VrayLightMTL causing noise

Hi

I am trying to make cove lighting, the way I did it was I applied a Light MTL to a renderable spline set the amount to 10, But as you can see in images below that it gives me this unwanted noise I cannot figure out why this is happening?

Please give me some advice; I am new to vray, and have a deadline approaching

Thanks

I am using vray 1.5 with viz2006
My settings are
IR map set to high- LC Subdivs 1000- Fixed image sampler subdivs 4


With the cove lighting object

Without the cove lighting object

You should increase the hemispheric subdivs for the irradiance map, or alternatively, use VRayLight’s instead of the VRayLightMtl.

Best regards,
Vlado

I tried that already, I was at 30 and pushed it to 40, should i try 50, wouldn’t that give me huge render times?

I guess I will rather use vray lights,

Thanks

im supprised how low some people keep it. i never (as i said in another post) go below 60