Pixie Dust

1. Star
2. Flickering : Some particles glow, some don't

3. When creating particle effects, handle seperately...
Particle's motion
Particle's shading (look)

4.particle emitter:
Legacy particle (emit from object)

render type : switch to cloud (software render) to add radius attribute

5. Particle has its own initial speed
(initial speed is from the emitter)

6. Adjust Conserve value to .95 to slow down particles.

7. Add gravity force field

8. Adjust Dynamic Weight to control the falling speed.

9. Add turbulance field and turn off its attenuation

10. Assign particleCloud shader

11. With no lights but with incandescence
the particles are visible.

12. Turn off color management

13. Turn off auto exposure on ShaderGlow

14. Glow : tight, sharp,
      Halo : fuzzy, soft

15. Add star points and Star level

16. To tighten up the glow, shrink the spread and Eccentricity

17. Use threshold to add glow to bright particles only.

18. Use high quality value like 10

19. Add halo with the similar settings

20. To change the color of the particle while falling down without using any expressions.
Add solidFractal to the incandescence and re-adjust threshold.

21. Using Remap feature, the particles can be tinted in multiple colors.

Download the recorded session

Final assignment

1. Create a 5-second (at least) movie clip of the pixie dust effect. (use mp4 format)

2. Write your name or initial using the pixie dust. (It doesn't matter how many colors)

3. The resolution must be at least 1280x720.

4. The deadline is by 6pm Wednesday (May 6)

5. Send me the movie clip with the following as an email attachment or a link to download.
-Pixie dust movie clip
-viewport screen capture
-Hypershader screen capture  (particleCloud shader)
-shaderGlow settings

6. Do not use the linear workflow since Maya's shader glow is not made for the linear workflow. Just do it in the traditional workflow.

7. Make sure to use your name in the filename as well to identify.

Color Grading part1

Download Wed Session

Download Thu Session

 <Color grading>
1. Color correction            VS.   Color grading
Color correction is to correct colors. (objective)
Color grading is to create a "LOOK". (subjective)

2. example "LOOK"
-Teal and orange color scheme ( typical Hollywood blockbuster )
-Bleach bypass look

3. What to consider?
Vivid          Bleached
Contrasty        Flat
Clean        Grainy
Sharp         Soft/ Diffusive
Dramatic      Casual
Warm         Cool
Low key         High key
Modern          Vintage

4. The first step.
-Level : to check out Histogram
The first thing to tweak is the black level.
And then White level (=exposure control)
And then Set the tone by adjusting Mid-level (mid-tone)

5. Looks : the most versatile All-in-One tool set.
-Subject
Exposure
Spot Exposure
Grad Exposure

-Matte
Color Filter
Diffusion

-Lens
Lens Vignette
Edge Softness
Lens Distortion
Chromatic Aberration

-Camera
Renoiser (film grain)
Neg Bleach Bypass

-Post
Print Bleach Bypass
Curve or S-Curve
Shoulder

6. MOJO
to add instant " teal & orange look / bleach bypass ".

Volume Fog (Light Fog)

Download Wed Session

Download Thu Session


<Volume fog / light fog>

1. Render the Volume fog (light fog) seperately to have more controls in post.

2. Use black Surface shader of Matte shader to all the objects.

3. In Arnold, volume fog will show up in the Emission AOV which is problematic.

4. In Redshift, volume fog will show up in the VolumeLighting AOV and not in the Emission.

5. When dealing with windows ( very bright pixels ),
the bright pixels may have a jagged edge problem.
To cover this up, you can use two Glow nodes. One with a small sized glow and the other with larger sized glow.

6. Volume Ray is Great!!!

Atmospheric Fog

To those who joined the Wed session,
check out the Thursday session since the "simulated Zdepth" issue was covered.
(Watch from 1h16m38s)

Download Wed Session

Download Thu Session  <---Check this one out!

Download (Nuke file, images)

<Atmospheric Effect>
1. Why is the sky blue?
The sun ray scatters in the atmosphere.
The blue scatters first and becomes dominant in the sky.

2.
-Rayleigh scattering:
When the particle is extremely small as air molecule.
Scattering in all directions (omni)
The scattering color is blue (the sky)

-Mie scattering:
When the particle is larger than air molecule.
The scattering direction is more directional(forward).
Depending up on the size of the particle, the color is different. . (The larger the particle, the whiter the scattering )
The fog / the cloud

3. When you render something really large or something really far, you need to take "Distance" into account.
You can just use zdepth information.

4. To add atmospheric effect,
-Add grade to scale the brightness toward black.
(The fog can block the background pixel)
-Add another grade node to add Fog color
-Use the Zdepth image as a mask to manipulate the above grade nodes.

5. Make sure to use unpremult and premult to avoid
edge artifacts and unwanted extra color to the BG.

6. Pick the fog color from the background.
Any color from the background is gonna work.
But the color near the horizon is recommended.

7. Using  regular Zdepth may create some edge artifacts. Since it is not anti-aliased.
I recommend using  Atmospheric fog ( environmental fog ) in Maya.

Motion Blur lecture resources

Here you can download the recordings of the two sessions on Wed/Thu.

Download Wed Session

Download Thu Session

Download (Maya scene, Nuke file)


<Motion blur>
1. Pixel-analysis based motion blur
Pros:
-Easy to use, cheap, fast
-can even work for stop-motion animation
-Just try and see if it works

Cons:
-Works well for linear motion but not adequte for curved motion. (rotation)
-Can generate artifacts
when lack of pixel info. . ( when things are entering the frame or exiting the frame)
with Reflection/Refraction.
when Lighting changes

Best when passes are seperate ( character against black background)



2. Motion-vector based motion blur

What to check?
- How long the motion trail
(duration of the motion blur - half frame is usually good )
- Deformation and Camera must be on.
-To have clean beauty AOV and working motionBlur AOV
go to the renderable camera and turn off Use Global Shutter option and use 0 and 0 for Shutter start/End.
- Red is for horizontal motion. Green is for vertical motion.
Negative value can be used.

- In Redshift, just by adding MotionBlur AOV takes care of setup. But make sure to use Output Raw Vectors option and turn ON Filtering.

-In Nuke, sometimes R and G need to be swapped.
It can flip back again even with Shuffle node (just strange).

Best when passes are seperate ( character against black background)

Redshift render quality control

What's new.
-When converting Arnold arealight to Redshift, the scale mismatch is fixed.
-Redshift render quality control: quick and easy way to set the quality settings.

-Overwrite the old version. 
source HIP_arnold2redshift_SVA.mel and excute HIP_arnold2redshift_UI in Command line then the UI window will appear.

Download