Hello. I wonder, Why can’t I add strong reflection to translucent materials?
I mean, The materials adds at best a little bit of reflection, but why can’t I decide how much? In archiviz is important to create surfaces that reflects a lot but also allow to see through. I can’t do that, so I have to decide to use a mirror reflection or almost complete transparent surface. In both cases the result looks not very real.
Do you have any screenshots?
This sounds like a materials question, as well as depending on what lighting pipeline you use. In order:
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Are you using the path-tracer, or the real-time renderer. If so, are you using lumen? If so, is the translucency raster or ray-tracing?
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What is your glass material? What is the opacity set to? Your roughness?
Translucency is extremely strange and convoluted in Unreal Engine, and the minutae of your settings can have a massive impact on the final product.
Materials have a specular input which is used to define the specular intensity. It takes a scalar and I believe the default is 0.5 (capped at 1)
Just as an additional piece of advice: For the best quality, don’t use the lit shading model for glass. Its reflections are affected by the opacity and so lowering the opacity to make it more translucent will also make the reflections more translucent.
For high quality glass, what you want is the Thin Translucent shading model. Be warned, it’s expensive to render.
Well, yes, a material question , but also reflection question, because maybe to fix it it’s not just about material, not knowing I chose reflection section… not totally out of the subject 
1 Using Lumen I tried translucency settings with both option but I don’t see any difference about reflection that just doesn’t exist…
I attach you the settings of my glass materials, changing values about specular, roughness etc doesn’t change anything…
Using instead thin translucent model as you suggested these is the result and the settings. That is the max amount of reflection I can achieve, so it’s basically identical to the previous solution. Maybe I’m missing something. Also here I tried to change reflection and translucency settings, I used raytrace, raster, lumen, whatever…
Just like in real life, the reflection visibility depends on the amount of light coming through the glass. In your case, the light coming through the glass is nearly the same as the light being reflected from it so it is really no surprise that it is weak.
Here’s the same scene with the same materials, only thing changed is the rotation of the light:
I tried to add the material to real scenario like you did but this is the result. Again it’s basically transparent even if the interior is completely dark.
I wonder what I did wrong, changing translucency settings in my camera doesn’t change anything
What are the results if you remove the glass? Worse comes to worse, you may need to exclude the mesh from some scene passes in order to get good light propagation. What’s the PT telling you?
If I eliminate the glass the result is identical. Can you share your scene that you showed me as example? There the glass worked properly, so maybe to understand better the problem I can make some tests based on that.
If you eliminated the glass and light isn’t propagating, then that would mean it’s the scene lighting itself affecting your visibility. I’d suggest tweaking your lighting, and what example? I don’t recall one.
Ah sorry, it was another user that sent me the example before. I though you were the same one
Light it is propagating in the house, but like in a real room if you detach the glass from your window it doesn’t enter more light. The interior is dark because it’s dark. I can increase skylight, but It isn’t about that more dark is inside more reflection it should appear? If inside gets lighter it would not have more reflection, but the opposite.
Also I tried the material with a new default scene. Just in case I could have messed up with something, but the result is the same. Glass is not reflecting
Hey there @Arkiras sorry to bother, do you do anything special with that glass material? I believe @Daniel_Mine is unable to replicate that effect if you have any pointers on that!
There’s nothing special about the material, it’s just thin translucent shading model with opacity/roughness set to 0 and transmission to ~0.95. The scene is the default level with basic cubes.
I did use ue5-main for this which is why the reflections are sharp. This will be available in 5.1 as far as I know, but it won’t help if your issue is the brightness of the reflection.
I can only speculate as to what the issue is, maybe it just looks weak because it’s so blurry in which case 5.1 will resolve that.
In 5.0 you can enable screenspace reflections in the material properties, this will get you sharper but low quality reflections for objects that are on screen. That might be sufficient for what you need.
Here’s an example of that (in 5.0)
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Just to update…
Finally with 5.1 I was able to create a decent glass material
It’s a pity that my nanite foliage meshes don’t work anymore, but that is another matter
Ok, I correct myself. Partially solved. sunligh still doesn’t go through, except you use path tracing