Physically based material

I am wondering if this is expected.

In the image below I pumped up the metallic to 1 to make the point, the roughness is set to .3. The Cube and the sphere have the same material, but in the sphere the reflection seems much deeper. On the cube a very very very light hint at an horizon the cube and the sphere reflection is only noticeable because of the bright spot.

The issue is that the reflection that I am trying to achieve is much more subtle. So I was quite happy with the result in the sphere below but the cube looks very flat.

from the opposite side, there is a hint on at the cube’s shadow and the sky reflected on the sphere, but nothing on the cube no sphere’s shadow nor sky.

please upload the example 3dm so we do not have to try to guess about how everything is set up

there might be a misconception of what to expect from the geometry. a sphere is like an ultra wide angle lens that will reflect the environment far more drastic and in this case also way more from the dark sky but also from the light source which gives you this deeper impression, while a cube has nothing but planar reflection which will significantly reduce its ability to reflect compared to the sphere.

so just the nature of geometry as far as i can tell.

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That would be my guess…an impossibly-perfectly-flat box is just gonna give you 1 and exactly 1 reflected slice of the environment.

here it is
240619 PBR Reflection.3dm (394.0 KB)

I don’t really think so. The sphere will reflect more of the environment but it should not reflect the environment more.

Long time ago I did this rendering

and to make the cube look like a cube and not a flat rectangle I had to overlay a gradient map like this:

If I understood your question the solution is to NOT make the cube be a cube but add a small “belly” or deformation or bulginess to the flat sides.
Or use the gradient trick.

Hope it helps

i see no other reason for a material to mysteriously decide to behave different. maybe the material does not like cubes it had a bad memory and decides to mock them instead?

try a different renderer but they all will probably hate cubes… cubes are just generally such unorganic structures… actually unbelievable that most of our houses look like that, they are so… how shall i put it…

unreflected. :wink:

if you need more action in the reflection give it more to reflect. a gradient as @skysurfer suggests might work either, i deal with those boring cubes by adding different dark or bright objects into its reflection pathway. unfortunately rhino render does not allow to hide stuff in the camera, but that is where bella for instance shines.

here rendered with cycles,

generally the reflection of a sphere will never look the same to a cube, that is just never going to happen geometrically/physically. if that is still what you would need, photoshop could do, there you can paint objects the way you imagine them to look like.

Thanks for the suggestions, interesting.
In relation to the first material after a lot of tweaking, I added some anisotropy with a small rotation and did somewhat the trick of making the two more similar.

Regarding the second (silverish, more reflective) the cube is actually closer to the material I was trying to get to. it looks ok on the cube but way two reflective on the sphere.

Thanks, N