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lomc89
08-27-2006, 05:32 PM
How do you make partigon stars look more like fuzzy points of light instead of... POINTS? Every space scene I've attempted clearly looks fake because of it; like badly-colored confetti spread across black linoleum.

Axis3d
08-28-2006, 06:18 PM
You could render your partigons as a separate pass, then composite them into your scene later (blurring them in the process).

Or, if you wanted to do it all in Lightwave, you could add a regular emitter, then apply Hypervoxels to them using sprites. The sprite can be a soft disc graphic that you can make yourself or just mess with the Hypervoxel settings themselves.

ShawnStovall
08-30-2006, 08:19 PM
If you have LW 9 you could use Pixie Dust.

jameswillmott
08-30-2006, 08:33 PM
Pixie Dust works well, if it's a backdrop you want, try a Textured Environment using Crust, 20mm for the scale and coverage of about 0.1 and set colour to white.

starbase1
09-07-2006, 07:14 AM
Hyperstars is an excellent value plugin, and works very well. IOptions of accurate or randon positions.

For still images I have some free high res backdrops you can grab...
Nick

Darth Mole
09-17-2006, 07:30 AM
Definitely recommend Hyperstars. If you do space scenes regularly, it's a really cool plug-in. Dead easy to use, too. Check out the examples.

http://www.ficatech.com/

lwaddict
09-17-2006, 08:48 PM
Or you could use Digital Confusion or Depth of Field...the way we do it...
then, pretty much everything 1 kilometer out blurrs the way they should.

Note: Even space dust and debris look better using this trick.

Andyjaggy
09-20-2006, 10:48 PM
Using som DOF usually works really well for giving the stars a slightly softer look.

avkills
09-26-2006, 09:55 AM
Just bought Hyperstars and yes it is a lot easier than trying to use single point polygons or Pixie Dust or anything else.

Best of all it works in all camera modes.

-mark

Andyjaggy
09-26-2006, 01:05 PM
I just checkout out the hyperstar plugin and it does look really cool. Next time I do a space scene I will have to consider buying it.

byte_fx
10-11-2006, 06:19 PM
Another way that I've used is to place a basic distant light at a far distance and aimed at the camera.

Turn off affecting all objects, etc.

Apply a volumetric with a fractal pattern squished on the Z dimension - about 5-10% of the X and Y dimension for starters.

Tweak the Lucanity, etc. for the needed appearance.

byte_fx

Dave Jerrard
10-12-2006, 10:34 AM
With Partigons and SPPs, make them luminous, but 0% diffuse. I'd also make them with Additive Transparency. This way, they work well with stuff like nebulae or anything else they might pass in front of without looking like darker dots.

Also, to make variations in brightness, don't use Lumnosity - use Particle Size/Line Thickness and make multiple layers or objects for different star magnitudes. Here's an example of a starfield I did several years ago using these techniques and a photo I took of that same area of the sky.

http://tinyurl.com/yg6z3k

http://tinyurl.com/yjo8ko


He Who Thinks These Are Pretty Darned Close.

starbase1
10-12-2006, 02:52 PM
As someone who studied astronomy at university, I'm rather impressed!

The main things I would suggest are:

1. The fainter stars are too bright, and should be on the limit of visibility

2. The colours are too strong for naked eye appearance, (though I note the spectral types appear correct!), particularly the blues.

(Mind you, colour balance of astronomical objects is notoriously subjective).

How do they look with motion blur?

I did something very roughly equivalent in Povray many years ago - the other advantage of additive I learned doing that is that it makes multiple stars look a LOT better. Otherwise double stars too close to separate come out too faint. What catalogue did you use?

Nick.

(He who would pay for the files if they popped up on Renderosity!)

Dave Jerrard
10-12-2006, 03:31 PM
As someone who studied astronomy at university, I'm rather impressed!Thanks. I'm more of a hobbyist, or backyard astronomer myself.





1. The fainter stars are too bright, and should be on the limit of visibilityWell, I didn't have the best source material to go by, and I didn't spend any serious amount of time on this. I whipped up a solution a few years back for a movie (Interceptor Force 2) that had a long space sequence.




2. The colours are too strong for naked eye appearance, (though I note the spectral types appear correct!), particularly the blues.

(Mind you, colour balance of astronomical objects is notoriously subjective).Yep. When I rendered that image, I was going for the same look I had in the photograph, which was about a 20 second exposure. If I can get that color balance close, then it's easy enough to get the more desaturated look (which I also have a photograph of).



How do they look with motion blur?They're particles, so you really need Particle Blur turned on. They break up like crazy without it. Unfortunately, the method LW uses for this results in an inaccurate brightening of the stars as they streak, where they should actually dim. But since these are objects, it's easy enough to dissolve them to simulate this effect. Maybe the new motion blur will take care of this automatically in the next release.


What catalogue did you use?Ummm. Would you believe ActualStars.lwo? :o I just took that, split it into multiple layers, one layer per magnitude, and then added a couple layers of random points to fill in for the fainter stars. For certain stars, like those in Orion, I actually went in and applied colors by hand. To finish it off, I added a few nebula panels here & there.

Now that I do most of my rendering with the new cameras, I need to find another way of doing these. That is, until NewTek gets points and edges to render in the new cameras. So far, I've tried both Pixie Dust and HV Sprites with half decent results, but they do tend to take a bit longer to render.



(He who would pay for the files if they popped up on Renderosity!)


He WHo Has These Kicking Around Somewhere...

starbase1
10-13-2006, 12:54 AM
I did an LW star field way back in LW5.6 (I think) using a cuple of thousand small lens flares! They blurred OK...

I also prebviously managed to get the Yale bright star catalogue into LW, and that has spectral types in, whoch should make it possile to colour automatically. Let me know ifyou have another crack at it, I may be able to help.

Nick

Dave Jerrard
10-13-2006, 01:28 PM
I did an LW star field way back in LW5.6 (I think) using a cuple of thousand small lens flares! They blurred OK...

I also prebviously managed to get the Yale bright star catalogue into LW, and that has spectral types in, whoch should make it possile to colour automatically. Let me know ifyou have another crack at it, I may be able to help.

Nick
I think my record for lens flares in a scene was 340, used in a logo. Back then (the Amiga days), just rendering that many lens flares would take over 45 minutes alone. Ouch. Since then, I've used small lens flares mapped onto Sprites for stuff like stars or distant/small lights, which render much faster than flares, and don't eat up so many lights. I've also done a few starfield tests using the flare-sprite method, and they look pretty good...

37823

It's a bit of a trick to get the right color & brightness for each one though, without needing to break the starfield particles into multitudes of layers. I suppose a couple weightmaps could be used to define the color & intensity of each particles, and then accessed through gradients in the HV panels to adjust the size, luminosity and colors of the Sprites. This might even work with Pixie Dust. The only problem I see with this would be how the stars blur. Tiny details don't tend to blur very well, though the upcoming new blur might fix this.


He Who Thinks He Just Found A Few Bugs In This Area With The New Cameras.

lomc89
11-11-2006, 12:21 PM
I just bought Hyperstars, but omg, I can't find where you apply an image filter! Not to mention I could never figure out how to do the depth of field... *I stoopud*

starbase1
11-11-2006, 12:27 PM
image processing tab.

Puguglybonehead
11-12-2006, 01:39 PM
I bought Hyperstars a while ago and I'm very happy with the results. Easy to use and renders fast and perfect. Motion blur works well with it and never any of the flickering in animations that you tend to get with partigons or background textures. Looks good even with really low antialiasing. It also seems to handle background images (for nebulae and whatnot) better than Textured Background or Image World does.