Why is my POV-Camera causing reflections?

[Bojock]

The editor-view-camera emits light. You can only see it, when you are close to reflective material.
When I put a camera in the scene, it causes the same light-reflection, and it is also visible when I press play, and look through this camera. You can see in the editor viewport, that this reflection shouldn’t be there, it does not really exist, so it must be a camera-effect.

-It’s not auto-exposure.
-I think it has nothing to do with Lumen, or Screen Space Reflections.
-I can turn specular off in the material of course, then it goes away, but then I also have no specular anymore.
-I do not have any lights or effects in the scene. There is only one skylight, and one directional light.

Here is someone with the same problem from 2015 (unsolved):

What is causing this Light Reflection??

Hey Guys, Still havent solved my issue from before. My ‘character/player/camera’ is causing a bright light reflection on anything shiney in my scene (as if holding a powerful flashlight). Where is this coming from and how can I shut this off? This is not coming from a light source in my scene… as it only appears where ‘I’ go in the scene. Here are a few images of what is happening when I approach a shiney object (in Editor, while playing, and in Cinematic Cameras). Please help! [HighLightFro…

I think there must be an easy option to turn it off, but I searched everywhere and I didn’t find anything.

[Arkiras]

Looks like it’s probably the specular reflection from the sun, as your sun is pointing almost straight down… this is just how light works

[Bojock]

yes, but in the image you can see, that there is no reflection in the scene. You can only see it from the perspective of the camera. It does also not change if I make the sun very bright or very dark, it’s always visible like a flashlight-effect.

[Arkiras]

Make your box a mirror surface, 0 roughness, 1 base color/metallic. Post the result

[Bojock]

Camera-based reflection with mirror-material (under open sky):

Camera-based reflection in a closed room, with only 1 point light in it.

It was a good tip to try this with mirror material, this makes it more obvious, but it still does not give me any clues. Even in a closed room with 1 point-light, the light-reflections are based on the angle of the camera. Even when it looks different, in the closed room it does not look like a flashlight attached to the cam anymore.

[Arkiras]

@Bojock

Even in a closed room with 1 point-light, the light-reflections are based on the angle of the camera

Yes, that’s how specular reflections work. Their intensity and visibility depends on the angle of the reflecting surface, the viewing angle, and the position of the lightsource. Moving the camera moves the appearance of the reflection.

The reason it seems “attached to the camera” in an outdoor scene is because the light is the sun, for practical purposes it is infinitely far away so it has no parallax from the camera position.

If you do not want the specular reflection for a particular light to be visible, you can set the specular scale of the light to 0.

[Bojock]

@Arkiras

Yes, that’s how specular reflections work.

Yes of course reflection-light gets mirrored. But it’s only there when the camera is there. So the light bounces back from the ground against the camera, and from the camera, it bounces a second time back on the ground. This is not how is should work, the camera shouldn’t mirror any light at all.

This is why I made the image, where you can clearly see, that there is no light-reflection on the table-material, but in the cam-window, there is light-reflection. This is the prove that it has nothing to do with reflections, but with the camera-settings. It’s only visible when you look through the camera. When the camera changes the light, only by looking through, then I want all effects removed. I only want the correct reality, exactly like I see it in the editor window.

This is like quantum physics, it only exists when you look at it, but when you look away it’s gone. It’s paranormal activity, this is not how physics work. You could even say it’s a vampire-camera, because you can see the mirror-image when you look thorugh it, but when a third person looks at it, then there is no mirror-image anymore.

To change specular to 0.02, is not the optimal solution, maybe you want mirror-material in same spaces, then you couldn’t use any camera in front of it.

[BananableOffense]

The camera is not mirroring light. The camera is completely invisible and has zero impact on the scene.
The camera angle does impact the visibility of the specular reflection and what you’re seeing is physically accurate, just like Arkiras has said.

You are seeing the specular highlight of the sun (and point light for your indoor scene).

Go look at a puddle outside at noon and observe what happens. You wont see the specular reflection of the sun until you are viewing it from the right angle which causes the rays to bounce into your eyes. (dont look directly at it though, I’m not responsible if you go blind).

Or change the sun/light position in the engine, and watch as the highlight moves.

[Bojock]

I did move the sun as one of the first things.
I understand your logic, that the mirror reflects the sun, or the indoor light, but this is not the problem.

There are 2 cameras, and both cameras show a different reality. There is shining light on the table, the whole table looks white because of the sunlight on it. This is unsuable in any scene where the player has to look at something on the table. But in the other camera the table looks perfect without any reflection on it.

If you look in reality on a table, the light does not change in any way even if you go areund the table and look from different angles on it, but in UE it changes based on the camera. This mst be an effect of the cam-settings, where you get extra-exposure or something like that, something that only happens in the camera, but not in the world, like a filter that you would maybe use later to get a cool effect.

[Arkiras]

@Bojock

There are 2 cameras, and both cameras show a different reality

Because the cameras are in different places viewing from different angles…

@Bojock

This is unsuable in any scene where the player has to look at something on the table

Every other game manages to work with it. Like I said though, you can set the specular scale of the light to 0 and it will not produce a specular highlight

@Bojock

If you look in reality on a table, the light does not change in any way even if you go areund the table and look from different angles on it

Yes it does, because what you are seeing is the specular reflection, which changes when you look at it from different angles.

[Bojock]

@Arkiras

Yes it does, because what you are seeing is the specular reflection, which changes when you look at it from different angles.

This is the same table, only from a different angle in a closed room with 1 pointlight,
and no exposure settings. This is an extreme difference, that is very unrealistic.
If you turn down the specular-power, then the material becomes very unrealistic.
It looks realistic in the first image. When you change the light setting, the second image gets better, and the first is unrealistic then. When you have 2 cameras in one room, then both cameras normally show you the same room, with the same lighting in it.
It seems like there is no other solution. I thought UE has better solutions, but you are constantly saying, that this bad quality has epic-quality and is perfect. I would like to fix it without turning specular down.

[Arkiras]

@Bojock

I thought UE has better solutions

Not just Unreal. Every renderer using physically based shading works this way, because they emulate (or approximate) how light behaves in the real world. You say it is not realistic but give no detail as to why, I don’t know what to say to that.

[Bojock]

@Arkiras

You say it is not realistic but give no detail as to why

Because I don’t want to go into scientific detail. Material is reflecting light, this does not mean, that everything in Unreal Engine looks realistic because this is a fact.

Here is another example, with very dark light. Only by going closer in a dark room, it looks like you have a flashlight on your body. If you think this is realistic ok, but then don’t try to help me. I want to make it look better, even when it means that it will be unrealistic, because for me this flashlight-effect is very very bad. And the solution to turn off specular is clear, I said so in the description, please only help, if you also have knowledge about it. I want the room to be dark, even when it does not make scientific sense. Any solution for my problem would be very appreciated. I am convinced that Unreal Engine has more options and tricks then ‘specular’, otherwise I wouldn’t ask here.

[BananableOffense]

How can you be so confidently incorrect regarding something so easily observable in real life, all while being told by multiple people with years of experience on the subject.

Also, here is what happens when there is more than one sun. If it was the camera causing this, then why does having three suns cause three highlights?

Normal maps, roughness maps/values, and specular maps/values are the main way to adjust this, as are lighting your scene properly. If you shine a bright light at something reflective and then stick your eyeballs right in the path of the reflected light, expect to see a reflection of that light. If you don’t want that, the light must be altered or the material must be altered.

Here is the same wood with some variation in its roughness values, slightly lower specular and a normal map. Most people will find this much more realistic, as the surface is no longer perfectly smooth.

Here is is at max smoothness, showing the reflections of the suns.
I changed the light color to red, green and blue to prove that the directional light is the source.

If this doesn’t prove that the light is the source, not the camera (although like discussed, the camera/eye position impacts how much of that light enters your eyes) then I’m not sure anyone will be able to help you get where you want. Spend more time carefully observing your environment, as this skill is essential to success with these tools.

[Bojock]

I didn’t question that. When you point a flashlight in someones eyes, he will not be able to see anything. The same happens of course if you hit his eyes with the help of a mirror, or any reflective material.

But why do you want the player now to be able to see in the darkness because of this effect? This is way too strong, in the dark it’s like having a free-flashlight, without having any lightsource, and in daylight, you cannot see anything at all. In reality this effect wouldn’t be so strong. I thought, maybe it bounces back several times from the camera to explain why it could be so strong, but I dont’ know why it is so strong. When you come closer to material, it should not lighten up, even when it is a mirror. And if it’s realistic or not, I do not want the player to see anything in darkness, and I want the player to investigate things that lie on the table, without him changing the atmospheric light on the table, in my case it’s impossible to see anyting at all, because everytime you come closer to the table it turns white, this is of course the worst-case scenario of reflections, the only way to deal with it is turning specular down, which I did, but it’s not the best way, it’s only improvisation, I lose the gloss-details with it. If you don’t know any other way of doing this, then your help is not necessary here.

A bubble-volume around the player would be good, that stops all reflections in 2 meter range that would change the environment-brightness more than maybe 5%. But mirrors should still mirror images, the brightness is the problem.

[BananableOffense]

Its not too strong. Unreal engine, and all physically based rendering uses an equitation that follows the laws of conservation of energy. Whatever portion of light is not absorbed by the surface is reflected back. The default value of 0.5 specular represents 4% specular reflectance. In other words, 96% of specular light is absorbed. This is value is relatively close to the true specularity of most materials on earth. All real world materials exhibit at least some specular reflectance.

Roughness measures the sub-pixel bumpiness of a surface and scatters the reflected light in different directions. A low roughness will bound all light uniformly, like a mirror. High roughness will diffuse the light rays.

Diffuse represents the color and amount of absorption of diffuse light. A material with a value of (1,1,1) will reflect all diffuse light and (0,0,0) will absorb all diffuse light. Neither of these values extreme exist on earth.

Its not about closeness to a material, it is about the angle of the view relative to the light, and the size and shape of the specular lobe. You might not think it is realistic, but perhaps that is because a single block of semi-gloss wood sitting in an empty world with a singular light source is not a realistic environment condusive to attractive lighting.

Your claim implies that every artist who uses UE is somehow wrong about how light works, except you and one other guy.

The lighting is accurate. Lower the brightness of the light, or alter the material, learn how light works and stop trying to blame your lack of understanding on the engine.

If you don’t know any other way of doing this, then your help is not necessary here.

If you’re not interested in the correct answer, which has been provided multiple times by multiple people, of which there are no (physically accurate) alternatives, then you will never make any progress.

Change the lighting in your scene, or alter the material.
There is no magic setting that will stop this from happening and if there was, it would break the physically based nature of the material.

For example, you could use the angle between the camera and the surface (dot product) to alter the specular value using a lerp node in the material. But this would not be physically accurate, since real world objects specular value is constant.

Physically based rendering (PBR) means that surfaces approximate the way light behaves in the real world, as opposed to the way we intuitively think it should. Materials that adhere to PBR principles are more accurate and typically more natural looking than a shading workflow that relies fully on artist intuition to set parameters.
-UE Documentation

In other words, your intuition about how light works is wrong. Nothing to be embarrassed about, most game art was following incorrect intuition until fairly recently.

Physically Based Materials in Unreal Engine | Unreal Engine 5.5...

There are some links at the bottom of the doc to the actual science that drives UE and other PBR materials. Maybe read them and come back when you’re done if you still think it’s wrong.

[Bojock]

@BananableOffense

Your claim implies that every artist who uses UE is somehow wrong about how light works

yes ok I got your point:
-UE is perfect, UE is perfect, UE is perfect.

I didn’t say once that I am right and UE is wrong, you can stop fighting me like the UE-police. The problem still exists, that I can see in darkness, which I can not do in the real life, and I do NOT think UE made math wrong, I think UE might have more options about it, that I don’t know of.

[Extrone (Arjun Subhash)]

Unreal Engine 5 Tutorial: Control the Light Reflection (Specular)

[Bojock]

It looks like the effect is only this:
When someone points a flashlight at a mirror, and it hits your eyes, then the light blinds you very bright. In UE the material that would be the mirror becomes then very bright, and it can happen that you can not see the material anymore, because the light is blinding you.

I didn’t think initally that it is this effect, because this effect would normally never be so strong, especially when you look at a table or at a normal wall. The effect also explains why the material can change from very dark to very bright only by changing the camera 1 meter to the side, it can look like a bug, and look very strange. It’s also still a mystery how it works in darkness, because when you go closer to a wall in darkness, then there is always a flashlight-like reflection, no matter where you put your light. This seems unnatural, and it looks like a camera-effect and not like a reflection, but I think it’s the same reflection. I think there are more options about it, and with more knowledge and fine-tuning you could make it very realistic. The only suggestion here was to turn down specular, but I wouldn’t recommend it as the only solution, I think there are much more options you could use to make it look better.