|
HDRI: High Dynamic Range Image
This tutorial will show you how to use HDRI images to make
realistic environments and lighting.
HDRI images are called High Dynamic Range Images because
they have a high-range that can simulate different amounts of light.
Normal images can have lighting from 0 (black) to 255 (white). HDRI
images can have a much higher range since it stores values differently.
The main format of HDRI images are Radiance *.hdr files. Now, 3ds max
6 can use HDRI images without third-party plug-ins.
What you need for this tutorial:
First of all, we'll need to modify the HDR image we
downloaded a little. If you'll notice, it's in kind of a ball shape
because it was taken with a light probe. We want it in a rectangle
shape. So... Open up HDR Shop and go to open and open
up the .hdr file you downloaded (you might have to unzip it):
Unzoom or whatever and it will look somewhat like this.
We want it to be a rectangular map. So... go to Image > Panorama >
Panoramic Transformations. The program can convert it into a
rectangle.
You'll end up with something like this:
Save it. I just saved it with the same name in my
3dsmax\maps\Reflections\ folder.
Now, open Max.
To get started, we'll make a simple sphere to test with:
Open up your Material Editor (M). We'll make it real shiny, so
make a new Raytrace material and set the Reflection to 100.
Now for the environment. Go to Rendering > Environment and
proceed to put the HDRI file in the Environment slot. It'll pop up
with a line graph and some lines and stuff. Just accept. That's
for adjusting the maximum brightness areas and black areas.
But there's a problem. If you render a few viewpoints, the environment
won't look right. It'll follow the camera. Instead of being an
all-around environment it's just like a background image, and you don't see
your sphere. The problem is with
its mapping coordinates. We will fix this.
Open up the Material Editor but keep the Environment dialog open. Now
drag the map in the Environment map slot into an empty box in the Material
Editor. Make sure you choose Instance and not Copy, so that they'll
stay linked.
 Now, with change the
Mapping Coordinates from Screen (wherever you're facing) to Cylindrical
Environment (A cylinder around you). You could also try Spherical.
 Now, when you render it
will produce some nice results. The end result is that your sphere
looks like it's floating in the forest, since all the lights are exactly the
same.
Click to download a 640x320 PNG image
Back to Tutorials |
