Tag: nuke

CG Compositing Series – 2.3 Material AOVs – Direct, Indirect, SSS

December 31, 2023

Direct, Indirect, SSS (intermediate) passes

In this tutorial, we move down the levels of complexity into the Intermediate category and explore breaking apart diffuse, specular further into Direct Lighting, Indirect Lighting, and SubSurface Scattering

What is Direct Lighting?

  • Direct Lighting is when the Light Source directly illuminates a surface.  This could be considered the “first bounce” or the first time the light ray is hitting a surface.
https://en.wikipedia.org/wiki/Global_illumination

What is Indirect Lighting?

  • Indirect Lighting is all subsequent bounces of the Light.  This can be known as “Bounce Lighting”.  Light is often diffused throughout the scene, and also will pick up some of the surface colors.
https://en.wikipedia.org/wiki/Global_illumination

Direct and Indirect Passes as rendered / calculated separately and combined to equal the beauty render. Direct is only the “first bounce” or whatever is directly in view of a light source. Indirect is all bounces after the first hit (excluding the first bounce).

https://sinmantyx.wordpress.com/2015/03/18/perfect-clamp-1/

Direct and Indirect Lighting in the real world is used to describe a harsh lightsource, directly hitting a room or object and casting harsh shadows, verses indirect or “bounce lighting” which the light is aimed at a wall or ceiling or bounce card, and diffused throughout the scene, creating a more ambient lit environment.

https://www.olamled.com/direct-lighting-vs-indirect-lighting-which-is-better/
https://www.unitopledstrip.com/ru/direct-vs-indirect-lighting/
https://vcut.co.uk/the-advantages-of-contemporary-indirect-lighting-coving-for-residential-and-commercial-environments/

Raytracing – Direct Lighting

https://developer.nvidia.com/discover/ray-tracing
  • Ray tracing is a render calculation used to find Direct Lighting, shadows, and specular highlights.
  • Instead of calculating from the Light Source outwards and every direction in the scene, it saves time by going from the Render Camera backwards, only needing to calculate light rays hitting the camera, and necessary for the creating the final image.
  • It starts from a pixel on the final render and follows the light path until it reflects off or through a surface/material. It then asks “Am I directly illuminated by a light source?” and if so follows the path back to the light source, and determines the distance, intensity, and color of light hitting the surface.
  • If the area is not hit by direct light, it renders as black. This calculation ends after the “first bounce”.
https://www.dualshockers.com/xbox-one-exclusive-quantum-breaks-wip-screenshots-show-advanced-effects-and-comparisons/

Global Illumination “GI” – Indirect Lighting

https://www.scratchapixel.com/lessons/3d-basic-rendering/global-illumination-path-tracing/introduction-global-illumination-path-tracing.html

  • Global Illumination or “GI” involves various techniques to calculate the indirect lighting that occurs when light bounces around in a scene.
  • This process helps to subtly illuminate shadowed areas and contributes to the overall color and intensity of the scene, especially around areas that are hit by direct lighting.
  • There are often many number of bounces allowed, depending on render time and settings. Each bounce inherits color from objects and materials and further distributes light into the scene.
  • The result is a more realistic and natural-looking shot, as it mimics the complex ways light interacts in the real world.

I mention this amazing Raytracing video from Josh’s Channel that breaks down how raytracing is working in the renderer with amazing visuals. The video itself is amazing, and entertaining. I highly recommend watching the whole video if you want to know about state of the art raytracing techniques.

The section I clipped from Josh’s video is between 1:24 and 2:14

Direct + Indirect = Total Lighting

https://www.dualshockers.com/xbox-one-exclusive-quantum-breaks-wip-screenshots-show-advanced-effects-and-comparisons/
https://www.dualshockers.com/xbox-one-exclusive-quantum-breaks-wip-screenshots-show-advanced-effects-and-comparisons/

Image Property of DreamWorks – SIGGRAPH 2010

Image Property of DreamWorks – SIGGRAPH 2010

Real Time Raytracing / Global Illumination – RTX Graphics

Real Time Global Illumination, is becoming the new normal in Real Time Renderers such as Unreal Engine and Unity. More powerful Graphics cards are being upgraded to handle these immense calculations, such as Nvidia’s RTX 3090 or 4090 series graphics cards. These are allowing for real time bounce lighting and reflections, instead of traditionally baked lighting in environments. This all adds significant realism to the scenes and games, and shows just how important this process is to photo realism.

Reallusion – iClone 7 Tutorial – Global Illumination

How can we use Direct & Indirect Passes in Compositing?

1.) Contrast / Color Correction

direct / indirect pass decontrast
  • Individual control of the mids/lows and highlights. Gives more flexibility over the color correction in order to increase or decrease contrast and better match CG to plate.

2.) Filters and FX

  • Adding glow filters to Direct Lighting pass to “punch” the lighting and adding some realistic camera lens fx.  Using direct or indirect lighting passes to drive other FX and filters.

3.) Denoising CG

  • Indirect passes (and Sub Surface Scattering) are very expensive renders, and often arrive with some unwanted render noise and chattering.  Instead of applying denoise techniques to the whole beauty render, applying denoise to only necessary passes can help preserve details and improve final quality of your renders in comp.

CG Denoising Techniques in Nuke

1.) Nuke’s Denoiser

Nuke Denoise Node

We can simply use Nuke’s built in denoiser, it is the easiest to test and doesn’t do a bad job after some settings adjustments. No plugin or external tool required

2.) Neat Video Denoise Plugin

https://www.neatvideo.com/
Neat Video is the best denoiser on the market. It is fairly affordable, and chances are your studio already has a license. It can be a bit heavy, I would recommend pre-rendering the results instead of leaving them live in your comp script.

3.) Motion Vector Denoise

This technique involves using the Motion Vector Utility pass to distort the previous frame and next frame’s pixels, back into the position of the current frame. Usually you see a 3 frame average, or 5 frame average, (current frame, +2 frames ahead, -2 frames before). 

It’s also common to use a TemporalMedian Node to help smooth out noise chattering over pixels that are not changing that much frame to frame.

It’s important to note that we should always try to minimise artifacting and quality loss by isolating degrain techniques to only the problematic render passes, and not every layer or the beauty overall. Typically most of the problematic CG noise is occurring on the Indirect and SubSurface Scattering Passes.

MotionVector Denoise Technique

Some Great tools for Motion Vector Denoising:

Vector Median:

https://www.nukepedia.com/gizmos/filter/vectormedian

Deflicker Velocity:

https://www.nukepedia.com/gizmos/time/deflicker-with-velocity-pass

I do believe more tools could be made using these techniques and shared with the community. If you want to have a go at using this technique to come up with different tools that reduce grainy CG while minimizing artifacting, I am sure the Nuke community would be grateful!

Downloads:

If you haven’t downloaded the FruitBowl Renders already yet, you can do so now:

You can Choose to either download all 3 FruitBowls at once:
FruitBowl_All_Renders_Redshift_Arnold_Octane.zip (1.61 GB)

Or Each FruitBowl Render Individually for faster downloads:

FruitBowl_Redshift_Render.zip (569.1 MB)

FruitBowl_Arnold_Render.zip (562.8 MB)

FruitBowl_Octane_Render.zip (515.4 MB)

The project files and the Renders are separate downloads, so if you have already downloaded 1.1 What and Why files or the Fruitbowl Renders, there are a couple ways to combine them to work.

  1. Either add the .nk script to the previous package (in the folder above SourceImages, with the other .nk scripts)
  2. Or simply drop the Render files into the SourceImages folder of the new 1.2 project folder

Project Files for this Video:

Along with the fruitbowl renders above, here are the nuke script and project files from this video, so you can follow along:

Nuke Project File:
CG_Compositing_Series_MaterialAOVs_Intermediate_DirectAndIndirect.nk

Blender Cube Room Diorama zip ( 3 renders ~ 70MB each, zip file total 204.4MB)

original cube diorama blender files from blender demo file site:
https://www.blender.org/download/demo-files/

Cornell Box noisy Render zip (1.55GB) exr img seq

Special thanks to Valentin Nicolini for providing the cornell box render

Please note the render is using ACES colorspace, so you’ll need to set your nuke OCIO settings to ACES to view this render correctly.

Vray Room – Can be downloaded from this website, look for “download example scene” (36.6MB):

https://www.chaos.com/blog/how-to-use-cryptomatte-render-elements-in-v-ray-for-sketchup

Vray Teapots can be downloaded from this website ~35MB:

https://www.lucamignardi.com/2-5d-relighting-nuke/

The Foundry spheres examples can be downloaded here:

https://learn.foundry.com/nuke/content/reference_guide/toolsets_nodes/toolsets_nodes.html

Since I am using Stamps in the script, all renders can be swapped out at the top of the script where the “SourceImages” Backdrop is, and the rest of the script will get populated correctly

Finally here is a PDF version of my slideshow in case you would like to save for future research or review:

cg_compositing_series_2_3_materialaovs_direct_indirect_combinedDownload

Research links:

https://www.pluralsight.com/blog/film-games/understanding-global-illumination

https://en.wikipedia.org/wiki/Global_illumination

https://www.ledyilighting.com/direct-lighting-vs-indirect-lighting/

https://manual.reallusion.com/iClone_7/ENU/Content/iClone_7/Pro_7.4/27_GI/GI_Basic_Intro_and_Benefits.htm

https://sinmantyx.wordpress.com/2015/03/18/perfect-clamp-1/

https://blogs.nvidia.com/blog/direct-indirect-lighting/

https://lightingdistinctions.com/direct-light-vs-indirect-light-how-to-make-the-most-of-both/

https://3dheven.com/what-is-global-illumination-and-how-does-it-differ-from-other-rendering-techniques/

https://cg.informatik.uni-freiburg.de/course_notes/graphics2_09_pathTracing.pdf

Thank you for all your patience, I’m hoping to publish more tutorials in this series soon.
Best,
-Tony

VFX Nomads Podcast: Episode 001

July 4, 2023


Following the well received VFX Community Nuke webinar hosted by the Foundry a couple months ago, link here, Josh Parks, Tony Lyons, and Adrián Pueyo wanted to do more. So we decided to start recording more of our conversations.

We’re excited to introduce the VFX Nomads Podcast

Along side us is Senior Compositor/Compositing Supervisor and good friend, Gautama Murcho, who shares his wealth of knowledge, offering insights into his experiences in the VFX Industry.

The podcast is also on Spotify if you prefer!

Please Subscribe if you’d like to have new episodes on your radar. Feel free to post comments, feedback, or questions for us to talk about in the future. We hope you enjoy the first episode! 

Why Join the VFX Community? Foundry YouTube Live Panel with Josh Parks and Adrian Pueyo

March 21, 2023

I recently had the pleasure of teaming up with Josh Parks and Adrian Pueyo in a Foundry Live Panel event on YouTube Live. We talk about advice for people starting in the industry, getting into teaching, how to keep learning, and the importance of networking and community.

Josh, Adrian, and I are friends and former colleagues. I couldn’t be more proud and excited to see them evolve in their careers and see their various contributions to the VFX Compositing Community over the years. It was an honor to talk alongside them in what felt like a typical chat we might have if we all met up in person over lunch.


Back in December we decided to create a space on LinkedIn to be a place for folks to share cool nuke and compositing posts. The LinkedIn news feed can be a little bit of a fire hose of information, and if you don’t save something, it can quickly disappear into the ether. If you’d like to be part of the nuke community there, for articles, tutorials, news, and questions, we’d be happy to have you.

Foundry Nuke Compositors LinkedIn Group

I had an absolute blast speaking alongside Adrian and Josh, and in my opinion, it went by too fast! I hope you enjoy the talk and maybe get a little inspiration out of it. I really hope to chat with them again in the future.

If you’re interested in checking out Josh or Adrian’s websites and courses, here are some links:

Josh Parks:
https://www.compositingpro.com/
https://www.nukecompositingtutorials.com/

Check out Josh’s newsletter, Training Courses, and Masterclass series

Adrian Pueyo:
https://adrianpueyo.com/

Adrian just released a brand new Python Course tailored for nuke compositors on his new training platform. Check out his courses page for more info.

CG Compositing Series – 2.2 Material AOVs (Bonus) – Cross Polarization Photography

March 10, 2023
cg_compositing_series_2_2_materialaovs_crosspolarization_pdfDownload

Download the PDF here ^

Cross Polarization Photography

In this Bonus video on Material AOVs, I cover Cross Polarization photography, which is a technique that allows us to separate diffuse and specular components of everyday objects. I go into detail about the lighting concepts that allows this separation to occur, and how it’s used to gather reference and textures to recreate objects in 3D.

Electromagnetic Spectrum

  • Visible Light is a section of the Electromagnetic Spectrum
  • Light / Color is represented in 2D as a Sine Wave with a specific frequency

3D Light Wave Representation

  • The 2D representation looks a bit different in 3D space, since the light waves could be oriented in any and all directions along it’s forward axis
  • A light beam with randomly oriented Light Waves is referred to as an Unpolarized Light

Linear Polarization of Light

Linear Polarization isolates one specific angle of the light wavelength, only allowing a portion of the light waves that were oriented in the that direction, through the filter

Cross Polarization of Light

  • Cross Polarization uses 2 Polarizers that are perpendicular to each other, effectively eliminating the light wave passing through.
  • The first polarizer isolates the light wave to only one orientation
  • The second polarizer, if parallel to the first, continues to allow the polarized light through, but as it becomes more perpendicular, the light gets dimmer, and eventually blocked entirely

Polarization Upon Reflection

  • When unpolarized light hits a reflective surface (with a refractive index different than the surrounding medium, such as glass, snow, or water) the specular reflection is polarized or partially polarized to the angle perpendicular to the plane of incidence. (along the surface)
  • How polarized the Reflection depends on many factors; angle of incidence, material type, etc.

Brewster’s Angle

  • At a specific angle, the specular reflection is completely polarized to the angle perpendicular to the plane of incidence. 
  • This angle is known as Brewster’s Angle.

Unpolarized Diffuse Component

  • Only the Specular Reflection has the effect of the Brewster’s Angle Polarization 
  • The Diffuse Component is Unpolarized, because they are newly emitted photons from excited atoms
  • This phenomenon only happens when the light is reflected off dielectric materials such as water or glass.
  • When reflection occurs on a metallic surface, no Brewster Angle nor refracted light exist

Polarized Specular Reflections

  • Placing a Linear Polarizer filter in front of the observer will Cross Polarize some Specular Reflections if angled correctly.  It blocks the polarized reflection light wave from shining through it
  • This is how Polarized Sunglasses are able to eliminate harsh glares and reflections from dielectric surfaces such as glass, water, snow, etc.

Cross Polarized Photography

  • If you polarize the light source, the Specular Reflection is also polarized (because it’s a mirror reflection of the light wave).
  • The Diffuse Component is unpolarized light because it is newly created lightwaves oriented randomly.  Adding a second polarizer on the Camera, means we can block the Specular Component entirely depending on the angle of the Polarizers.  When the 2 polarizers are parallel, we see Specular + Diffuse , and when they are perpendicular we will see only Diffuse.
  • The Parallel Polarized image gives use the Specular and Partial Diffuse (only Diffuse Component of that orientation)
  • The Cross Polarized image, negates the Specular, and only shows the other half of the Diffuse Component
  • To isolate the Specular Component, take Parallel Polarized image (Specular + Partial Diffuse) and minus the Cross Polarized image (Partial Diffuse).  The Diffuse Components cancel out, and all that is left is the Specular Component
  • This Cross Polarization Photography allows CG Artists to collect photogrammetry data of everyday objects, and allows  them to recreate these objects in 3D with accurate Diffuse and Specular Maps for Physically Based Rendering
  • What seems just like theoretical Diffuse/Specular Render Pass separation in CG is actually a lighting phenomenon that can be separated into Diffuse and Specular Components in the real world

Notice that Metallic Materials have no real Diffuse Color to them, They show up as completely black in the Cross Polarized result.  Metals are entirely surface level Specular Reflections

  • Occasionally, the Diffuse Components of the Parallel Polarized and Cross Polarized Images are slightly different, (brighter or a shift in color for example)
  • In this case, when we minus the Cross Polarized result from the Parallel Polarized result, we are left with leftover color information or artifacts.  The Specular Component can be desaturated to compensate for those color artifacts
  • Remember that in Dielectric Materials the Specular Component is the same color as the light source, but Metals can sometimes tint the Specular color depending on the type of Metal

Light Stage: Cross Polarization

  • The light stage used in films is capturing evenly lit, cross polarized textures of various facial expressions.
  • This helps separate Diffuse and Specular and aids in tracking features of the face

References:

Here are some great websites that go into more detail about polarizations:

Reflection and Polarization of light in machine vision – Toshiba Teli Corporation

FilmicWorlds – How to Split Specular and Diffuse in Real Images

Polarization Explained: The Sony Polarized Sensor

Youtube – Cross Polarization Tutorial: Removing Specular Highlights and Reflections – Classy Dog Studios

Youtube – Cross Polarisation Explained by Grzegorz Baran

Youtube – The Key to Cleaner 3D Scans: Cross-Polarization – William Faucher

PetaPixel – Cross Polarization: What It Is and Why It Matters

optometryzone – How do Polarised glasses work?

Youtube – ScholarSwing – 16 – Class 12 – Physics – Wave Optics – Polarisation

Youtube – Khan Academy Polarization of light, linear and circular | Light waves | Physics

Youtube – xmtutor – What is Polarisation?

Youtube – xmtutor – Third Polariser

The Light Stages and Their Applications to Photoreal Digital Actors – PDF

Light Stages https://vgl.ict.usc.edu/

CG Compositing Series – 2.1 Material AOVs – Diffuse, Specular, Emission

January 27, 2023

Material AOVs

In this post we are going to be focusing in on the Material AOVs Category.

Levels of Complexity

There are different levels of complexity to rebuilding Material AOVs into the beauty, and it all depends on how much flexibility and control you want with the cost of complexity and speed.

Simple

  • Diffuse
  • Specular
  • Emission
  • Other – Refraction / True Reflection

Intermediate

  • Diffuse
    • Direct Diffuse
    • Indirect Diffuse
    • Sub Surface Scattering
  • Specular
    • Direct Specular
    • Indirect Specular
    • Reflection
    • Coat
    • Sheen
  • Emission
  • Other – Refraction / True Reflection

Complex

  • Diffuse
    • Direct Diffuse
    • Indirect Diffuse
    • Sub Surface Scattering
      • Raw Diffuse
      • Albedo / Color / Texture
  • Specular
    • Direct Specular
    • Indirect Specular
    • Reflection
    • Coat
    • Sheen
      • Raw Specular
      • Albedo / Filter / Texture
  • Emission
  • Other – Refraction / True Reflection

Diffuse, Specular, and Emission are the Foundational Categories, and the complexities are subdivisions of the Diffuse and Specular Categories

So let’s first focus on the Simple category of Diffuse, Specular, and Emission and really break those down and understand them fully. This will make the future subdivisions easier, familiarise us with terms and concepts, and help us have a grounded foundation of knowledge for what we are adjusting when using these passes.

The full presentation from the video can be downloaded here in pdf format, for those who want to keep or study it offline:

cg_comp_series_2_1_material_aovs_lightingconcepts_compressedDownload

Adjectives of Specular, Diffuse, and Emission

Specular

  • Reflection
  • Mirror
  • Shiny
  • Glossy
  • Wet
  • Metallic
  • Highlights
  • Pings
  • Crisp
  • Sharp
  • Polished

Diffuse

  • Soft
  • Flat
  • Ambient
  • Natural
  • Rough
  • Earthy
  • Organic
  • Matte
  • Weathered
  • Dull

Emission

  • Bright
  • Radiant
  • Luminescent
  • Glowing
  • Self-Illuminating
  • Incandescent
  • Electric
  • Beaming
  • Shining
  • Luminous
  • Illuminated

Emission

  • Emission is any object, material, or texture that is actively emitting light into the scene
  • This includes any Lights, Super-heated metals, or Elemental FX like fire/ sparks / lightning / magic etc
  • Neon Lights, Screens, Monitors are all examples of real life Emission objects

Diffuse vs Specular

Specular – Surface Level Reflections

Diffuse – Light passes through surface and interacts with the material at a molecular level, Scattering and Absorption allow certain colors to re-exit and scatter into scene

Let’s talk about Specular first andSurface level Reflections

Specular

Law of Reflection

  • The angles of incidence is equal to the angle of reflection

Smooth Surface – Specular Reflections

  • Light Beam = a bundle of parallel light rays
  • Light Beam remains parallel on incidence and parallel on reflection

Planar Mirror and Virtual Image

  • An Image created by planar specular reflection that does not actually exist as a physical object is referred to as a Virtual Image.
  • The Virtual Image appears to be located “behind” the mirror
  • Virtual Image distance =  Object to Mirror + Mirror to Observer.
  • Speculum is the Latin word for “mirror”, which is where “Specular” derives from

The people are witnessing a virtual image of themselves looking back, that is double the distance from them to the mirror. The light travels from them -> to the mirror, and then from the mirror -> back to their eye

Notice the reflected virtual image of the chess piece is in focus, even though the real piece (in the foreground) is out of focus. The camera lens is respecting the mirror’s virtual image distance, even though the mirror itself is out of focus.

Here you can see a ground plane mirror appearing to invert the tree in it’s virtual image

Rough Surface – Diffused Reflection

  • The uneven surface causes the Incidence Rays to hit at different angles
  • The outgoing reflection rays scatter in different directions
View post on imgur.com

Here you see some examples of different CG materials along the Roughness / Glossiness spectrum

Wet Surface Reflections

When a surface is wet, the water fills the gaps and flattens the surface and causes more a specular reflection

Microscopic Surface Details

In these slides and examples we are discussing surfaces at a microscopic level. You might think a piece of paper looks smooth, but under a microscope it has quite a bit of roughness to it, which is what makes it so evenly lit and diffuse.

Metallic vs Dielectric Surfaces

The diffuse and specular terms describe two distinct effects going on.  The Light interacts with materials differently depending on if the material is a metal, or a non-metal (Dielectric)

Dielectric – Absorbs and Scatters light

Metallic – Does not Absorb light. Only Reflects

Dielectric (Non-Metal)

  • Light penetrates the surface level and the molecules of the material absorb and scatter the light within
  • The light photons excite the atoms they hit below the surface. Some of the light is absorbed, and this energy is converted to heat. Then new light rays (photons) are emitted from the excited atoms. Those might excite nearby atoms or exit the surface as new photons. These new photons are same color as our material.
  • The Base Color Texture (Albedo Map) – determines the color of the diffusely scattered photons from excited atoms.  It’s the color that is scattered back out and not absorbed by the material

Metallic

  • Does not Allow light to penetrate the surface and does not Absorb light. They only Reflect light on the surface
  • Metals can be thought of as positively charged ions suspended in a “sea of electrons” or “electron gas”.  Attractions hold electrons near the ions, but not so tightly as to impede the electrons flow.  This explains many of the properties of metals, like conductivity of heat and electricity
  • The incoming photon does not excite the atoms, but bounces directly off the electron gas
  • The Base Color (Albedo) is used to describe the color tint of the specular reflection
“Electron Gas” Model

Notice the Specular Reflections are tinted a certain color depending on the metal type:

On Dielectric Plastic balls, the material color changes, but notice the specular highlights are the same color, maintaining the color of the light or surrounding environment.

Comparison of a Metallic vs Dielectric Material in CG

Chrome Sphere and Diffuse Ball

Used as a reference to see what something 100% Smooth and Metal (Specular) and 100% Rough and Dielectric (Diffuse) looks like in the scene.

Resources:

DAIWTONG824@OUTLOOK.COM

10" 50/50 Chrome and Grey VFX Ball

Diffuse

The diffuse component includes light that penetrates the surface and interacts with the materials molecules. This happens in different ways in the real world

Transmission

  • Light passing through the material / surface
  • Can be thought of as “transparency”

Refraction

  • when light changes angles as it goes through different materials or mediums

Absorption

  • When certain wavelength colors of light get absorbed by the material

Scattering

  • when light is dispersed in many directions when it comes into contact with small particles or structures in the material

Simplified Diffuse Calculation

When the distance that light travels beneath the surface is insignificant and negligible, the calculation can be simplified by the renderer and just calculated at the surface point where the light hits. It uses the Base Color Texture (Albedo) as the Diffuse Color that will scatter. 

Sub Surface Scattering

When the distance the light travels beneath the surface of the material is significant, the interior scattering must be calculated. This is referred to as Sub Surface Scattering (SSS)

Physically Based Rendering Terminology

Albedo

  • Base Color Texture Map
  • On Dielectrics (non-metal) refers to color of material
  • On Metals, refers to the color tint of the specular reflection
  • Texture map is without highlights, shadows, or ambient occlusion

Metalness Map

  • What area is metallic or not. (will use Albedo Color differently). Usually Black or White

Roughness (Glossiness) Map

  • How blurry or how sharp the reflection will be

Real life objects often have a diffuse and a specular component

Diffuse describes the color of the billard balls, but the specular highlights are all the same color (reflecting the color of the light above the table)

Iridescence

  • There is also Iridescent materials that change specular color depending on viewing angle.
  • Iridescence is a kind of structural coloration due to wave interference of light in microstructures or thin films.

Nuke – Simple Material AOV setup

We can break our fruit bowl render into the 3 simple components, Diffuse, Specular, and Emission. They layers look like this:

You can download the nuke script shown in the Tutorial. I created the mini setups for the 3 different types of renderers, Arnold, RedShift, and Octane. Dividing the Beauty render up into their 3 Diffuse, Specular, Emission Components, and Recombining them.

Download nuke script project file

If you haven’t downloaded the FruitBowl Renders already yet, you can do so now:

You can Choose to either download all 3 FruitBowls at once:
FruitBowl_All_Renders_Redshift_Arnold_Octane.zip (1.61 GB)

Or Each FruitBowl Render Individually for faster downloads:

FruitBowl_Redshift_Render.zip (569.1 MB)

FruitBowl_Arnold_Render.zip (562.8 MB)

FruitBowl_Octane_Render.zip (515.4 MB)

The project files and the Renders are separate downloads, so if you have already downloaded 1.1 What and Why files or the Fruitbowl Renders, there are a couple ways to combine them to work.

  1. Either add the .nk script to the previous package (in the folder above SourceImages, with the other .nk scripts)
  2. Or simply drop the Render files into the SourceImages folder of the new 1.2 project folder

This will help the Read nodes auto-reconnect to the sourceImages for you.

Recap

  • Emission / Illumination materials emit light
  • Specular and Diffuse can be separated by Surface Level Reflections and below surface Material Interactions
  • Each individual light ray follows the Law of Reflection.
  • The smoother a surface is, the more mirror-like the specular reflection will be.
  • The roughness of a surface will cause the reflected rays to scatter, and reflection to be blurred.
  • Metallic materials do not allow light to enter the surface.  They only reflect light
  • Dielectric materials allow light to enter the surface.  Light rays are refracted, absorbed, scattered by the materials molecules. Certain color wavelengths re-exit the surface in random directions, which is what we perceive as the materials color
  • Albedo – Base Color Texture. On Dielectrics – color of material | On Metals – color tint of the specular reflection.
  • Sub Surface Scattering is when light below the surface travels a significant distance before re-exiting
  • Iridescent materials tint the color of the specular reflection depending on viewing angle.

References, Resources, Credits

Firstly, Thanks to Pexels for providing such a good resource for stock reference images

I did a hell of a lot of research on this topic before creating the video, I really encourage you to dig a little further and explore the topics more using these great resources:


Naty Hoffman

Youtube – 2015 Siggraph Presentation – Naty Hoffman – Physics and Math of Shading | SIGGRAPH Courses

2015 Siggraph Presentation – Naty Hoffman PDF Paper:

Khan Academy

Video – Specular and diffuse reflection

Video – Specular and diffuse reflection 2

Video – Virtual Mirror

Scientific websites:

Website – The Physics Classroom – Specular vs Diffuse Reflection

Youtube – The Physics Classroom – Specular vs Diffuse Reflection

Website – Olympus LS – Interactive Explanation of Diffuse and Specular

Youtube – Specular vs. Diffuse Reflection, Incident and Reflected Angles | Geometric Optics | Doc Physics

Website – Erika Jame Site – Reflection of Light

Youtube – Specular vs Diffuse Reflection | Physics with Professor Matt Anderson | M27-05

Youtube – Physics with Professor Matt Anderson | Physics with Professor Matt Anderson

Youtube – Reflection of Light Explained Clearly – MooMooMath and Science

CGI Blog Posts

Master of Light – Vector Perez Mindmap

Website – CG Learn – Physically Based Shading

Website – PBR Texture Conversion – Marmoset

Website – Basic Theory of Physically-Based Rendering – Marmoset

Website – JORGEN HDRI Explained

Website – THE PBR GUIDE – PART 1 – Adobe Substance 3D

Website – Material physics in context of PBR texturing – HandlesPixels

Website – PHYSICALLY BASED RENDERING ENCYCLOPEDIA

Website – Tutorial: Blender – Quixel/Substance – Sketchfab: A Proper PBR Workflow

Website – Omniverse MDL Materials

Website – What is an Albedo Map and How to use it ? by Alex Glawion

Website – to buy chrome sphere and diffuse balls – VFX Super Store

Wesbite – Physics Stack Exchange – Why don’t dielectric materials have coloured reflections like conductors?

As always thank you for watching, hope you learned something. More videos to come.

The Foundry Nuke: Gizmo Creation – Tips and Tricks

June 7, 2022

Hi everyone,

The Foundry has recently published a video I created for them earlier this year, Gizmo Creation: Tips and Tricks. Let me know if you found them useful, hopefully there will be more parts in the future. Thanks!

I will just grab the great description from the video the Foundry has provided:

Gizmos are user-created super-tools in Nuke, which are an easy way to package up parts of your node graph into a single group – or Gizmo – so that it can be shared across projects, teams, and Nuke Scripts.

In this video, Tony Lyons gives an insight into how he creates Gizmos in Nuke.

He starts with the User Knob Interface and how it’s been revamped, making Gizmo creation more straightforward and faster than ever before.

Tony then looks at how we can elevate the flexibility and versatility of our Gizmos by adding multiple inputs and a switch node so you can switch between inputs easily.

He also touches on how parameters from nodes within your Gizmos can be added to the Gizmo itself, allowing you to adjust things from the node graph without needing to dive into your tools to find a specific knob tweak.

Want to know more about Gizmos? Check out

https://learn.foundry.com/course/1023…
https://learn.foundry.com/course/6585…

Want to see more of Tony Lyons? Check out https://www.creativelyons.com/

Interested in Nuke? Try it for free here! https://www.foundry.com/products/nuke…

Chapters 0:00
Introduction 0:31
User Knob Editing Toolbar 1:29
Linking Parameters Between Nodes 3:27
Changing Knob Properties 4:28
Speed Up Gizmo Creation 5:13
Customising Input Names 8:01
Changing the Default Input 10:50
Switching Between Multiple Inputs 14:52
Adding Mix and Mask Options 20:13
Adding Channel Options

About Us: We are the creators of industry-standard visual effects, computer graphics and 3D design software for the Digital Design, Media and Entertainment industries. Since 1996, Foundry has strived to bring artists and studios the best tools for their workflows so they can battle industry constraints whilst staying creative. Subscribe to our channel and get the latest news, tutorials, webinars and updates from the Foundry team.

Keying Template Demo with VFX for Filmmakers

February 22, 2021


I was recently on VFXforFilmmakers channel doing a keying demo using my advanced keying template. Matt has kindly filmed some 4K ACES blackmagic footage for all of you to practice on, and we’ve included this nuke script, original footage, pre-renders and final render in the work files for you to play around and dive into.

It’s a great resource and practical case of how I would use the techniques and templates that I developed in the series. By no means the only way to keep, but hopefully you will find many parts interesting and valuable.

The FREE working files can be downloaded from Matt’s website VFXforFilm.com

https://www.vfxforfilm.com/online-store/Spit-Ballin-Episode-1-Keying-in-Nuke-p300452414

New NukeSurvivalToolkit Release v1.1.0

October 4, 2020

Published new v1.1.0 Release of NukeSurvivalToolkit


Added some new tools, fixed some bugs.
For all interested what was updated:

If your interested in the new tool additions highlights, check out this bulletin: https://drive.google.com/file/d/1WziZXM8LSmJxibYckvUV9jbvcLgExUuk/view

Full Release Notes v1.1.0 found here: https://drive.google.com/file/d/1nb_DfkYn44yqc30gD34aEEV3zlh_-shP/view?usp=sharing

Link to new release v1.1.0 download page: https://github.com/CreativeLyons/NukeSurvivalToolkit_publicRelease/releases/latest

If you already have the package installed, should be as easy swapping out the old folder with the new one. In the future I plan to do a monthly release update, given there is enough material to add, bug fix, change, etc.

Please let me know if there are any tools you think I missed and would make a good addition in the comments, as well as any bugs or unusual behavior. Thanks

Nuke Survival Toolkit Release v1.0.0

September 25, 2020

I’m happy to bring you a side project I’ve been working on for awhile,
The Nuke Survival Toolkit!

The Nuke Survival Toolkit is a portable tool menu for the Foundry’s Nuke with a hand-picked selection of nuke gizmos collected from all over the web, organized into 1 easy-to-install toolbar.

Link to the Github Release page:
https://github.com/CreativeLyons/NukeSurvivalToolkit_publicRelease/releases

Link to the Online Google Documentation for full res images and gifs, as well as a nice navigation panel to help search for tools:
https://docs.google.com/document/d/1s9KoiO7MpaLZfKsgIhVnzzpSrdVpTuUhpf-DaOWHWq0/edit?usp=sharing

Many thanks to all the tool contributors out there who made this tool menu possible.

Special thanks and shout-out to Adrian Pueyo for the inspiration and guidance to be able to finish this project. This toolkit contains exclusive AP tools from Adrian and myself that have not been release publicly until now! Make sure to check out all tools with an AP or TL tag at the end.

Any feedback is welcome,
Best,
Tony

DirectionalBlur

July 18, 2019

Directional Blur

Select the rotation angle and size of the blur. Choose between blur and defocus. Has a perpendicular blur that blurs in the perpendicular direction to the angle chosen.

Some helpful options for managing your BBox.

Has channels, mask, mix, etc

View the demo here on youtube:
https://www.youtube.com/watch?v=BrioyN9YMA8&feature=youtu.be

Or on vimeo:
https://vimeo.com/348730566

Download the tool on Nukepedia:
http://www.nukepedia.com/gizmos/filter/directionalblur

Download at my github where you can find a repository of all my tools in one place:
https://github.com/CreativeLyons/Lyons_Tools_Public/blob/master/06_Filter/DirectionalBlur.nk

Enjoy!