DarkElegance, 6000x5000 is a massive image and that kind of size will defintely require a lot of time. I never rendered anything near that size. I would suggest something more reasonable while you get your bearing with Lux. Also, at athat size you have probably consumed all your RAM and hit the swap on disk, which will slow things down to a crawl.

Having said that, the robot image that you posted presents no issue to be rendered with Lux. In fact it can gain a lot. Without seen your scene setup, lights etc I can only guess what happened. Often the issues with grain are caused by misplaced lights. Lights must have a clear path to reach the objects. That is the same that is done in photography. In fact the secret of getting great results at good speed in Lux is to light like a photographer.

Unfortunately a lot of 3D artists have been trained to use the unrealistic model of 3D lights where light path is not as well understood as it is in real life. I would suggest to start over with a simple approach in order to develop the practise necessary:

• Add one figure to the scene

• Add one mesh light, no other lights. If you need to have a light to see the scene make sure that you disable it in Reality

• Set the resolution to standard HD video: either 1280x720 or 1920x1080

• Render

 

Start with that setup and then move the Reality mesh light around to get a feel of it works. Try 5 renders with one light only and see how much understanding you get out of it. When you get the hang od it then add a second mesh light. Or a IBL light.

Hope this helps.

Paolo

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