Interior Room with Artificial Light Only - Noise/Grain Problem

[MGDesignUK]

We're working on a scene at the moment that doesn't have any natural light coming into the scene. It's a room below ground. The scene is lit with Corona IES lights but after many hours the noise (grain) doesn't appear to be going.

All settings are standard with the only change being PT+HD. It's being rendered at 5000px so it's a large image but even after 4 hours the noise is still there!

Is there something that can be done to remove this? Do the settings of the IES files need tweaking? Or do the settings within corona need tweaking? I would really appreciate a quick response if possible.

Many Thanks

[Ondra]

It depends, a picture would certainly help. If your IES profiles are very directional/spotlight-y, you could get some speed improvement by replacing the lights with 3dsmax photometric lights.

[MGDesignUK]

Screenshot of the render currently and one of the settings... Any ideas?

[Siahpoosh]

how many lights u have in this scene ? can u show some screen shot from viewport and light setup ?

[Tanakov]

Have you tryed rendering all in one colour? To see if the noise is present?

Overwrite material 125~, render region of places that are fairly less noisy. Check how many passes do you need to get "ok quality"

If the grain wont go, the problem are lights, if it helped its possible that you have something wrong with materials.

Keymaster, why does Standard lights work better than IES?

[MGDesignUK]

Thanks for the replies guys; there are around 300+ lights in the scene as it's a huge vaulted basement that has been modelled. I will try the same scene with an override material on and see if that helps with things (good idea)!!!

Many Thanks

[MGDesignUK]

The scene renders fine with an override material so I'm guessing it must be a material that is causing the noise. Any ideas on how to check materials etc...

Thanks

[Siahpoosh]

there are too many lights in your scene , i think the main problem is count of lights , but it will be better to post more pic from your scene , then we can help u more .
for now try to turn off reflections and render scene again (with only diffuse maps) , i suggest you to use bump instead of using map for glossiness reflections amount . also check if u have a lot of objects with translucence material. (like curtains)