Changing Light Decay?

# 1 23-01-2012 , 10:25 PM

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How can I adjust the decay of a light in Maya? I have a point light (a lantern) and want it to emit light that gets weaker with the distance. I can choose preset Decay Rates in the attribute editor, but they're all too weak.. how can I make a custom decay rate? Thanks

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# 2 23-01-2012 , 11:13 PM

The Nurb Herd
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increase the intensity

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# 3 23-01-2012 , 11:27 PM

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Yeah, just increase intensity. But be aware of the decay setting you choose. I usually don't go past Quadratic. Cubic really taxes my processor.

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# 4 23-01-2012 , 11:32 PM

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That doesn't really give me the effect I'm looking for...

See here:
1)
user added image

This is more or less what i want.. see the light on the porch.. The problem is that there is no decay here.. so the light hits the ground which I don't want to.. I want it to gradually disappear

2)
user added image

Here is Quadratic Decay, light intensity 1... it sucks.. very weak light

3)
user added image

Here is Quad D, light int. 10.. still sucks.. the light it way to strong at its origin and it dies off way to fast, doesn't even illuminate the porch

I read somewhere that you can adjust decay (or light drop off) for spot light using graph editor and then change that light to point light and the decay settings will stay.. but no instructions on how to do it.

Last edited by nov2011; 23-01-2012 at 11:39 PM.

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# 5 24-01-2012 , 12:31 AM

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Well they look alright to me, but you can try a rampLight if you are not happy with the fall off. user added image

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# 6 24-01-2012 , 12:33 AM

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What your trying to do really can't be done with maya lights alone. You need to use Global Illumination. GI will enable your light photons to bounce and spread across your scene the way real light does.

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# 7 24-01-2012 , 02:10 AM

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Ahh yes, getting more natural looking lights in Maya. Assuming you're using MR, you might as well bite the bullet and start looking into linear lighting. Quadratic decay comes closest to real world. The problem with decaying lights is that you risk having the area near the light become overexposed by the time you cranked up the intensity enough to light your scene. This is where tonemapping comes in, so you can clamp the overly bright spots into a range that doesn't make your eyes bleed.

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# 8 24-01-2012 , 04:16 AM

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eh? bite me? Gen!!!

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"A Darkness at Sethanon", a book I aspire to model some of the charcters and scenes

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# 9 24-01-2012 , 05:04 AM

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eh? bite me? Gen!!!

Originally Posted by bullet1968

Yes! Take a big juicy bite! *nom*nom*nom*

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# 10 24-01-2012 , 03:53 PM

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Thanks for the tips guys, looks like i'll need some time with this one.. and I thought there would be a default light to do this, after all it's one of the most common light sources (bulb, candle).

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# 11 24-01-2012 , 10:35 PM

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There's no single light in Maya (or any software) that will create a physically perfect lighting effect. Just like you need several texture maps (color, specular, bump etc.) to create a convincing surface.