(For an improved version of this star globe, please see Background Stars v2.)
Do you need night sky stars with accurate magnitudes and a good looking milky way for the background of your whole Maya scene? Do you want 360 degrees of coverage without any stitch marks, seams, or pole pinching? Well here is what I call the ‘star globe’. (Named out of ease for communicating with my team.)
Just import it, point-constrain it to your camera, and scale the star globe to surround your entire scene. This insures that the star globe will follow the cameras position but not its rotation. For a final render, we typically use preview quality settings and don’t have any aliasing/blinking of the stars. Fisheye camera typically at 500 focal length to shortcut the grey blurry line problem, but it depends how big you’ve scaled the star globe (you’ll know easily if the stars look blurry and weird).
Also, make sure to check the light linking of the star globe so that there are no lights attached. This is because the star globe material has the texture set to incandescence. This insures that it will look always look the same without having to worry about other light sources accidentally brightening the stars.
maya scene (using mental ray) – star globe
These stars are optimized to look like pinpoints of light on specifically a dome. But if your final screen is instead flat, well the stars might appear more like spheres of light. In this case I would suggest lowering the camera focal length. Therefore more stars will be in the shot and they will appear smaller. And if you don’t want to change the focal length for your shot, then create a render layer override instead.
The stars were originally rendered in Sky-Skan’s DigitalSky software. PTgui was then used to re-project the night sky images from circular fisheye to equirectangular (what I call ‘defishing’); this was needed for easy UV mapping of a sphere in Maya. We spent alot of time in the dome to optimize the look of the star pinpoints, color saturation, and halo size. So we now use these stars for all of our fulldome productions. Please remember that everyone has different standards of what a star background should look like and this matches our criteria after much discussion about what we liked and didn’t like from other fulldome shows. What looks great on a computer screen does not often transfer to the dome in same way; this was created to look crisp in the dome.
Note: If your renders are starting up slowly, then use Photoshop to convert each of the star globe source images into IFF’s (type: maya, not amiga). Then point the Maya texture nodes to the IFF’s instead. The reason for this is that IFF’s are memory mapped; meaning Maya will only load into memory the parts of the image that it actually needs to render. If you want even faster renders, convert the textures into Mental Ray MAP files.