PDA

View Full Version : How to Create a Planetarium Camera



B_Free
11-14-2007, 01:24 PM
I'm trying to create content for a planetarium full-dome projection system, but I'm not sure how to get a Camera in Lightwave to render images such that they'll look right in the theater.

Here's a quick into to how the Planetarium system is setup:
A projector essentially takes a 1024 x 1280 pixel image and projects it up into a hemi-spherical dome.

The image isn't simply projected up though, it's projected around. Here's an image to demonstrate what I mean.
http://www.bradfreese.com/Images/WebViewing/DomePixelDimensions_Small.jpg

Each of the circles in this image are the same number of degrees away from each other.

Now here's my quick setup in Lightwave:
http://www.bradfreese.com/Images/WebViewing/LW_CameraSetup.jpg

This dome model has 9 lines of latitude, just like the coordinates in the image above.

If my camera is setup correctly, when viewing through it, each of those circular lines of latitude should be the same distance apart from each other.

But here's what it looks like when I'm zoomed out:
http://www.bradfreese.com/Images/WebViewing/LWCamera_ZoomOut.jpg

As you can see, the circles get closer as you move towards the center.

Does anybody have any ideas/suggestions on how I could "correct" for this distortion?

Lightwolf
11-14-2007, 01:48 PM
Try the advanced camera, probably with a cylindrical horizontal FoV of 360, and a vertical one of 90 or something like that.
You're also not likely to get a proper preview in openGL, you'll need to render to check the camera.

Cheers,
Mike

jameswillmott
11-14-2007, 04:28 PM
you'll need to render to check the camera.

Or preview it with FPrime if you have it.

3danim8d
11-14-2007, 05:00 PM
B_Free,

The typical process for this is to render out a series of 90 degree FOV cameras and use Stitching software to warp the resulting images into a Dome Master for the presentation.

Do you know which system the planetarium you are going to be showing on uses?


Jeff

Roly
11-14-2007, 05:36 PM
...or you should try this settings. See attach image.

B_Free
11-14-2007, 06:01 PM
Yeah, the planetarium is currently in the process of ordering a Konica Minolta Mediaglobe II.

I'm volunteering there and I'd like to make some animations that they can play in the theater once they get it. The device runs off media on a DVD-ROM so I'm hoping that there won't be any proprietary formats for it.

I'm sure you know more about this than I do. Do you know if they have anything that would prevent me from authoring content?

Thank You!

B_Free
11-14-2007, 06:06 PM
ROCK ON!!!! :)

That's exactly what I just tried! My render is below.
http://www.bradfreese.com/Images/WebViewing/LW_Camera_Exp_1_Small.jpg

:beerchug:
Great minds think alike!

Now I'll try projecting it back into a dome, just to double check. :)

Thank You very much!!! You guys are AWESOME!!!