Idea & References
Assets
FX
Rotoscope
MA_VFX 23/24 Beacher22048303
Category: Gonzalo – Nuke
Need to review one’s work before publishing it. No matter the amount of pressure or little time.
Reduce the reliability of the artist.
Stages in Production for Film in Compositing
Temps/Postviz
Trailers
Finals
QC
Software Project Management
Google Docs and Sheets
Ftrack
Shotgun/Shotgrid
Production Roles
Line Producer
Central to VFX project management. Liaise with all aspects of production and post-production.
VFX producer
Ensure the studio completes projects on time and to a high standard.
VFX Dailies
A daily meeting in the morning when artists working on a project meet to share their work in its current state. Ensure that you are moving in the right direction and getting feedback.
Get your current versioned work uploaded.
Tech Check before publishing
Check if you did all the notes for the shot
Compare this version with the old one
Check editorial
any retime in the shot
your shot has the latest CG and FX
Your shot has the latest camera match move
Write in the comments if you have any personal notes
Do you have different alternatives for the shot
QC
Desk Dailies Review (small)
1 VFX sup, 1 VFX Prod, 1 Line Prod, 1 Lead Comp
+ artist (you)
Slack, Zoom, Teams for remote
Small Cinema Dailies (medium)
1 VFX sup, 1 line Prod, 1 VFX Prod, 1 Lead CG, 1 Lead comp
+ tech team + artist/s(your team)
Big Cinema Dailies (big)
VFX sup, line Prod, VFX Prod, Lead CG, Lead Comp – studio team
VFX sup, Director, Producer, Editorial, Lighting lead – client team
Reflections
On-site offers more learning experience than remote/online.
Trust is important.
Word gets out fast so don’t be “that” guy/girl.
Categories
28/11 3D Matchmoving
3D Tracking in Nuke
There is an additional axis involved for 3D tracking in Nuke.
You can extract cameras, and position information in Nuke.
From Nuke version 15, there is support for USD file format.
Axis in Nuke is a null/locator.
Tab in the viewport to switch from 2d to 3d view.
Basic UI/UX navigation is similar to most DCCs.
Pixel Analyzer.
Workspaces can be customised as well.
grains more in darker areas, lesser in the brighter areas
.dpx is an older image file format
renders from CG should be clean and free of noise, grain workflow will be done in post-production
Scanline Render/Camera/Sphere
multisample tab to adjust the sample size, to adjust the quality of the render
3D Geo, Lights and Materials
All 3d objects exist here in the 3d scene node
Lens Distortion
All camera footage is shot through a lens. A lens is a series of curved pieces of glass that bend light and “focus” the rays on the image plane.
Lenses with different focal lengths produce different lens distortion and even with the same focal length, no two lenses are the same.
Workflow for compositing, undistort-> doing comp work -> bring back lens distortion afterwards
DP on the production site will take down lens information, and take a picture of the distortion grid to record the distortion.
Other information recorded on set will include, chrome and matte balls, Macbeth chart, and 360-degree image for HDRI.
For plates without any grid, we need to manually draw those lines. Both vertical and horizontal guidelines need to be drawn. One line needs to have at least 4 points to be considered a guide.
STmap
Works with Nuke. Also lighter with STmap.
STmaps move pixels with a texture map (U,V) with green and red channels.
Also, know as a forward channel for undistortion and backward channel for distortion.
Assignment: Balloon Festival
This is my final product for my Nuke term assignment. I will do an individual post to cover the process.
Reflection
Today is the last day of the workshop style class as Gonzalo is not going to cover any more compositing until the next term, we were given a sneak peek into what we are going to cover for next term which is 3D match moving. Also, we reviewed our Balloon Festival assignment. We covered the 3D aspect of Nuke and learned about len distortion and how we work with footage with distortion.
Categories
21/11 2D Cleanup
The Rotopaint node has more added features compared to the roto node.
A little similar to Photoshop.
Operations:
Brush – unlike Photoshop, there is no custom brush. We can paint with blend modes as well.
Clone – Hold ctrl to sample and paint, and shift to adjust the brush size.
Use lower opacity for a more refined result. adjust brush edge hardness when needed.
Blur – similar to Photoshop blur
Dodge and burn – for painting in shadows with burn and highlights with dodge.
Can set either single frame operation or entire frame range.
All edits are recorded in the node and can be further edited. parameters that can be edited such as transformation, stroke, lifetime, and shape.
Rotopaint can also generate custom-painted alpha channels, just need to enable in the hidden folder
Difference node helps to isolate the difference between two images.
For clean up, we need to denoise the plate because the cleanup will stand out on the plate with grain. Normal workflow would be to denoise the plate first, do the clean up then re-introduce the grain.
Match grain by channel.
Grains are super important as they occur in almost every shot
F_regrain samples an area (the flatter the area the more stable) then applies a similar grain pattern) only NukeX.
Kodak Grain, sets grains by RGB channels, normally the biggest grain is in the blue channel.
Need to match-move before applying the cleanup.
Homework assignment: do before and after, do more damage.
Tips for hand-painted motion blur and smear
Grains/Noise
Grain can be extracted by using the minus operation for the original plate with the denoised plate.
Changing from linear to cineon color spaces will reveal more grains in the darker areas, purely for visualisation purposes.
Cons: will work on flat sections of the plate. but will not work for uneven surfaces because of the way the grain is distributed and arranged.
Newer workflow is done using the DasGrain gizmo by Fabian Holtz
Localised grain application, with common_key and DasGrain node.
Normalise grains, as grains are not even spread throughout the plate.
Grains more in darker areas, lesser in the brighter areas
Gizmos can be copied and pasted and shared, they are just Python codes.
Reflection
Today we learnt about roto paint tool to do some clean up to the plate. For assignment we are suppose to do a messy class corridor scene. I feel like the given examples gives me a haunted vibe. So why not just add a floating “spirit”(its actually Dark Sun Gwyndolin from Dark Souls)?
I create the scene in 3D then place various 3d models i found online. The main character also has a smoke simulation to it on top of the floating animation. I also tried to match the lighting as much as possible. Then I rendered out the scene.
Finally, I composited everything in Nuke and graded it. Of course not forgetting the main point of the class is to do some clean up. I covered up some of the pasted posters and added some graffiti on the walls as well.
Recap: Ctrl mouse click to the viewer will sample pixel details on the frame, Ctrl+shift will sample the average pixel detail on the screen
Filtering
Reformat:
When scaling up an image, do not scale it more than 10%. If not the image will start to lose details and become softer.
https://www.topazlabs.com/ good upscaling software
Concatenation
Concatenation is the ability to perform one single mathematical calculation across several tools in the Transform family. This single calculation (or filter) allows us to retain as much detail as possible.
Do not break the concatenation, it blurs the image. It happens when adding nodes with filtering (transforming).
Filtering (and Motion blur) is recognised only at the end of the node tree.
BBOX ??
Shuffle node
A powerful node that allows the manipulation of different colour channels (as well as other AOVs) to the output result.
AOVs can also be accessed in the shuffle node
TIP: For animation ease, select keyframe and press H.
Planar Tracking exercise
Defocuse with depth pass, Use defocuse instead of blur.
Zdefocus gives more control as it utilises the depth pass. There is an option to control the focal point apart from the size of the blur.
Native to nuke, we can render out 3D objects with depth pass as well to apply defocus.
Bokeh, added to nuke on plugin from v14 onwards. It reads real camera values. The node is really good based on the inputs. But very slow. only in NukeX only.
Assignment: iPhone Planar Tracking
Reflection
Today we did a bit if planar tracking exercise, we are suppose to track and mask out the fingers on the phone. The brief was to stablise the shot and create an interesting animation of the screen reacting to the movement of the fingers. Using tracking and stablising, I was able to create a mask area to replace the screen with a interactive iphone screen. I used a bit of houdini to simulate a cloth drag for the first swipe and particle simulation to show the second swipe.
Categories
07/11 2D Tracking
Transform model
2D track – flat
2.5 track – parallax
3D track – pure 3D
2D tracking workflow:
add tracker node
make a new tracker, and place it at one corner of the TV
the first box searches within, and the second box is the search limit
Play track, and export match move one point. this creates a new transform node that links to the tracker node and has the tracker data.
The order of the track location matters.
stabilising shots
Reflections
I have seen similar tracking methods in After Effects and it was quite popular a few years ago. It is a good start to build a foundation for 3d tracking. I had a lot of fun picking out the posters and placing them in the footage.
Assignment: Planar Tracking Street Poster
Categories
31/10 Merging + Color
Concept of Premultiplication
Softwares like AE already premult layers
Page Up & Page Down to scrub AOVs
Instead of a layer system, the node tree system is a list of instructions
Merge Node and its operations:
- over
- mask
- average
- overlay
- stencil
- minimum
- maximum
- under
- etc…
Reformat node: changing image size/format. Upscaling will result in the degradation of image quality. You can choose the interpolation methods but the result is often jittery. Can look at AI tools if upscaling is really needed.
Premult Workflow: Unpremult to divide by alpha -> do grading and CC -> then premult
When doing grading, we process and treat RGB separately from Alpha channels.
Colorspace and linearisation
32 Bit Color
Colour Matching Methods:
1. Edit the white point of the original colour, then adjust the gain.
2. Divide color, then multiply
Ctrl Shift-drag to get an average colour data
Alt + K for cloning nodes creates a reference copy of the node with linkages for all the parameters.
QC
Control highlights, mid-tones and low
Reflections
Today the main takeaway for me is the concept of per-multipilcation. To do image edits, we need to unpremult before doing any operation to the image. This is because there is extra image data in the channels that we are not aware. This information is new to me and I will definitely keep this in mind the next time when I do compositing.
Categories
23/10 Rotoscoping
General Roto information
Rotoscoping for VFX is used to create a matte or mask for an element from a plate, so it can be extracted out to place on a different background or edited. Rotoscoping gives artists a chance to produce scenes that would otherwise be difficult to do in real life. It also allows us to edit out unwanted elements in post-production. the possibilities are endless.
Roto Node and Rotopaint are generally similar. Rotopaint allows you to paint on the plate. But the roto node is lighter.
Colour Channels & Alpha
Mattes can be located on each channel
Motion blur in mattes is important, and often roto mattes have motion blur included
Rotoscoping
Divide and conquer, split the subject into parts for the roto mask.
Lesser spline points will result in a smoother animated mask
Roto Assignment: Running Man
The assignment brief was to create a matte for the running man as well as the bridge railings from the plate. The following is my attempt at the assignment.
Reflections
Today we learnt about isolating specific elements within a plate into different layers. It involves creating an animated mask which is black and white so that we can use different pixel operations to extract them out from the background. I find that this is a incredibly tedious task. Although Gonzalo said it can be quite nice and easy to do, I find that my mind when numb when trying to shift those individual keys to create the roto masks. Perhaps my workflow is not that refined, but I did not enjoy the entire process. I also was not pleased with my final result of the running man as I see a lot of problems with my work. I will need more practice to get better.
What does a digital compositor do?
Compositors create the final image of a frame, shot or sequence. They take different digital elements; like the animations, background plates, graphics and special effects (SFX) and put them together to make a believable picture.
General Pipeline of a film/movie
Three routes in an established production company
- Technical Artist
- CG Generalist
- Compositor
Digital Compositor progression:
- Roto
- Prep
- Junior comp
- Mid comp
- Senior comp
- Lead comp/department head
- 2D sup
- VFX sup
Software for Compositing
After Effects
- Layer based compositing
- 8/16-bit colour, for broadcasting use
- Most of the time, not computationally heavy
- popular with motion graphics
- Unstable performances with large data files, and other colour spaces other than sRGB
- Missing features for digital compositing
Davinci Resolve
- Node-based
- better colour management
- works well with heavy files
- Free
- Comp and grading in the same software
Nuke
- Supports USD (universal scene description)
- Customizable
- Comes in different types
- NukeX
- Nuke Student
- Nuke Non-Commerical
- Nuke Indie
Nuke
More information is available in the documents in the week 3 folder.
What was went through:
- UI navigation
- Toolbar
- Node graph
- Properties
- Viewer
- Some basic shortcuts
- Nuke script format, open projects, save projects
- Workspaces
- Node groups
- Commonly used nodes
Feedback
Comments: Pay more attention to telling the story. Need more direction.
Next week’s homework:
Practice and get comfortable with the software
Next class: Rotoscoping
Reflections
Today’s class is still covering a bit of theory. Gonzalo covered in detail what the job of a compositor entails and where compositing is positioned in the pipeline. He also covered the general progression of a digital compositor. We then moved on to talk about the differences between the different general compositing software in the different industries.
The later part of the class, we finally proceed to open nuke. Gonzalo very patiently introduced us to node based compositing with Nuke. He also covered some common nodes that we will be using often in our journey. He assured us that it is alright to not understand everything that he covered as it might be overwhelming at first, but eventually we will get it. I really like the pacing of his class as it was not too fast nor it was slow. I look forward to more Nuke classes as it seems interesting.
Mise en scène
Goal is to communicate an idea through “Mise en scène“.
Visual storytelling = an emotional experience for the viewer.
“Mise en scène” is the combination of everything that appears in a frame.
Every shot is designed to stay true and adhere to the film’s theme.
Movie example: Up in the air. Framing composition breakdown.
Movie example: The Wrestler. The rim’s shining light separates the character from the background. Focus mainly on the character silhouette rather than the expressions on the face.
Composition
The placement, size and visibility of an element in the frame will affect how an audience understands its importance to the story. Also known as Hitchcock’s story.
Movie example: 2001: A Space Odyssey. The contrast of colour added perspective. The character goes deep and forward. Very directional. Direct the audience’s glaze to the centre. Very clean shot, not messy and full of stuff.
Aspect Ratio
Every comp starts with the dimensions of the frame.
The most common for cinema is 2.39:1 (cine scope). 2.35:1 is popular in modern days.
For web content, 16:9 is widely used.
Frame Axes
Every frame has two axis X & Y. However, there is a third when composing a shot, which is Z-axis, also know as depth. This is an important element to prevent a shot being too flat looking.
Movie example: Children of Men (2006), using fog as a tool to show the environment of the set.
Movie example: Apocalypse Now (1979) camera closeup to show intimacy.
Rule of the Thirds
Movie example: Se7en (1995). Conventions to create a harmonious composition. third guideline helps to place the essential elements in the shot. 4 points in the frame.
Movie example: Prometheus (2012)
Movie example: The King’s Speech.
Movie example: TRON: Legacy (2010), the rule of thirds is not adhered to, the character is at the centre for symmetry. which is also a composition/framing technique.
High/Low Angle
The height of the camera can change the audience’s perception of that subject.
High angle, makes the subject look powerless
Low angle,
Changes the power dynamic between subjects.
Movie example: No Country for Old Men (2007)
Movie example: The Silence of the Lambs (1991)
Shot selection
For filmmakers to categorize and name different shots. Define the size of the elements in the shot.
- Extreme close up
- close up
- Loose close up
- Tight medium shot
- Medium-full shot
- Full shot
What is Light?
Arts definition = trans-cultural language that evokes a common emotional response in the audience.
Good lighting makes the illusion of cinema feel real.
Light radiates outwards and spreads in every direction from the source.
Take note that light can spill over
Light can also be refracted & reflected
Light can be absorbed, and the rest of the wavelengths are reflected back as the colour we normally see.
Brightness vs Exposure vs Gamma
Brightness: make everything brighter or darker evenly.
Exposure: more effect on brighter parts, less effect on darker parts.
Gamma: more effect on darker parts, less effect on brighter parts.
The Four Main Attributes of Light
- Intensity of light
- Measured in F-stops
- Sometimes known as exposure
- Quality of light
- Soft light
- Soft-edge shadows
- Wrap around the subject and bleed into the shadows
- Hard light
- Defined edges, little fall-off
- E.g. sunlight
- Size of the source
- Source distance from the subject
- Filtering
- Soft light
- Angle of light
- Position of the light in relation to the subject
- Core lighting setup (as a baseline) is three three-point lighting
- Key light, 45-degree angle towards the subject, main source
- Fill light, 45-degree angle opposite the key light
- Rim/backlight, behind the subject, illuminates the subject dimension/volume, separation from the background.
- Movie example: Amelie (2001)
- Movie example: Blade Runner (1982)
- Movie example: Schindler’s List (1993)
- Colour of light
- RGB = White light
Colour Temperature
Light has its native temperature. It is measured in Kelvin as a standard unit.
Colour grading
The process of manipulating the images to achieve a stylistic look. Mainly the colour and the contrast of the film. Some examples include complementary colours, Analogous colours, Triadic colours, and monochromatic colours.
Movie example: Drive (2011)
Movie example: Hugo (2011)
Feedback
Review of last week’s mood board related to time:
- Sentences need to be concise and efficient. Get to the point.
- All images need to tell one story instead of individual stories.
- The picture with the white background stands out from the rest of the mood board. It would be good to have coherence between all the pictures.
Reflections
Today we continued with the second part of the cinematography lesson with Gonzalo. For this class, I think the most inspiring part of the class was about the composition of a shot. Especially the rule of the thirds and the shot angles. I feel that as aspiring film makers (sort of) it is important to understand the reason why a shot is framed. Following the general guides for the the rule of thirds will definitely help us keep our shots grounded and be more aesthetically pleasing. Next lesson we will start with using the nuke software. I look forward to it.
Homework for next week is to record about 10-15s about travel.