How to add a HDRI type background but without the hdri lightning the scene?

Development Rendering
1

Can this be done? I have a ArchViz scene but dont want the hdri to light it. I like the skylight only.

2

I’d be interested to know this as well.

I’ve tried setting the intensity down really low (like to 0.01) and that helps but it’s not perfect.

3

yep… tried that aswell. No good.

4

So you want an HDRI skydome because you like the image but want your own lighting?

How about an unlit material that uses the HDRI on the skydome?

5

The HDRI won’t light the scene until it’s captured by the skylight. You can use the HDRI on the background skybox mesh and use a different HDRI on the skylight directly, use two different meshes with different materials, or a single material with a Reflection Capture Pass Switch to visually see one HDRI but capture another. Few different ways to about it.

6

I think almost all of tutorial will tech you how to add HDRI type background and if you want the HDRI to light your scene or not! normally The HDRI do not light your scene unless you choice Skylight source type to :SLS Specified Cubemap!

7

From the description, it seems, that he uses the HDRI backdrop, which is built to lighten the scene via the HDRI image, and cannot get an unlit material (unless you modify it´s master material). But you still can build your own skydome, like it was done Pre-HDRI-Backdrop :slight_smile: A big sphere (Epic developer content have one with inversed normals, which would be perfect for this job) with an unlit material, which surrounds your whole scene.
And to get your sun/directional light through that sphere, so that it won´t be blocked by it, please take a look at this video, from min 24:20, where he installs a new node to the (HDRI backdrop) materials emissive input to add the sunlight/directional to it.

8

Hi. I’m trying to do the same thing - the above video doesn’t quite cover this exactly. As I’m trying to use a surrounding sphere with a sky texture that doesn’t light the scene in any way. So far I’ve…

  1. Added a large sphere around scene.
  2. Switched off ‘cast shadows’ so my SunSky system shines through it.
  3. Followed this tutorial Unreal Engine HDR Sky Sphere Tutorial - YouTube to create the 2 sided material but added it to base colour instead of emmissive.

This comes close but the sphere self-shadows from the directional light. Causing 1/2 the sphere to slightly darken.

Does anyone have any further ideas on this? I don’t want the HDR sky texture to light the scene in any way - I’m happy with my SunSky system. Perhaps there’s another material setting to prevent the self-shading? So that it ignores any effect from the directional light and only the skylight illuminates it. In 3ds Max for example, it is possible to exclude certain objects from a light source - is this possible in UE?

Hoping to find a solution. Will keep you posted.

Any help greatly appreciated.

Thanks,
Adam