# \[TUTORIALS\] Photons Be Free: Mini-tutorials and other curiosities **URL:** \ **Category:** Community & Industry Discussion\ **Tags:** unreal-engine\ **Created:** [January 18, 2015, 10:11pm UTC](https://forums.unrealengine.com/t/tutorials-photons-be-free-mini-tutorials-and-other-curiosities/19167 "2015-01-18T22:11:33Z")\ **Posts on this page:** 1\ **Showing post:** 24
**Author:** ![Tim\_Hobson](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@Tim\_Hobson](https://forums.unrealengine.com/u/Tim_Hobson)\ **Post date:** [February 11, 2015, 11:24pm UTC](https://forums.unrealengine.com/t/tutorials-photons-be-free-mini-tutorials-and-other-curiosities/19167/24 "2015-02-11T23:24:35Z")
**Wiki Tutorial 1: Lighting Troubleshooting and Tips Guide** > **[A new, community-hosted Unreal Engine Wiki](https://forums.unrealengine.com/t/a-new-community-hosted-unreal-engine-wiki/141494)** > > After over a year in maintenance mode, the official Unreal Engine Wiki is now permanently offline. These resources now live on a new community-run Unreal Engine Community Wiki — https://unrealcommunity.wiki/! You will be able to find content from... This one is still very much a Work-In-Progress as Eric and I work to get some simple troubleshooting and tips up for everyone. We’ve wanted to do this for a long time and have gotten a little bit of a push to make this available for those having issues. The majority of these will be simple steps with a little bit of explanation for the “why” of it all. Over the next couple of weeks Eric and I will be updating this regularly as we knock some of these out. If you see anything missing or something you want covered please let me know and I’ll add it to our list. \*\*Here is what has been added so far: \*\* **General Lighting Tips:** - [Why are my shadows black?](https://wiki.unrealengine.com/LightingTroubleshootingGuide#Why_Are_My_Shadows_Black.3F) - [Converting BSP to Static Mesh Lightmapping](https://wiki.unrealengine.com/LightingTroubleshootingGuide#Invalid_Lightmap_Settings_When_Converting_BSP_to_Static_Mesh) - [Two-Sided Lighting for Single Sided Meshes, or Why does my light come through the roof?](https://wiki.unrealengine.com/LightingTroubleshootingGuide#Two-Sided_Lighting_for_Single_Sided_Meshes.2C_or_Why_does_my_light_come_through_the_roof.3F) - [What if I don’t want to have lightmaps at all or my game doesn’t need them?](https://wiki.unrealengine.com/LightingTroubleshootingGuide#What_if_I_don.E2.80.99t_want_to_have_lightmaps_at_all_or_my_game_doesn.E2.80.99t_need_them.3F) - [Why Does this look nothing like it did before, or Engine Scalability and you](https://wiki.unrealengine.com/LightingTroubleshootingGuide#Why_does_this_look_nothing_like_it_did_before.2C_or_Engine_Scalability_and_you) - [Why is there a red ‘X’ over my light?](https://wiki.unrealengine.com/LightingTroubleshootingGuide#Why_is_there_a_red_.E2.80.9CX.E2.80.9D_over_my_light.3F) **Movable (Dynamic) Lighting Tips** - [Shadow Bleed or Incorrect Shadows](https://wiki.unrealengine.com/LightingTroubleshootingGuide#Shadow_Bleed_or_Incorrect_Shadows) 1. [Directional Light ONLY: Cascaded Shadow Map Settings](https://wiki.unrealengine.com/LightingTroubleshootingGuide#Directional_Light_ONLY:_Cascaded_Shadow_Maps_Settings:) 2. [Adjusting Cascades for better Quality](https://wiki.unrealengine.com/LightingTroubleshootingGuide#Adjusting_Cascades_for_better_Quality:) 3. [All Dynamic Light Types (Light Tab Settings)](https://wiki.unrealengine.com/LightingTroubleshootingGuide#All_Dynamic_Lights_.28Light_Tab_Settings.29:) - [Why does my Movable light shine through my mesh at far distances?](https://wiki.unrealengine.com/LightingTroubleshootingGuide#Why_does_my_Movable.2FStationary_light_shine_through_my_mesh_at_far_distances.3F) \*\*Static Lighting Tips: \*\* - [Lightmap Resolution / Shadow Quality (Static mesh vs BSP)](https://wiki.unrealengine.com/LightingTroubleshootingGuide#Lightmap_Resolution_.2F_Shadow_Quality) - [What does this “Warning: Overlapping UVs” nonsense mean?](https://wiki.unrealengine.com/LightingTroubleshootingGuide#What_is_this_.E2.80.9COverlapping_UV_error.E2.80.9D_non-sense_when_I_build_lighting.3F) - [How do I generate lightmap UVs in the editor?](https://wiki.unrealengine.com/LightingTroubleshootingGuide#How_do_I_generate_lightmap_UVs_in_the_editor.3F) - [How to control Global Illumination with Static Lighting?, or The Wonderful Thing About Bounce](https://wiki.unrealengine.com/LightingTroubleshootingGuide#How_to_control_Global_Illumination_with_Static_Lighting.3F.2C_or_The_Wonderful_Thing_About_Bounce) - [Why is there shadow splotches on my static mesh?, or How to clean those dirty lightmaps?](https://wiki.unrealengine.com/LightingTroubleshootingGuide#Why_is_there_shadow_splotches_on_my_static_mesh.3F.2C_or_How_to_clean_those_dirty_lightmaps.3F) - [What is the “Lighting needs to be rebuilt” in the Top Left corner error?](https://wiki.unrealengine.com/LightingTroubleshootingGuide#What_is_the_.E2.80.9CLighting_needs_to_be_rebuilt.E2.80.9D_in_the_Top_left_corner_error.3F) - [Lighting Quality Comparison, or Production \> Preview](https://wiki.unrealengine.com/LightingTroubleshootingGuide#Lighting_Quality_comparison.2C_or_Production_.3E_Preview) * * * **Planned:** **These are done just not up yet.** **In the works.** --- _[View the full topic](https://forums.unrealengine.com/t/tutorials-photons-be-free-mini-tutorials-and-other-curiosities/19167)._