Luminous line with gradual disappearance

I would like to make this effect. With emission material. Using color ramp or such, this is supposed to be a straight line, not just glowing ball with blur effect.

Would you mind posting a few details about the setup you’re currently using to achieve the effect as it appears here? I can think of a couple of solutions, but I’m unsure how difficult they would be to adapt to your current configuration. The first solution that comes to mind is as simple as ensuring that your color ramp never goes to zero or full black. But another solution that comes to mind involves using dynamic paint across the surface of a plane scaled to the end result size of the line you hope to achieve as a means to lerp between, a holdout material, a diffuse material, and an emission material, all based on the current location of the object used as the brush. Of course that last solution assumes your effect will be animated. For a static image, I would have probably an entirely different approach.

Try this - first screen is the material settings, second screen is the compositor settings. The material was applied to a simple plane - scaled so that it was long and thin.

But my background is not dark, it’s colorful. If I use your method there would be a black line at the end.

And we were supposed to know that from your post how exactly? We aint mind readers you know.

You can set alpha in the colour ramp. Just make the black part of the ramp transparent.

That what you said is true, but I have an emission shader. So the black or white color stays.

You see, the end of the tail is white (it can be black if I set it so), I want it to be transparent.

Like I said above - change the alpha value of thecolour to be transparent.

or use a second color ramp to mix between your emission shader and a transparent shader.

I did change the alpha value, nothing changes.

Ok - that doesn’t quite work how I suspected.

No problem - just use my second suggestion

Owww, thanks m8, it works, thanks for patience.