neon glow

[Kyle]

I have created a logo similar to the 'Hard Rock cafe' logo (not my idea). My problem is this - it works fine when it is against a white/silver background but when I put it against a blue background the light glow doesn't work. It looks pretty rubbish really.

Any help or ideas to solve this would be appreciated. Thanks

[Eric Sosa]

it ougth to glow...if you are using the same material and just changed the white/silver for blue.

[Kyle]

First of all. Thank you very much for the reply. I thought the site was down for a moment, with the lack of response:confused:

Anyway, I thought the same too but the glow seems soak into the blue as it were. I have tried vray override material to no effect. Just wondering if anyone had any ideas as to why this is doing this.

[Eric Sosa]

it sounds weird Kyle. how did you make the glow?...vray ligth mat at the back of the logo, glow effect, etc?

 

can't realy understand why is does not show the "glow" when using the same material (properties)...it's only the color you are changing... weird

[Kyle]

Yes that is exactly how I made the glow. I found it a little weird myself so I thought I'd post it up here. And yes just the colour behind I am changing. I might just tell the deigners to change their material to suit me:rolleyes:

[Ray]

Not sure about this, but what if you put an override material on your blue wall with the same reflective properties as the white wall? (Blue as base material, white as GI material.)

[Kyle]

It's puzzling me to Ray.

I tried the override material on the blue wall but to no effect. I'll keep trying, as soon as I get a result though and I'll post the solution up.

[whitetr]

Have you tried cranking up the color on the VLightMtl?

 

Also, do you have GI disabled in the blue background render?

[Kyle]

I have cranked up the colour but to no effect. I am now trying a vray map material over a standard light glow now, seems to work a little bit btter but still not as good as what I want. I will solve this or get them to change the style:rolleyes:

Cheers for the help though, it is much appreciated.

[Electraglide]

I have cranked up the colour but to no effect. I am now trying a vray map material over a standard light glow now, seems to work a little bit btter but still not as good as what I want. I will solve this or get them to change the style:rolleyes:

Cheers for the help though, it is much appreciated.

 

Hang on, if the glow is due to illuminating the blue wall by diffuse reflection, then a white/yellow-ish light color (big R, big G, small B) will reflect pretty much nothing against a blue material (tiny R, tiny G, big B).

 

Bit like having a blue box (0,0,1) illuminated by a red light (1,0,0). You'll get black (0*1,0*0,1*0)

 

Adam

[Kyle]

Hang on, if the glow is due to illuminating the blue wall by diffuse reflection, then a white/yellow-ish light color (big R, big G, small B) will reflect pretty much nothing against a blue material (tiny R, tiny G, big B).

 

Bit like having a blue box (0,0,1) illuminated by a red light (1,0,0). You'll get black (0*1,0*0,1*0)

 

Adam

 

Good point.

What would you suggest then Adam so It would be possible for me to achieve what I want?

[Electraglide]

Well depends really. One could argue that you're getting a result which accurately reflects what a yellow neon against a blue wall would look like - its just how light works.

 

However, you might try hue shifting your neon toward blue and hue shifting your blue wall toward red so they overlap a little more in color space and hence you'll get a larger diffuse interaction.

 

Or, you could have a rough wall surface and use specular reflection. Specular effects are the color of the light source and are not effected by the color of the surface. ie specular reflection of a red light on a surface is always red regardless of the color of the surface.

 

I'm suggesting using a rough wall because specular effects are, by their nature, view dependent so you want to scatter it to reduce that effect.

 

Adam

[Kyle]

Thanks for your detailed reply, it has helped with a little of the confusion.

[Electraglide]

I just tried this in Sketchup and I think you can get some effect by desaturating your light color. I've painted a light source on the back of these characters hovering above a pure blue backdrop:

[ATTACH]27768[/ATTACH]

 

With a light color of (1,1,0) (no lighting at all on a (0,0,1) backdrop)

[ATTACH]27769[/ATTACH]

 

With a light color of (1,1,0.3)

[ATTACH]27770[/ATTACH]

 

With a light color of (1,1,0.8)

[ATTACH]27771[/ATTACH]

[Kyle]

Thanks Adam for all your help. I'll try this after.