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Increase the distance of a light's illumination

I'm wondering if there's a way to change how far a light will cast it's illumination?

For example, the dominant directional light will illuminate an entire level and gives the impression that there is no limit on the distance the light will travel. Point and Spot lights however seem to have an incredibly small distance even when you max out the radius and the intensity of the light.

If I make a small cave for example, I should be able to place a single point light in the middle and increase it's radius to fill the cave and then up the intensity until the light is bright in most areas however, it seems like this isn't possible in the engine. Near the end of the intensity values, the lights actually generate this weird wave pattern on surfaces and doesn't seem to be able to light an area more than a few dozen feet around it. I'm wondering if there's a way to disable this limit and allow lights to cast their illumination a lot further?

Considering the engine boasts a physically based rendering system, you'd imagine that the lighting would be a bit more realistic. In the real world if I have a 1600 lumen bulb with a radius of 20 feet and place it in the center of a large, completely dark room, it should be able to cast it's illumination to cover 5026 square feet! Yet in Unreal it seems that the brightest illumination setting with the largest radius will only give you a few hundred feet of illumination. It's very confusing to me.

Product Version: UE 4.15
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asked May 12 '17 at 11:03 AM in Rendering

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Try to disable inverse square falloff in light settings

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answered May 12 '17 at 12:25 PM

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avatar image TorQueMoD May 12 '17 at 09:30 PM

Yeah, thanks for the suggestion. I have done that before in the past but it still seems really limited.

avatar image Murnavid Mar 06 '19 at 08:46 AM

but can some tell me why my wall(mesh) has a bright spot when using point light and square inverse falloff? turning it down and tweaking feels better as if gives the lighting i want of a light bright at its origin and then fading.

avatar image TorQueMoD Mar 07 '19 at 12:54 AM

I think the problem is that UE4 was supposed to require less placement of light entities throughout the map due to the new lightmass system (new from UE3) but the reality is that it's still easier to get the results you want by using more light entities. If you take a look at any of the Epic example projects like the Elemental Demo or Particle Effects, you'll see that Epic will place dozens of light entities in a scene to get the correct lighting. There's some sort of disconnect between the documentation and the real world useage.

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i have seen those examples and there are many lights too. i think Post-process settings is causing it!

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in my project i did two lights. on the left is without square inverse while on the right it is with square inverse. this is what i was referring too

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answered Mar 07 '19 at 04:20 AM

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