time, subsequent renders will go QUITE fast as you tweak colors, intensity, etc...
And to do REAL HDRI with MR, simply convert your HDR light probe files into floating point TIFFs or MAP files with HDRShop, and use them in place of the ramp in the incandescense channel (with an environment sphere, of course, to get them "unwrapped" properly.) Now, you'll be using the HDR light probe to light your image, and you'll get the reflections, too. You can also, if you prefer, in either case, turn off the primary visibility of your environment sphere, and it will still light your scene.
To adjust the exposure of the HDR files, use the value slider in the color gain of your image. 1 is 100%. 2 is 200%, etc... THis slider DOES act as a true exposure slider for true HDR images.
HAVE FUN! --And post renders.
Ricky
Doing the "Brazil-looking" shadowy cool renders in MR is easy, but it's not just a matter of checking on the boxes and letting it roll.
Here's what you do:
Create a sphere (or dome....either way you want to work it.) with a radius of BIG (like 1000 or 10000, whatever.)
Assign a ramp or solid color (ramp works better with brightness falling off as you go down) to the sphere's shader in the incandescense channel. --Or, you can just use a surface shader, but I think a lambert with no diffuse, no color, just incand. works better. Experiment.
Now, you have your sky dome to cast light with. Now you need something to CAST photons that will bounce around and give you light. Create a point light, but turn its intensity down to 0. You don't want any light from this light. Just photons.
Now, in your MR Render Globals, set render quality to production. Now, go into the "Production" tab and turn on final gather. You may want to experiment at some point with the min and max radius settins, but the optimized settings elude me right now.... Anyway, this will get you started.
Now, your point light with emit photons which will reflect off the dome or sphere you've created, and you'll be lighting your scene with a sky-shaped ramp of color, and BOY OH BOY, will it be pretty. :) You may need to tweak your ramp after you get started. BTW, once the photon maps has been generated, as long as you don't change it or force it to rebuild every time, subsequent renders will go QUITE fast as you tweak colors, intensity, etc...
And to do REAL HDRI with MR, simply convert your HDR light probe files into floating point TIFFs or MAP files with HDRShop, and use them in place of the ramp in the incandescense channel (with an environment sphere, of course, to get them "unwrapped" properly.) Now, you'll be using the HDR light probe to light your image, and you'll get the reflections, too. You can also, if you prefer, in either case, turn off the primary visibility of your environment sphere, and it will still light your scene.
To adjust the exposure of the HDR files, use the value slider in the color gain of your image. 1 is 100%. 2 is 200%, etc... THis slider DOES act as a true exposure slider for true HDR images.
HAVE FUN! --And post renders.
Ricky
Raptor235
10-19-2002, 03:28 AM
Hey wt I took your setup and I changed it a bit I put a cylinder there instead of the square I just though it might be better, anyway here is a img I rendered but something is screwed up it takes FOREVER it took the whole night to render on my xp1900 512 ram I'm not sure what's wrong though any ideas?
graphiouz
10-19-2002, 12:27 PM
hehe, i had to try render like -wT- (MrToMaya1.5)
all is set to default FG in MrGlobals (1000,0,0), exept the lambertShader little adjustment on that,, perspCam is set to lightWhite, point Light (0)
no shadows, It took 25 sec to render it!
http://hem.bredband.net/b122388/misc/grim_wire.jpg
all is set to default FG in MrGlobals (1000,0,0), exept the lambertShader little adjustment on that,, perspCam is set to lightWhite, point Light (0)
no shadows, It took 25 sec to render it!
http://hem.bredband.net/b122388/misc/grim_wire.jpg
-wT-
10-19-2002, 04:01 PM
Raptor235: Did you try the scene without changing anything? Maybe the settings are somehow different in 1.5, as that scene is for 1.0. Could you post the spotlight's MR settings, and the FG settings from the MR Globals here?
graphiouz: That's cool, but remember that I used a spotlight as arealight, and good FG settings. That's why it took 20mins, if you would add a spotlight or such into your scene, you'd see a definite quality problems with the shadows with those FG settings.
But the rendering is cool anyways :thumbsup:
graphiouz: That's cool, but remember that I used a spotlight as arealight, and good FG settings. That's why it took 20mins, if you would add a spotlight or such into your scene, you'd see a definite quality problems with the shadows with those FG settings.
But the rendering is cool anyways :thumbsup:
mushroomgod
10-19-2002, 07:14 PM
incase anyone doesent know...you dont need to create a sphire/cube for your object to occupy, just change the colour of the enviroment in your camera settings.
fango
10-19-2002, 07:56 PM
thanks designdawg for the quick mini tutorial :) !
here s a 6 mn render on 1gh 512 using desindawg step by step
http://wits.free.fr/testray.jpg
mushroom , i thought you needed the sphere/cube as an environment for the photons ? maybe there s something i m not getting right.
here s a 6 mn render on 1gh 512 using desindawg step by step
http://wits.free.fr/testray.jpg
mushroom , i thought you needed the sphere/cube as an environment for the photons ? maybe there s something i m not getting right.
Raptor235
10-19-2002, 08:00 PM
I'll post all my settings a little bit later on, just a quick note on my scene it renders really fast when I hide the complicated parts of my character such as arms and feet. THen it renders in like 1 minute but when all those small objects come into to play it goes up to hours...
-wT-
10-19-2002, 09:44 PM
Ah, well then it may be just that what's causing the slowdown. The FG settings are quite tight, so with small details it seems to behave like that... Hmmm, haven't concidered that, haven't rendered anything with relatively small detail with that setup before...
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