Help getting this "simple" result

I want to create an object that has properties like a laser beam - i.e., the edge fades into nothingness. I once did this in Thea by applying a glass material to a cylinder, setting the index of refraction to 1, and then tweaking some colors (at least this is the way I remember it). Although lame, it came out great for my purposes because there was no hard edge visible. I’ve tried a similar approach with vray by applying a glass material to a cylinder, setting the IOR of the reflection and refraction to 1, turning off thin, and then messing around with the fog parameters. Although fog does something - i.e., the thicker part of the cylinder looks darker than near the edges, the hard edge is still there - i.e., I can’t figure out what to do to make the object surface fade to nothingness. Also, I don’t want to do environmental scattering because I think that’s way overkill for what I’m after. If there were a volumetric object that would scatter, that’d be great, but I don’t think Vray for Rhino supports such an object. For some reason I think this effect should be easy to produce, but all my clicking and Googling hasn’t gotten me too far. Forgot to mention I don’t need an emitter. Mostly I’m just trying to figure out how to do that soft diffuse edge.

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I once did a similar effect. Applying an emissive material to an unclosed cylinder. Then I applied a gradient in the transparency settings. The settings are shown below. Perhaps this will be useful.




Interesting approach - definitely a keeper and easy to set up too. One other thought came to mind after my post where I started to think about shots of the earth where the sphere has a hard edge but the atmosphere provides that nice diffuse edge. Not quite sure how to approach this idea with a simple workflow, though…

The normal way of doing a ‘glow’ or ‘glare’ effect would be just to Photoshop it. I had to do an animation with such effects once and just rendered out in HDR and used a plugin in After Effects.

The same effects are available in the Lens Effects panel during the post-rendering stage.

Besides the Photoshop and emitter approach, any other thoughts on rendering an [transparent] object with a fuzzy edge (no matter which way you turn it) without post-processing? Fur? More playing around with opacity/transparency?

I think it can be two spheres - the smaller one is the Earth, the larger one is the atmosphere. And apply to atmosphere transparency effects with Fallloff or Fresnel maps.

Thanks folks - your ideas are already paying off :grinning: