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Lighting up Megascans lamp with Lumen?

Hello there, I was looking at this beautiful lamp from the Megascans library: https://quixel.com/megascans/home?search=lamp&assetId=vfvjddova

It would be great to light it up in the engine, the material doesn’t seem to offer an emissive parameter and if I put a point light inside the model it obviously casts weird shadows.

Can someone offer some advice on how to make it cast light?

You have to add emissive in the material to the lit part to make it look better. Is it just one material? Then you need to mask out the glass part and add emissive to just that. Looks like you could use a lerp or some other math to get the white part from the material. The rest of the material would just be dark rusty metal. So it’s easy to create a mask.

You can try to put a light into it and give it a large source radius and low strength. Multiply the color of the light to the emissive so both match. I found there isn’t a best practise for how to do this. It depends on your scene. Is it dynamic (moving in the wind) or static? Is there a wall next to it or is it hanging from the ceiling. Just see what looks best. Sometimes placing a light actor next to it works and sometimes it doesn’t. You can use multiple lights if you need to.

Hello S-Dot, thank you for your guidance, you pointed me in the right direction!
I managed to make part of the material emissive by using a mask (red channel + contrast).
You can see the result below.

It kinda works, the problem now is that the light flickers a lot on the wall, like if it was purposedly animated to do so, and when camera is not facing toward the lamp, it turns off…

I guess Lumen is doing something strange?

They mentioned in the Lumen presentation video that small emissive lights should be avoided as light source and you should place a light there instead and reduce the emissive value to a low level. Not sure if it will help. I’ve seen those changing lit areas on walls with normal light actors.

Yes indeed, I’ve been searching around and a few people encountered both problems: emissive light disappearing when not looking the source and flickering direct/indirect illumination.

It looks like there is a technical limitation in the Unreal Engine 5 EA’s Lumen, I guess it will be fixed later on since is really evident.

For now I’ve reduced the emission intensity and I’m messing around with additional lights to overcome the issue, thanks! :wink: