# Directional Light causes harsh white specular line in reflections

**URL:** <https://forums.unrealengine.com/t/directional-light-causes-harsh-white-specular-line-in-reflections/395001>\
**Category:** Rendering\
**Tags:** Water, planar-reflection, unreal-engine, specular, directional-light, Lighting, question\
**Created:** [May 30, 2017, 1:02am UTC](https://forums.unrealengine.com/t/directional-light-causes-harsh-white-specular-line-in-reflections/395001 "2017-05-30T01:02:29Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![anonymous\_user\_af66ec49](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@anonymous\_user\_af66ec49](https://forums.unrealengine.com/u/anonymous_user_af66ec49)\
**Post date:** [May 30, 2017, 1:02am UTC](https://forums.unrealengine.com/t/directional-light-causes-harsh-white-specular-line-in-reflections/395001/1 "2017-05-30T01:02:29Z")

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Hey all!

So got a level where there’s a sun static mesh being paired with a directional light that animates across the sky. There’s a large sea with planar reflections set up, but when the sun/directional light is close to the horizon there’s this ugly white spec highlight that makes the sun look quite odd.

 ![139702-sunlightreflection.jpg](https://d3kjluh73b9h9o.cloudfront.net/original/4X/e/0/8/e086cc68ccc30b903a4b585917abc3a90bf57761.jpeg)

We can’t diffuse the spec hit by increasing the roughness of the water material because that affects its clarity for the planar reflections. As roughness increases, the reflection decreases. And the Lightmass settings are greyed out for directional lights (but not for point lights) which means I can’t adjust the source size from the pinprick that it is in the display. Anyone have any idea how to diffuse or reduce the specular hit from this directional light?

Here’s the current light settings:

 ![139703-sunlightsettings.jpg](https://d3kjluh73b9h9o.cloudfront.net/original/4X/b/b/1/bb12345a326bd1832ecf8ae438813472098ef17c.jpeg)

Thank you so much!

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**Author:** ![redbox](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@redbox](https://forums.unrealengine.com/u/redbox)\
**Post date:** [May 30, 2017, 6:30am UTC](https://forums.unrealengine.com/t/directional-light-causes-harsh-white-specular-line-in-reflections/395001/2 "2017-05-30T06:30:11Z")

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I think its because of water material roughness == 0.

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**Author:** ![anonymous\_user\_af66ec49](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@anonymous\_user\_af66ec49](https://forums.unrealengine.com/u/anonymous_user_af66ec49)\
**Post date:** [May 30, 2017, 5:10pm UTC](https://forums.unrealengine.com/t/directional-light-causes-harsh-white-specular-line-in-reflections/395001/3 "2017-05-30T17:10:31Z")

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This is partially correct. As I said in my post:

> We can’t diffuse the spec hit by  
> increasing the roughness of the water  
> material because that affects its  
> clarity for the planar reflections. As  
> roughness increases, the reflection  
> decreases.

So reducing the water roughness will cause the reflections to become less clear, which is not desirable. Ideally the adjustment would be made to the light, not the material, to prevent it from reflecting so harshly.

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**Author:** ![anonymous\_user\_af66ec49](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@anonymous\_user\_af66ec49](https://forums.unrealengine.com/u/anonymous_user_af66ec49)\
**Post date:** [May 30, 2017, 5:26pm UTC](https://forums.unrealengine.com/t/directional-light-causes-harsh-white-specular-line-in-reflections/395001/4 "2017-05-30T17:26:45Z")

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Looks like it’s a problem with Forward Rendering. I had messed with all those settings multiple times with no luck. Hopefully this can be resolved at some point in the future as it’s a pretty big visual bug for us!

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