Problem with light decay!

[leigh]

Sounds like there is something wrong with the scale of your scene. Is it modeled according to scale?

[Synthesizer]

Yes, like Leigh said, the decay rate is tied to the scene scale. It's normal to have large intensities when you model at a 1:1 scale. I did a quick check and for a light 2m away, with quadratic decay, the intensity has to be around 8000 or so to get medium lighting on it. I've had much higher numbers then that though, its just the way things are in Maya.

[AugieBenDoggie]

My scene appears to be modeled according to scale. Here is a pic.

I checked some of my really old Maya projects, and to my surprise, the decay settings are working fine, and at a more reasonable level. Looks like this problem is with new projects, and I have to set my camera clipping levels ( far and near ) to see the scene grid.

EDIT: For a quadric decay setting, I'm having to set my light at 400000.000 to get a medium light setting. There has got to be something wrong here?

[Ze PilOt]

maybe you've changed the default unit scene.

[floze]

Looks like your scene units are set to millimeter. The decay seems to be always measured in centimeter internally, so an intensity of 400 000 would yield a measured intensity of roughly ~0.5 at distance 900cm (900^2 = 810 000, would be local intensity of 1.0 at distance 900cm, half of it obviously 0.5). Since 900cm are 9000mm, and your light seems to be at ty 9000 units, it's quite obvious that your scene units are millimeter.

An intensity of 400 000 at quadratic decay isnt something you have to be ashamed of. The decay behaves like distance(cm)^2, so it's just natural that the intensity needs to be something between 400 000 and 800 000. Please note that your plane on the image appears to be extending 14 meters (~15 yards or 46 foot), which is quite huge. If it was extending only 1/10th of it and the light was relatively at the same position, it would need only 4000 intensity. I hope that wasnt too confusing..

[AugieBenDoggie]

How do I change the scene units back to cm? I have done a google search but found no help on the issue.

EDIT: Problem fixed, found the attributes to correct the problem. Big Thanks for the help!

[sacslacker]

The online help would surely tell you.

Anyway, try Window > Settings/Preferences > Preferences

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