An almost Physically Based Rendering for conductors and binary alloys. PART ONE

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1

Hi. I have made a set of materials for conductors (almost all metals) using complex refraction index (real and imaginary parts) for red,green and blue channels.
This is a gold node:

metalnode.jpg1280×1024 151 KB


Color and Normal Incident Color outputs are use for binary alloys (examples in the other thread).
I have used conductors fresnel formulas for reflectance but strangely,reflection colors seems to be pale for gold and copper,so, for these metals i have increased gamma correction (maybe not physically correct but i haven’t found other solutions). Usual value is 1.
This is a picture with gold,copper,silver (down) and aluminium,platinum,chromium (up) with roughness=0:
and the same picture with roughness=0.1
metal01.jpg1900×2150 526 KB


Conductor elements in the file :
aluminium
beryllium
calcium
carbon
chromium
cobalt
copper
gold
indium
iridium
iron
lead
magnesium
manganese
marcury
molybdenum
nickel
palladium
platinum
silver
sodium
tin
titanium
tungsten
zinc
zirconium
Other elements can be inserted,changing n and k values (values from http://refractiveindex.info site)

This is a picture with rusted copper and other variations with the Normal Input (in the file there is also a rust node):

metal4.jpg1920×1080 396 KB


I enclose file containing conductors and binary alloys materials in the other separated thread for binary alloys

1 Like
2

nice work thanks for sharing

I did not find the rust node ?

would it be possible to have one node with all the material ?

it was done for another set of PBR mat last month !

thanks
happy bl

3

Hi RickyBlender . The rust node is present in one of the two file conductors1.zip and conductors2.zip,enclosed in part two and three (the other two threads i made).In those files you can find metals and binary alloys.Anyway i send you the copper.blend file separately.
Inside this blend file,there is a version of copper material with the copper rust node (with distinct n,k values) and a rust modifier.
This is a screenshot:

rustnode.jpg1280×1024 191 KB


Feel free to use and modify,no problem.
This is the blend file
P.S. I’ve seen the image of your materials,wonderful !!!

Attachments

copper.blend (3.55 MB)

4

but can this rust node be applied to other mat like steel may be ?

this could give you some ideas
may be talk to him

a little like you did with complex numbers

would be nice to see only one node with different materials !

thanks
happy bl

5

Hi.
Yes you can do it.
The copper rust node is treated like another material,in this case a dielectric material (with dielectric fresnel function inside),with distinct n,k values.
If you want steel rust ,you should insert n,k values which identify steel rust and its color and reflectivity.
The rust modifier gives the normal to plug into the input normal of a material node (any material node) and the map values to mix two different materials.In this case copper material and copper rust material.
This is a screenshot. Steel alloy and copper rust (just an example :-))

rustnode2.jpg1280×1024 209 KB

6

Another example.
I’ve used rust modifier to mix copper and gold,treating gold like a rust

rustnode3.jpg1280×1024 196 KB

or this,using another rust modifier and a third material,copper,gold and aluminium with different parameters:

rustnode4.jpg1280×1024 212 KB