Hey
everyone....I received a lot of comments about the render on my baseball
shot so I put together a little tutorial on how to do it.
My
little disclaimer up front....This is an easy way to get a nice bounced
light effect in your renders plus some really nice occlusion....I am not
a MR expert, If anyone is a MR expert and would like to add suggestions
feel free!
Ok,
so here goes.

IBL
for Animators
IBL
stands for Image Based Lighting...its an option when rendering with Mental
Ray. I'm going to share with you my MR(Mental Ray) settings and the steps
I took to light my shot. First I use this method because A.
I like the results B. I'm not a lighter but I still want
my shots to look good and C. I don't like spending a
lot of time stetting up lights, but I do have time for it to render over
night. WARNING: MR renders can take a loooong time.
First
thing you will have to do is change all of the shaders on Bishop. His
default shaders are old and do not work in MR. If you leave them you'll
have a glowing Bishop. Next when swapping shaders(I won't go into that
here) make sure to turn reflectivity off. For his head and body I used
lambert and the eyes are phong.
So
here is our Maya scene all ready to go....Click on the images to see them
larger.

This
is what the shot would look like if we just hit render.

Now
lets setup MR. Open your Render Globals and choose Render Using: mental
ray. You will see a new tab appear named mental ray. First I set the Quality
Presets to: production. After that I change values and that will change
to read custom, but its a great way to start...it does some of the work
for you.
These
are the settings and values that you will change:
Anti-aliasing
Quality
-Number of Samples
--Min 0
--Max 2
-Multi-Pixel Filtering
--Mitchell
--Width 4
--Height 4
-Contrast Threshold
--All 0.1
-Sample Options
--Sample Lock
Ray
tracing
-Reflections 10
-Refractions 10
-Max Depth 20
-Shadow Depth 2
-Scanline On
-Faces Both
Shadows
-Method Segments
-Maps on
-Rebuild Off
-Bias 0
You
will also see these settings in the image above.
Now
expand Final Gather and check the box to turn it on.

Final
Gather
-FG Rays 500
-Min 0
-Max 0
-Filter 3
-Falloff Start 0
-Falloff Stop 0
-Trace Depth 2
-Trace Reflect 1
-Trace Refract 1
-Secondary Diffuse Bounces
Thats
it! Now for the IBL. Expand Image Based Lighting and click create.

Now
you will see a huge sphere in your maya scene....if your sphere comes
in too large and you can't see it, zoom out till you can and scale it
down till it is just a bit larger then your scene.

Now
lets see what IBL is all about. Select the sphere and open up its attributes.
Change Type to Texture. Change the Texture color to white. Your render
will look like this. Lots of bounce white light throughout the scene.

What
Final Gather does is shoot light rays into your scene and they bounce
around. If you look closely you will see the blue on his jeans also bouncing
onto his arms and the bleachers. Also a very nice feature with MR is the
ambient occlusion. Really simply...you will get nice dark areas where
geometry is close to each other...in this render you will notice it the
most where his butt touches the bleachers.
To
further illustrate this point of bounced light, change the white to red.
Now your render will look like this.

Now
set it to 50% gray. Thats a really good starting point and as you can
see by this render, that looks pretty good.

You
can get away with a clean simple look just by adjusting the color and
adding one or two lights. The point is to not muddy up a scene. The characters
look simple, the lighting and sets should match.
IBL
stands for "Image" Based Lighting right...so what about an image.
Well thats what we are going to do next. I knew I wanted some bounced
green light from the grass below him and some bounced blue light from
the sky above him. So I found a photo that had those elements and adjusted
it in PhotoShop to look like this.

As
you can see it doesn't look much like a photo anymore....these will be
wrapped on the sphere so its important to make sure you get the colors
in the correct spots. I start with a photo, or a painting of mine, rather
then using a ramp because you can get more color variation within your
major colors. Also it takes time in this step to get the saturation and
color just right.
To
add a file just select the sphere. Change Type to Image File and click
the folder button next to Image Name to link to the file. I should mention
its very important to create maya project files. You should store your
images in the sourceimages directory. Now the render looks like this.

Ok
so that is looking about how I want it...now to add detail. How do we
do that? Lights!!
The
final render has only two lights...the IBL gives you so much that you
really only need one light to act as a source(such as the sun) and to
cast shadows.
My
audio has some birds chirping in it so I thought that there should be
trees around. I decided to add what I call a Canopy light. Its just a
light that has an image mask on it to give the appearance of light coming
through a tree. I start by creating a spot light. I select the light and
then choose Panel - Look Through Selected. That way I can position the
light by looking though it like a camera.

Next
I open the lights attributes. First I select the box next to Color. A
new window will open up and I select file.

Then
I select the folder button next to Image Name. A new window will open
and I select my canopy image.

My
canopy image looks like this. The file works best in gray scale.

Now
lets change the lights attributes. I set my Decay Rate to Quadratic...it
has a shorter fall off and I like a nice hot spot. After you change that,
turn on Raytrace Shadows under Shadows. Last but not least is to adjust
your Intensity. Intensity is very different with Quadratic Decay so you
will set this value much higher then your probably used to. This will
be some back and forth, rendering out to test as you go. As you can see
my Intensity for this light is set to 11000.000. You can see the result
in the render below.

Now
this scene feels like there is more to it off camera and we are starting
to get some mood. The only thing I don't like is his face is too dark...Time
to add one last light.
For
just a beauty light I chose a point. Similar settings as before, Quadratic
decay...but this time no shadows and no image file. As you can see below
I set my Intensity to 33.000, I just want this to be a subtle soft light
on his face. Also I like to adjust the placement of the light by hitting
7 in maya so I can see a rough estimate of the results.

The
render looks like this.

Alright,
just how I wanted...now its time to render and composite....but one last
thing before I do that. Turn off Primary Viability on the IBL. Select
the IBL sphere, open its attributes. Under Render Stats un-check Primary
Visibility. This will give you a nice clean alpha for your composite.

I
rendered my shot out and composited it in Adobe After Effects. Two layers....my
render and a background image I created in PhotoShop. I took a photo of
a baseball field and blurred it out and adjusted the color. I also added
a shadow of our fake tree. You can see my PhotoShop layers below.

So
thats it!! This is my first tutorial so if anything needs clarification
just let me know. If anyone would like me to go further in depth on shading,
compositing, or any other area that I left out in in this tutorial I'd
be more then happy to write more. Please, comments and suggestions are
very appreciated. Remember we are not here at AM to be great lighters,
don't spend homework time on this....If you really like it, on our summer
break, if you need a rest from animating, mess with it then. I'd start
with a simple scene with a sphere on a plane.
If
you would like to see more examples of this check out my demo reel. All
the renders were done with this exact same method.
Enjoy!
-Stephen
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