Reflection Capture Spheres

What exactly do these do? I read the Unreal document and didnt really get what they are used for. DO you guys use these for ArchViz? Or tis it for gaming really.

I read that. What got me confused is why is it needed? Is it because the engine does not capture reflections at default? We have to add it?

With current tech, realtime reflections are not possible for a game engine. At least not good enough to be passable. What most modern game engines do, including UE4, is have probes/reflection capture actors provide the reflection information, and layer screen based reflections on top of that. Yes, they are basically required for arch viz or any scene/game wanting to take advantage of PBR.

Ohh ok. Makes sense. Final question. Do you just put 1 reflection box/sphere in each room or just 1 per whole render.

they can also be useful to BOOST your reflections, if you need it for some odd reason.
for example, I recently set some rendering settings oddly in project settings, and my reflections were all flattened.
sticking a capture sphere (or box or plane) in the scene brought them back up.

Although I ended up just switching the settings back and not needing it, it’s good to know they’re there. I think they’re mostly for performance reasons though.

Ahh ok. That what I noticed. I was confused since I had a chrome lamp and it already had reflections. But when I did put a sphere next to it, it did make the reflection better.

P.S. Also Do you guys make the light stationary or static inside a interior?

Stationary > static. Only use static if you have too many overlapping stationary lights.

Reflection capture actors should be somewhat stacked, have 1 large one for an entire scene, medium sized ones for different areas, and small ones by assets and stuff that need accurate reflections. Also the box reflection capture actors are ideal for rooms, hallways, and can even be used for flat reflective surfaces like glass covered picture frames or small mirrors.

The docs also mention it need bake lighting. What about dynamic lights?