Reflection not showing correctly on renders

Support Lighting and Rendering
1

Hi,
got a bit of riddle, atleast for me. Im doing arch-viz, for lighting I use HDRI with saturation turned down to zero. It leaves me with gray background, which isnt very nice (also most HDRI dont look good anyway, cant match them correctly to get natural feeling and correct perspective). So I made background where I would put hedges or just blue sky, which pass throu light without coloring it (dont know if im describing it well, im not very good with english) and blends a bit with HDRi. In the end it looks like this:

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But as you can see in mirror relfection we can see only HDRi background without my background. Im not sure if I messed up something with nodes or is it render settings:
Here is my glass window setup:
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Here is my background material setup:
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This is how my background looks from the outside if my description is not good enough:
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For mirror material im just using principled BSDF, metallic on full, roughness on zero.

Im not putting my HDRi setup here, cause it’s not containing anything interesting. Texture cordinate → mapping → HDRi → Hue → Background → output

I will be very grateful for any ideas how to fix it :smiley:

2

Hi,

Would you mind to share your .blend file so that I could take a look at it?

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Sure

Got rid of most of unrelated stuff. I translated most basic collections but materials stayed the way i had them

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So you want both your HDRi and the background to be appeared in the mirror at the same time, is that right?

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Yes, I want to see reflection of view from window. Right now reflection is ignoring the background mesh/thingy that I put outsing and showing only HDRi. Ofc solution cant disturb lighting that i have now too much

6

Hi, your problem is that the mirror is reflecting deferent part of the hdri because of the direction it facing.

Projekt1
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I’ve downloaded your scene.
It seems that the roughness of the material is too high and it blurs the reflection.
This is with roughness to 0.

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Thats not it. I know it cause it’s not only in this project, i struggle with it for very long time. If you put mirror 180* to the window then you get this:

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and it’s correct if i wanted to see HDRi only, but behind my window on renders there is blend beteween HDRi and my background mesh/textured thingy.

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Sorry, my arrows might not be perfect, i just meant to show with them diffrence in what we can see behind window and whats on the reflection in mirror. Tiles are ok the way they are now

10

I think, you could try, somehow, mix both of your backgrounds in the “World” settings, or, maybe, merge them into one, via image editors.

I do not pretend on anything. That’s just how I see it.

11

I can’t understand too much…
You want that the reflections , generally speaking, will show the blue background cylindrical mesh and not the HDRI.
Am I correct?

And this without affecting lighting and you want that the direct view from window will show the HDRI and not the background. Correct?

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Sure, that would be easier in theory. But it would affect lighting, make it blueish and thats kinda fine I can correct it with camera settings.

But if I wanted to put picture of buildings behind window it wouldnt work anymore or anything that is colorful.

13

That is an interesting problem anyway. I guess the answer may be somewhere close.

1 Like
14

90% correct. I want mirror showing correct view from behind window, not window showing view from mirror

15

I think you will get closer to your spec’ if you set the window shader mix to 500.

16

Something like this?
image

Yellow reflection
Fuxia diffuse (lighting)
Blue direct view

(I’ve simplified the material applying a Transparent shader to the window glass…putting back the original mix shader, I think that I should add a mix shader with a Transimission Light Path as mix factor)

As I can’t write here for next hours, I’ll put here the modified scene as the image attached.

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It is a bit tricky because reflections will change the lighting, you could do this to your background shader so that the background shows up in the reflections, but it will affect the lighting a bit and give the walls ceiling a slight blue tint.

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Although I think this is mixing the hdri with the hedges in the reflections.

2 Likes
18

Sorry, had a bit hard day yesterday, couldnt check posts here. Yes, I think thats it

19

It’s something :smiley: Not perfect but much better. Thanks!

Yeah, when im thinking about it now, what im trying to achieve isnt pshysically correct. That’s why probably it’s so hard to get as result in blender. Since my background doesnt emit anything, and reflection is rays reflected there is nothing to show in mirror.