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DaveD
12-13-2007, 03:36 PM
I'm trying to create the typical, glowing, blue atmosphere effect as seen on many planetary images. Similar to the following:

http://www.imagico.de/pov/pict/atmosphere_tst1.jpg

Notice the blue glow only affects the outline of the overall planet and doesn't obscure the details in the foreground. Otherwise simply using the luminance and glow channels on another sphere "wrapper" would probably suffice. And insight on how this effect could be recreated using 9.6 would be appreciated. No plug-ins please, I'm hoping clever use of procedurals is my answer. Thanks!

NWoolridge
12-13-2007, 04:27 PM
One effective approach is to use a visible light, centred on the planets' axis, and its visibility and falloff values adjusted appropriately; it renders fast, too.

Nick

DaveD
12-13-2007, 04:39 PM
Wouldn't the visible light also color the foreground? I'd like to isolate the effect to the outer edges mostly. I suppose I could do this with wrapping a half sphere around a full sphere but it would be clunky for animation and always aligning to the camera view. Perhaps some sort of falloff or fresnel effect?

NWoolridge
12-13-2007, 04:53 PM
Try it; the way visible lights work, it does what you want. Here's a quickly slapped together sample file...

Nick

DaveD
12-13-2007, 04:58 PM
Thanks but I'm still using 9.6. Maybe a screenshot of the light dialog box? Thanks for your help with this.

NWoolridge
12-13-2007, 05:11 PM
Oh bugger... sorry! You mentioned you were using 9.6 too...

Here's a screen shot

Nick

DaveD
12-13-2007, 05:21 PM
Excellent! Thanks for your help. I was hoping there was a simple solution and I was just thinking too hard.

kromekat
12-13-2007, 07:45 PM
A bit of blue fresnel layered in the colour channel really helps to make a believeable atmosphere, since as the horizon falls away, there is an increase in atmosphere density.

http://www.kromekat.nildram.co.uk/stuff/planets.jpg

DaveD
12-13-2007, 11:15 PM
Ooooo...that's nice too. And that method would allow for areas of the planet to remain in the shadows as in your examples. I see there are probably a few ways to accomplish this. I'll have to do some more experiments to see which works best for my application. I was experimenting with Nick's method a little and noticed adding some wavy turbulence noise to the light creates a nice cloud-like effect also. Thanks for the input!

kromekat
12-14-2007, 12:31 AM
Your welcome - I did in fact use the visible light in those too to add the halo, but it's less obvious than on the other example provided!

Adam :)

DaveD
12-14-2007, 02:25 PM
I just had a quick look around your site, Adam. Fantastic, fun stuff. Do you have any of your tutorials posted anyplace online? I'd love to pick up a few more pointers on creating some fun stuff like that.

As for your planets, I'm assuming you're using really hi-res satellite images of some kind for those clouds and terrains?

kromekat
12-14-2007, 02:47 PM
Dave,

Thanks :)

You can get a lot of the tutorials via the Computer Arts site/3D World, or Imagine FX as pdfs :)

Yeah the clouds were from a Nasa site, but the planet in this example is purely procedural noises. In other examples, I have used a combination of high res Nasa photos, hand painting and manipulation along with procedural shaders.

Adam :)

sismik
12-14-2007, 04:49 PM
Hi

here is the link to a great tutorial for creating a realistic earth

http://www.cinema4duser.com/tech_tutorial01.html

good luck

Martin

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