Emissive trouble

Hello,

sometimes I have problem with emissive materials:

sometimes when I apply it, the object glow and its’ G.I. disappear when I go away from it (just few meters)

sometimes objects don’t glow and don’t emitt any G.I., it appear only lighted, but nothing other.

Solutions for both problems: copy and paste another object that work correctly and modify it …

How do you make a material emissive? Trying to make visible/glowing downlights from ceiling..

Is there a special tutorial showing this? arealights?

Simply doing a long rectangle to simulate a led strip.. When I came near it’s glow and the wall are lighted, when i go away the light seems to turn off…

One of my biggest problems for scene setups too.

Emitters random turning on and off - bug or “feature”?

我不懂英文,但我有一个视频

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