Camera Projection - Nuke 101: Professional Compositing and Visual Effects - page 471

1. Read in the SkyDome.png image from the chapter11 directory ( FIGURE 11.22 ).
Figure 11.22. The sky texture you will use.
2. Make sure proxy mode is off.
Look at the bottom-right corner in the Viewer. It says square_2k. This is a format
defined in Nuke by default, which is why the name is displayed here instead of
as a set of two numbers. The format means this is a 2048×2048 image. It's a mir-
ror ball map, which is one way of transforming a spherical image into a flat im-
age—taking a photo of the reflection of half a chrome-painted ball. To place the
image on a sphere geometry, you need to turn it into a lat long map—a flat rep-
resentation ofthesphereasitisbeingunraveled. TheSphericalTransformnodeis
used to transform between several different ways of displaying spherical shapes
in a flat image.
3. Select Read2 and insert a SphericalTransform node after it from the Transform
Toolbar.
SphericalTransform's default is exactly this—changing from a Mirror Ball input
to a Lat Long Map output. You just need to change the resolution. You can look
atasphereasanobjectthatistwiceasroundasitistall(360degreesaround,180
degreesinheight).Andsotheresolutionofthetextureshouldbetwiceaswideas
it is tall. You'll need to change the Output Format property.
4. Change the Output Format resolution by selecting New from the drop-down
menu and then creating a format called 2:1 with a resolution of 2048×1024
( FIGURE 11.23 ) .