Very good resource and advice, thank you Joseph! On Jun 24, 2014, at 9:13 AM, "Ponthieux, Joseph G. (LARC-E1A)[LITES]" <[email protected]> wrote:
> The problem is that you are using Hubble images. Hubble images are high res > and beautiful but often are only representative of a single focal point in > space. What you want is a "star map" that is a cylindrical projection suited > for your sphere. You will find the maps you need at this link. In particular > the high res Tycho maps are probably what you want. > > http://svs.gsfc.nasa.gov/vis/a000000/a003500/a003572/ > > When you map these onto your sphere you will notice that the center of your > sphere of the focal point of a "disc" or "ring" of stars. You'll see the > "ring" form on the inner side of the sphere. There were three maps > historically, Tycho, Hipparcos, and Yale. The following links contain them > but these do not look like the highest res versions. > > http://www.nasa.gov/multimedia/3d_resources/assets/tycho8.html > > http://www.nasa.gov/multimedia/3d_resources/assets/hipp8.html > > http://www.nasa.gov/multimedia/3d_resources/assets/yale8.html > > > Each was created at different resolutions and star counts. One is synthetic I > think, and that I believe is the Yale map based upon the Tycho catalog. The > map is of higher contrast and may lack a lot of the intermediate or > diminished stars so it may be useful in some circumstances. You'll have to > figure out what the basic appearance is that you are looking for and a > combination of the maps may be what you want. As you probably have already > discovered, you won't be able to let your camera get too close to the texture > surface as the stars will become abnormally large and the illusion will be > lost. Its best if you scale the sphere as large as you can and keep the > surface as far from the camera as possible to reach the effect you want. > > If you want a moving starfield, the best way to achieve that is generate a > massive field of small triangles set to constant white. The distance apart, > size, and randomness will have to be worked out. You can do this as particles > as well, but if the particles are set to pixel height you'll lose the sense > of perspective and distance as you fly through them. > > -- > Joey Ponthieux > LaRC Information Technology Enhanced Services (LITES) > Mymic Technical Services > NASA Langley Research Center > __________________________________________________ > Opinions stated here-in are strictly those of the author and do not > represent the opinions of NASA or any other party. > >> -----Original Message----- >> From: [email protected] [mailto:softimage- >> [email protected]] On Behalf Of Nancy Jacobs >> Sent: Monday, June 23, 2014 5:43 PM >> To: Softimage Listserve >> Subject: Ideas for star fields? >> >> Hello, >> >> I'm needing a star field kind of background for a scene, and looking for >> ideas >> to create it. I have been using Hubble images wrapped around a sphere, >> around the scene, but I'm finding it doesn't read well, even with very high- >> res Hubble images. >> >> So, I'm wondering about other ways to create star fields. Has to be 360 >> degrees, seamlessly -- and I don't have the capability to deal with that in a >> compositing situation. >> >> So....any ideas? >> >> Thanks, >> Nancy >
