Energy slump

 The data said "great night's sleep", the body said "ugggggghhhhhh". I struggled to get out of bed. Me, whom my wife has regularly accused of being a "morning person". This may be the tail-end of this infection, or perhaps this time of year is my peak SAD (Seasonally Affected Disorder) time? Anyway you spin it, I'm barely functional.

True Terrain Sketchbook

I should have completed a couple of Blender School lessons, but I'm not sure I'd get any benefit from them. Tomorrow I'll be closer to being back on track.

Not recovered, but somewhere along the road

I still feel pretty bad

It's a Monday morning. I spent the weekend urgently trying to get better. Lots of attempts at extra sleep, a bit of exercise, but nothing excessive. Usually, two rest days go a long way towards recovery from a regular infection. The good news is that after a good night's sleep, I woke up yesterday feeling like the worst was over. The bad news is that these things can have a long tail. I might feel ill for a long while, even though I no longer feel terrible. I'll look on the bright side -- I'm not hospitalised from a runaway COVID infection, and I didn't fall ill in the days leading up to our trip to the Netherlands. So there you go. My worst bout of sickness in years.

So it's True Terrain time! Feels like reruns...

Under the weather

I have flu-like symptoms, just under a week since I got the flu jab. It could be COVID. It's not kept me off work, but I have zero energy or effectiveness.

Naturally, I have been treading water, creatively. Rendering World Creator terrains using True Terrain 5.

It passes the time, but doesn't move me forward. If I'm feeling better over the weekend, I'll embark on more Blender-School.

Battlefield 6 releases today. I've always been a big fan of the franchise. I liked the last one, but I didn't love it and stopped playing because, at the time, it was crashing my system due to a CPU stability problem. I am probably going to get it, and it will cost me some productivity. 

Blender-School: Photographer 5: Overview

 This is an overview of the Super Blender Addon Photographer, which enables Blender to use industry-standard measures for rendering and lighting, allowing you to operate in a production environment where real-world measures, such as exposure levels and colour temperature, are used.

Photographer addon is not available from SuperHiveStore. You need to go to Gumroad.

Installation

Standard steps. Drag-and-drop into Blender to install or update. Easy!

Menu

Once installed, an extensive menu appears on the N-panel. The following panels are available:

Camera Fost FX

A list of post-process effects that you can enable and configure through Blender's primary workspace. No need to switch to the compositor. I'll not go into the different effects here as they're one of the addon's side hustles.

Camera List

When setting up complex multi-camera shots, this panel provides much easier control, as each camera can use its own parameters. You can switch the view by selecting the camera icon.

Main Camera [M] is an important concept. When you have a main camera, additional cameras that you spawn will inherit some of the main camera's critical parameters to ensure they work seamlessly.

Inherited properties are:
• Camera Overrides (World, Frames, Sampling...)
• Camera Post FX
• Exposure
• White Balance
• Resolution

You can set each camera's Target and show its focus plane.

You can create a Done Camera, which can move between a scene's cameras, adjusting to each camera's parameters as it moves. Use the up-down buttons to toggle your view through all the render-capable cameras.

Camera

The camera panel enables you to configure the sensors of real-world cameras, with a few popular professional cameras available as presets. With the lens focal length, the sensor size defines the field of view of the image. The larger the sensor, the wider the field of view. More

Lens

Select the camera's lens. There are presets of popular real-world lenses. You can tweak the lens position using the Lens Shift V (Vertical) and H (Horizontal) controls, or Dolly (zoom) the lens in. These are useful because they don't require that you move the camera. More

Exposure

The Exposure controls offer three different approaches. 

EV
(Exposure Value) is a simple mode that allows you to set your scene exposure according to physically based lighting guidelines, without affecting motion blur, depth of field, or film grain.

Auto 
Exposure mode that calculates the Exposure Value by sampling the viewport to calculate the average brightness of your scene. With Exposure Compensation set to 0, this average value corresponds to 18% luminance, similar to light meters and cameras, much like a camera's auto-exposure functionality.
See Auto-Exposure Tutorial.

Manual Exposure
This mode exposes controls you will find in real cameras: Shutter Speed (or Shutter Angle), Aperture and ISO (Sensitivity).

Depth of Field

Enabled, this feature supports the rendering of depth of field, where elements that are outside of the focal range will be blurred and distorted, which can provide a pleasing quality.

Focus

Use the Focus panel to set where the selected camera will focus. There are three quick modes that you can use:

AF-S (Autofocus-Single) Select a mesh in the scene on which to place the focus.

AF-C (Autofocus-Continuous) Instead of selecting a target, the camera maintains focus on the centre of its frame.

AF-Tracker: Starts a picker that allows you to pick the surface of an object to create an empty in that location, parented to the object you selected. This empty will then be used as a Camera Focus Object. This can be used to easily pick the eyes of a character, and then ensure that they stay in focus during an animation. View a focal plane tutorial. Focus planes don't render; they only appear in the viewport.

White Balance

White Balance allows you to colour correct your image per-camera, using colour temperature and tint properties.

You can enable a colour chart in your scene to aid selection, just like using a reference chart in real-world photography.

Resolution

Settings for changing rendering resolution on a per-camera basis. 

Blender School: Photographer 5x

 Photographer 5 (Introduction to lighting)

What is the Photographer addon for Blender?

At its core, Photographer adds rendering, lighting and compositing parameters that are consistent with physical lighting and photography. This can make recreating realistic scenes easier if you are familiar with photography, lighting and optics. Photographer is a must-have if you are combining Blender and real-world camera outputs. 

There are a lot of additional features, some of which are remarkable. I particularly like the Camera and Lens Post FX because you can set up realistic bloom and glow effects in just a few clicks without needing to access the compositor interface. There are more features, but I've not used them because I've never learned how they work. The next few posts will follow my journey deeper into Photographer 5.

 First, a refresher on Lighting:

There are two scientific approaches to measuring light:

Photometry: measures visible light by weighting its power according to the human eye's varying sensitivity to different colours. This is a system used by photographers and filmmakers.
Radiometry: measures the total power of light (radiant flux) across the entire electromagnetic spectrum. This is the absolute measure that isn't based on human perception.

Scale and Light
Light strength changes the apparent scale of a scene. This truism should encourage you to set up scenes that use real-world scale, as you are less likely to be bamboozled by trying to make things look realistic that are fundamentally unrealistic. 

Inverse Square Law and brightness
The brightness of a light source follows the inverse square law, so it falls off very quickly. You'll subconsiously see this in any depiction of a real-world scene. 

Example from CGCookie tutorial on lighting.

In a CGCookie tutorial, Jonathan Lampel provides a great example of how a well-crafted 3D scene can compromise realism, as the light from the room's lamps is as bright as sunlight. This would not be the case in reality.

Light intuitions
As an observer with properly functioning eyes, we handle changing light levels extremely well, to the extent that we don't even notice it happening. It makes us a poor judge of how much light there is in our environment because the light-capturing equipment in our heads is automatic, and our brain tries to filter the change so we're not distracted from survival tasks.

Blender's built-in light system

Blender uses the energy rating of lamps, measured in watts, to rate light sources. This makes lights easy to understand, but it isn't the whole story. The wattage of a physical bulb is a measure of the electrical energy used to create light. However, traditional bulbs waste a lot of energy in the form of heat, whereas Blender's lights don't simulate poor efficiency; they put all that power out in the form of visible light. The actual output is measured as Radiant Flux (Φ), also measured in watts. If you look at diode or gas discharge lamps, their rating is neither the electrical input (it's actually the equivalent input rating of a traditional bulb) nor the light power. Confusing! Therefore, light power requires a standard unit of measurement. We used Lumens. 

Lumen: the SI unit of luminous flux, equal to the amount of light emitted per second in a unit solid angle of one steradian from a uniform source of one candela.

This gets more confusing! Different colours of the same light value are perceived differently by human eyes. To measure the value of a naturally produced light, we use a Kelvin value. This is the value of a neutral substance, called a blackbody, that emits when heated to a Kelvin temperature. This is why there's a black body node in Blender. By colouring your lights in Kelvin values, you get more realistic results.

A light's lumen value describes its brightness, while its Kelvin temperature describes its colour.

And it's weirder! Sometimes light is even more complex than that: even with exact temperatures, wattage and so on, an LED lamp will only look like the sun if you stare at it directly, not at the things it illuminates. The full spectrum of an LED lamp is different, and surface materials can respond differently under two seemingly matching lights. There's also polarisation, but that only matters if you want realistic looks through sunglasses; otherwise, adding a bit of colour filtering would be enough to mask its effect.

Kelvin light temperature

Final thing: White Balance.

So this brings together two things we've covered. One, our eyes and brains make numerous adjustments, allowing us to filter out the "cast" created by the colour of light sources and perceive objects as white under standard lighting conditions.

Light sources create a cast based on the Kelvin temperature. From 2000K, we get a warm orange/yellow cast. When we get to 4000K the lighting has a neutral daylight cast (it's actually a bit yellow but our eyes filter it out), and when we get to the top-end of the range, the light cast turns blue (10,000K). While human eyes and brains do this perceptual filtering, cameras don't. In digital photography, you need to set what white looks like in the environment you are viewing. Professionals often use a white card to calibrate the white balance of their camera, although most cameras have a pretty good automatic setting.

The white balance is not an absolute thing. There are times when you want to capture the colour cast, such as when viewing a sunset, where that quality is an aesthetic element. However, there are times when you need the whites to be white, for example, an interior scene where you want to see that the walls are painted white, not yellow.

White balance controls were introduced as native features in Blender 4.3.

Next, we'll start looking at Photographer 5.

Test terrain animation

 

It's been a while since I put renders into an animation. This one was set up in about three minutes to help evaluate a bowl-shaped terrain. I added the pod and dropped some shiny materials onto it just to add some interest. 

Back on the road, again

 I'm having a catch-up with the director this evening. It's time to deliver on my commitment to improve the current service road scene, ensuring it aligns more closely with the storyboard. 

Both walls

Running with Double Blender

Blender-School Render Raw 1

I need to get back into more structured learning. I have too many urgent things to learn than I can count using my fingers. 

• I should do a minimum of three 1-hour training blocks per week.
• These blocks must include note-taking and exercises.

I think the following are a priority:

• Render Raw
• Photographer 5x
• Lens-Sim
• Hard-Ops
• Substance Painter
• Geonodes
• Geoscatter
• PBR Material and Material Generator (revision)
• Extreme PBR

More general learning:

• Environmental and terrain tutorials
• True-Assets revision

This list was pulled from the air. I may suddenly realise there's something important missing.

So to start, let's take a look at Render Raw.

Render Raw (Featuring Creative Shrimp's mini-course on colour correction)

See Render Raw's full documentation.

Basics

In Blender, outputs are generated in RAW but are then baked into a colour space for display. This baking happens through a View Transform model, such as AGX or the older Filmic. These view transforms take the Colour Gamut (colour model that handles chromacity (measures hue and colourfulness) and filter them through a transform process that we often refer to as "baking", which indicates a one-way process that can't be reversed because it loses data. If you don't use a View Transform, then your high-bit-depth output simply gets clipped as it transitions into the Closed Colour Space. It often results in blown-out images that just look bad.

Colour Gamuts set the range of colours that can be displayed. Blender uses sRGB (standard RGB) because it offers a good, easy-to-use and accurate colour presentation across various devices and formats. Note: Internally (pre-output), Blender uses the Linear Rec.709 because it's physically accurate and linear, so good for the technical aspects.

Colour Gamut (1931 CIE)

Default gamut sRGB through the AgX View Transform.

RAW is the uncompressed high bit-depth image format, such as EXR, that contains "raw" colour data. This format yields extremely large files. It's normal to use a View Transform to bake the colour data to match the expected view formats.

ACES is the Academy Color Encoding System and was designed for the film industry to provide a standard so that different creators could have consistency as they worked on each other's outputs. ACES isn't better than AgX; it has limitations like Filmic, but it is the industry standard, and sometimes consistency is better than capability when you know how to work around limitations.

In Blender 4.0 the View Transform moved from Filmic to AgX. This caused a bit of a stir because AgX tended to make outputs "pop" a bit less. However, AgX is just objectively a better and more sophisticated View Transform model. Filmic doesn't support wider gamut colour spaces, such as P3. It also has a lower dynamic range. Although, with middle-range colours and intensities, the two View Transforms provide comparable results. For more information, Christopher's 3D's excellent introduction to AgX.

In a nutshell, rendering to RAW instead of through a view transform preserves light and colour data that you can modify to enhance the look of the output. Previously, this tweaking would be done outside of Blender in a separate image processing app, such as Photoshop/Photo/Lightroom or a compositor, such as Premiere or DaVinci Resolve. For this, you'd  save your outputs in a high bit-depth format like EXR that preserves colour data.

Render Raw

It is a Blender addon that provides tweaking tools, similar to those found in external apps, within Blender and available in the viewport to preview. However, they are still applied at the end of the rendering pipeline.

Pre-grade: A change made before the render pipeline (and View Transform) as part of a scene's setup
Post-grade: A change applied to a render output, usually in the compositor

Render Raw works with both Pre and Post-grade changes as they are applied through the compositor (but under the bonnet, as you don't need to touch the compositor yourself).

Nodes and their grade position

Post-formation changes are more lossy because they are applied to pixels that have been baked out of a View Transform. They also are not protected from breaking out of the available colour/intensity. Post-formation colour tweaking allows you to achieve the colours you want; however, you need to be careful as you make your changes.

Once Render Raw is installed, you enable it through the N-panel. Its tools then appear within the panel, or under the Render tab's Colour Management panel.

N-Panel view

Transform: The View Transform, as listed above.

Presets: A set of parameter adjustments that get general effects, such as a contrast punch

Exposure: Light levels. Lower for moody, higher can look washed out. It's safer to be slightly above as you don't lose too much definition.

Gamma: Not intended for mortals. It's not an exposure setting, it's not a colour grading instrument, it's a technical setting. Leave it at 1.

Colour correction example

You'll see in this example how post-formation tweaks could filter out the flame's form and avoid AgX's "salmon" colour profile. This is why Render Raw uses both pre- and post-formation adjustments.

Starting point

See the colour in the visor highlights has clipped with artefacts on the fringes.

Colour boost is less likely to blow out colours.

Moody with saturation

Lesson takeaway: 

• No amount of colour correction tools training will tell you what looks good. I need to delve into colour theory, photography and cinematography. 
  
  
• Keep RAW for access to the source colour data and the most options for making image adjustments.
  
  
• Make Pre-formation changes to have the source colour data to work with, but Post-formation changes are sometimes just what you need.

Part two of this lesson is coming soon, although I grasp what the tool does much better now.

Back to learning, back to focused output

 I have work to do, but I make excuses to do something else. Usually, what I do is not focused and leads nowhere useful. Let's get back on track!

1) More planning and discipline... complete a training element at least twice per week. So, more Blender School!

2) No more starting something and fizzling out.  Although it is okay to abandon a project that has run its course, if you just stop every time you hit a creative roadblock, you'll never finish anything.

3) Work towards a more iterative and reflective workflow. It's been a while since I've completed a critique session. More of those!

generative Cthulhu statue 

Treading some water

 
Over the weekend, I had a play with various terrain projects. Lots of potential for a nice scene, but I still insist on moving on and limiting my output to quick sketches.

Cyberpunk tower (not mine). Amazing, but I wanted to showcase my own build work, so onwards...

Dusted off the Texas Tower and added a first round of materials

True-Vault grass and a tree. Needs a lot of dressing, but could turn out nice.

Road to progress

 
I submitted an update on the service road. Some adjustments are required, but they're in the fine details; the overall effect was favourably received.