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: softimage-boun...@listproc.autodesk.com [mailto:softimage-
> boun...@listproc.autodesk.com] 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

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