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I
am working on another project for BigBoy Productions and I
needed a realistic gold texture with proper reflections but
which doesn’t take eons to render. Years ago I once was very
close to photorealistic gold but unfortunately forgot a big deal
about it. After playing around for days I have finally a good
solution which I will present you in this tutorial.
Software used:
Recommended Skills
The Goal
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Creating a realistic looking gold texture within 3dsmax.
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Gaining basic knowledge about the Material Editor and
Brazil’s rendering settings
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Optimizing the rendering process
1) Start up 3dsmax and set the rendering engine to Brazil if it
isn’t your default engine. If you already know how to do this
you can continue with 2)
1a) Open the render settings clicking this icon on the upper
left or hit F10.
1b) Now scroll down on where one bar reads “Current Renderers”
(“Renderer zuweisen”) and click it, so it expands. Scroll down
until you can see the three assigned renderers for “Production”,
“Material Editor” and “ActiveShade”. If all read “Default
Scanline Renderer” you have to set the Production rendering to
Brazil.
1c) Assuming you properly installed Brazil click on the dots
next to “Production:” and highlight “Brazil r/s V1.2.21” in the
pop-up selection box and hit OK.
1d) Notice that now also the Material Editor’s renderer is set
to Brazil, which is bad becase Brazil doesn’t support it. So we
have to change it back to the “Default Scanline Renderer”.
1e) Hit the yellow button depicting a closed lock just right of
the “Material Editor”. The icon should now show turn grey and
view an open lock - the renderer should change to “Default
Scanline Renderer”. Check the picture below to see if you’ve
done it the right way. Don’t mind the German descriptions

1f) Close the Render Setting by clicking on it’s X-button in the
very upper right.
2) Now open the material editor via hitting M on your keyboard.
If every slot reads “not supported” its rendering is set to
Brazil. In that case continue at 1a).

3a) Click the “Standard” (1) button and select “Brazil Chrome”
(2) and hit “OK” (3). Now we’ve got a pretty neat chrome
material but not at all golden. Note that a reflecting metal
doesn’t have a color itself, it rather filters the reflected
environment in a characteristic way – so forget all of the “Gold
Diffuse Textures” you found on the web. Gold only reflects the
yellow and orange light of the spectrum.
3b) Rename the material from “01 – Default” to “Gold” or
similar.
4) Below, click the white rectangle right of “Filter” and a
color-picker palette should pop-up. Select a warm yellow tone. I
used the following settings: Red 255, Green 207, Blue 23. Click
“Close”.

5) The “Glossy Reflection Control” section. Fist of all, what
does it mean? Glossy reflection control determines how diffuse
the reflection on the material is. It takes a lot longer but
looks more realistic if turned on.

I
rendered the above samples on a 2GHz Intel Pentium M with 1GB of
RAM in highest quality with Global Illumination (GI) turned on.
The little stopwatches indicate the rendering time in minutes.
For the gold-material I chose to keep the initial glossiness
value of 80. If you want it blurrier, decrease it, if you want
it crisper, increase it up to 100. In terms of rendering
performance the glossiness value doesn’t really matter. Only if
it is below 40 it slows everything down a little.
Also important for the rendering time is the sample rate.
Initially it is set to 10 which guarantees a pretty smooth
surface but takes quite long too. I chose a value of 4 this time
but it depends: If the golden object is very close to the
camera, I would boost it up to 10 or even 13. If it was only in
the background, a value of 2 or even 1 would be sufficient.
Below there are four enlarged examples of the cube’s reflection
with different sampling rates of the glossy reflection control.
Note that the value in the stopwatches indicates the time it
took to render the whole image, not only the enlarged cutout.
Glossiness Level was 50 in all four examples.

Please note: The graininess is also dependent on Brazil’s Image
sampling rate and last but not least the Global Illumination
Shade rate. For a detailed walkthrough see addendum A.
6) Still in the Material Editor scroll down to the group called
“Highlight Parameters”. This is where we define what the
highlight of our material looks like.
7) Click on the rectangle left of “Specular Col.” and pick the
same warm yellow tone as above, maybe a little more yellow. I
used the following settings: Red: 255, Blue: 236, Green: 23
8) Below there’s the value “80” next to “Level”. This will
define how bright the highlight will be. I exaggerated it a bit
and set it to 200, so the material will reflect a very bright
light white instead of the orange we’ve defined for the specular
color, just because it is so intense.
9) Now click the long grey button reading “none” right of
“Glossiness”. The “Material/Map Browser” will pop up another
time. Select “Speckles” (“Flecken”) and hit “OK”. Why so? I want
the gold to look like a little like car paint and with the
speckles we simulate the encapsulated metal particles underneath
a perfectly smooth surface.
The following settings kept me busy for days until they looked
right, so you just have to trust me if you want it to look like
my texture or play around with the settings a little yourself.
10) Under the “Speckle Parameters” set the size from 0.1 to 2.
Pretty big specles you might think, but we aren't finished yet.
11) Click the grey map button reading “None” next to “Color #2”.
12) Again the “Material/Map Browser” pops up where we select
“Speckles” – again.
13) Here keep the size of 0.1 but change the color of “Color #2”
by clicking on the white rectangle to open the color picker
dialogue box.
14) Here change the value of “Value” from 256 to 188, or enter
188 for Red, Green and Blue.
Now what did we do that for? We balanced the amount of the
specles so that it still looks natural. I played a long time
with it so I know what I am talking about. To get a better
understanding of what we just did save your work so far and try
playing around with different grey tones for “Color #1” and
“Color #2”.
Important to understand is that in 3dsmax there are hierarchies
in the material editor. In our case the base material is “Brazil
Chrome”. On the first level below there is the fist “Specles”-map
for the glossiness of the “Brazil Chrome”-material. And even
below, on sub-level two there is the “Specles”-map of “Color #2”
of the “Specles”-map for the glossiness of the “Brazil
Chrome”-material. Sounds complicating, but once you are used to
it it’s very practical because there is no limit in sub-levels.
If you want to you can interlink thousands of maps into
thousands of sub-layers.
To get up one hierarchy hit the “Go to parent” (“Gehe zu
übergeordnetem Objekt”) button which can be found far right on
the toolbar below the swatches (the spheres with the textures).
The picture below describes the hierarchy a little.

15) Now hit the “Go to parent” button until it gets grey which
means there is no more level above and see if you're setting
match those below:

15) That’s it! You only have to assign the material to an object
in your scene. You do this by dragging and dropping it from the
swatch in the Material Editor to the object.
16) Adjust the render settings (see addendum A!) and hit F9 to
render.

Maybe your scene looks a little like mine on the picture above
and now you wonder why everything’s so dark and not really
golden. Because, just as mentioned above, gold only looks like
gold when there’s enough to reflect. And in a scene with just
one spotlight there ain’t much. You can either build a huge
scene around it or already have, or you can mock up a softbox-setup
like in a photographer’s studio. I photographed a lot of
reflective objects and it is pretty hard to make it look like
metal.
But especially when you need to render just a golden logo you
don’t have the time to model a complete softbox setup. That’s
why we create a nice reflection just for the gold material in
five minutes or less:
17) In the “Top” viewport create a sphere or geosphere big
enought that your scene including lights and cameras fits easily
in. This will be our environment. Of course, you could do this
in the “Environment” dialog, but then it wouldn’t be so easily
controlable.

18) Now back to the Material Editor. Select a grey sphere from
the swatches and rename it to “Environment”.
19) Click the rectangles next to “Diffuse” and “Specular” and
make them both completely black by entering 0 in for “Value” in
the color picker.
20) Also set the “Specular Level” and the “Glossiness” to 0,
just to make sure.
21) But set the value for “Self Illumination” to 75. You can
increase or decrease this value laer, when you think the
environmental reflection is too weak or too strong.
22) Now click the little grey square just right of “Diffuse” to
open the “Map/Material Browser”. Now select “Gradient Ramp” (“Verlaufsart”)
and hit “OK”.
23) Now you can see a smooth ramp from black to white. You can
add a color my clicking somewhere into the gradient and a green
key appears on the lower side. Double click the green key and
the color picker pops up where you can set the color for the
key’s position.
To delete a key click it and drag it left or right outside the
gradient ramp. It will turn red and the mouse cursor will change
to an upside down arrow with a trashbin.
You can also click into the gradient and drag the mouse. This
way allows you to pick up the value and drag it around inside
the ramp.
It’s pretty easy so you won’t have to play around until you’ve
figured out how it works.
24) When you feel familiar with it, try to make the gradient
look like mine on the picture below:

25) Above, in the “Coordinates” section make sure the “W” angle
is set to 90 degrees, like in my picture. It’s pink for better
conspicuity.

26) Great. Now apply your material to the big sphere in your
scene, again by dragging the swatch on the grid of the sphere.
But we only want to affect our reflection and nothing else.
27) Close the Material Editor by clicking on the X button in its
very upper right.
28) Right click on the sphere in one of the viewports and select
“Properties”. What pops up now may seem rather complicated but
we only care about the tickboxes in the group “Rendering
Control” (“Rendersteuerung”)
29) Untick every tickbox in the group “Rendering Control” except
“Renderable” and “Visible to Reflection/Refraction”.
30) Click OK – You’re done!
31) Click into your “Perspective” viewport and hit F9 to render
your scene – now with proper reflections on your gold material.
Thank you very much!

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Addendum A
We will only focus on the adjustments that matter for the output
quality of the gold material.
1) Hit F10 to open the “Render Scene” dialogue box
2) Click on the tab “Renderer”
3) Now you can see a long list of sections with tags such as
“Brazil: General Options”, “Brazil: Render Pass Control”,
“Brazil: Image Sampling” and so forth.
4) Click on the Tag “Brazil: Image Sampling” to expand that
section. Most important for us aren the “Min Samples” and the
“Max Samples” values.
These values define how many samples per pixel are calculated
during rendering. If it is below 0 then only a fraction will be
rendered which results in a very rough but faster output. The
min value set the minimum of samples per pixels; the max value
defines the maximum of computed samples, e.g. for hard contrasts
or edges.
There are three presets already set in Brazil, and accessible
via the Buttons “P1”, “P2” and “P3”. The worst image quality
offers “P1” with the fastest rendering. The line “Min [-8 x -8]
Max [1 x 1] tells that one rendering sample serves 8 pixels,
utmost 1 pixel.
For a better looking preview hit “P2”. Beware that although it
looks pretty nice the “Min Samples” value is below 1 and
results, especially in animations, in flickering details.
“P3” offers with “Min [2 x 2] Max [4 x 4]” production quality
which we want to achieve, but also takes very long to render.
Why more than one sample per pixel? I hear you asking. The
answer is simple: Quality. The more samples you got for a pixel
the closer you can estimate its color. Edges will be very
pixelated and either one color, or the other. This is also
called “aliasing”. The more samples per pixels you got, the
better the renderer can choose in order to make edges smoother
(=”Anti-aliasing” or “oversampling”). For a detailed description
of anti-aliasing visit
this Wikipedia site.
Of course, you can change the min/max values after selecting a
preset to your needs. Especially when you’re rendering high
quality stills, you might even boos the “P3” settings up to Min
[4 x 4] Max [8 x 8].
5) Click “P3” and close the “Brazil: Image Sampling” section via
clicking on its label again.
6) Scroll to the section labelled “Brazil: Luma Server” and
expand it, yes, by clicking on its label.
In this section everything concerning lighting is controlled,
from direct to indirect lighting, caustics, even global
illumination (GI) and sub-surface scattering. Don’t worry, we
are only interested in a very view settings.
7) Enable the indirect illumination by ticking the box “Enable”
just under “Indirect Illumination”.
Indirect Illumination adds a great deal to a scene’s realism. It
simulates the light not only emitted from direct scene lights
but also the bounced light from other objects.
For example: A spotlight on a red wall in a room would result in
the whole room being lit by the bounced soft red light from the
wall. Without GI you would only see the spotlight on the wall,
the other side of the room would be completely unlit. More on
Global Illumination on
this Wikipedia site.
Of course, indirect illumination slows up the whole rendering,
but you can define just like with the Image Sampling Rate how
you like to sample the GI.
8) In the group “Global Illumination” you can set the min/max
sampling rates for the indirect illumination only. For a fast
preview the values “min -4” and “max 0” are okay, but you can
expect a little splotchy results, which look like a very
compressed JPEG. For a better preview or even production I
suggest staying below 0 saves you time, I suggest “min -2” and
“max 0”. Everything above 0 is pure luxury but looks stunning.
There’s also a tickbox for locking the sampling rate to the
image sampling rate, which is quite practical for previews.
Before rendering your final, you should test a lot the
performance with a very small resolution. Don’t waste a lot of
time rendering details, nobody will see.
http://www.highend3d.com/3dsmax/tutorials/
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