Environment & image-based lighting
Light a whole 3D scene from a single sky or HDRI: soft fill from every direction, plus the reflections that read on shiny surfaces.
Wrapping the scene in an image, or in a procedural sky, lights it without placing individual lights. Bright parts of that image push light into the scene, and the whole image appears in reflections on metal, glass and glossy materials. This is image-based lighting (IBL), and it pairs with a few Light lights for accents.
What the environment contributes
Two things at once.
Ambient light. Soft illumination arriving from all directions. A bright sky lifts the tops of objects, a warm ground bounces colour back up underneath, and shadowed areas stop going dead black.
Reflections. The environment image is what appears mirrored in shiny surfaces. A polished sphere reflects the whole room; a rough surface reflects a blurred, smeared version of it.
Rougher materials get blurrier reflections automatically, so brushed metal and chrome both read correctly from the same environment. Material response is set per surface. See Materials.
A clean studio HDRI gives flattering, predictable lighting in seconds. Outdoor HDRIs bring strong directional sun plus coloured sky fill. Swapping the environment changes the entire mood of a render faster than any other single edit.
Using an HDRI or a procedural sky
Add an environment with the Environment node. mode picks where the light comes from.
Image, the default. Feed it an HDRI loaded through Image, or leave the input empty and
colorbecomes a flat environment colour.Sky, a procedural atmosphere rather than a gradient.
sun_elevationandsun_azimuthplace the sun;airis Rayleigh scattering, so more of it is a bluer sky;dustis the Mie haze around the sun;ozonedeepens the blue;altitudeandground_albedoset the observer height and the bounce off the ground.Uniform, constant radiance in every direction. The white-furnace case, for checking a material in isolation.
The environment also appears as the backdrop behind objects, so the sky you light with is the sky you see. Turn visible_in_background off to keep the lighting and composite over your own background instead.
| Parameter | Type | Default | What it does |
|---|---|---|---|
mode | String | "Image" | Image: use a texture (solid color gradient, HDRI). Uniform: constant radiance in every direction (white-furnace / IBL). Sky: procedural atmosphere. One of: Image, Uniform, Sky. |
channels | Field or Color Field | — | Environment input — Field (HDRI / gradient / procedural) or Field(Record) with hdri / irradiance / radiance channels |
color | Color | rgba(0.15, 0.15, 0.20, 1.00) | Flat environment color when no map is connected (Image), or the constant radiance (Uniform) |
sun_elevation | Number | 45 | Sun elevation above horizon (degrees) |
sun_azimuth | Number | 180 | Sun azimuth (0=North, 90=East, 180=South, 270=West) |
air | Number | 1 | Rayleigh (molecular air) density — higher = bluer, denser sky |
dust | Number | 1 | Mie (dust/haze) density — higher = hazier sun glow |
ozone | Number | 1 | Ozone absorption — higher = deeper blue sky |
altitude | Number | 0 | Observer height above sea level (metres) |
ground_albedo | Number | 0.300 | Ground reflectance — affects atmospheric bounce light |
rotation | Number | 0 | Rotate environment around Y axis |
intensity | Number | 1 | Environment lighting intensity |
tint | Color | rgba(1.00, 1.00, 1.00, 1.00) | Color tint applied to the environment |
visible_in_background | Boolean | true | Show environment as viewport/render background |
fog_enabled | Boolean | false | Enable scene-level volumetric fog |
fog_density | Number | 0.020 | Fog density — extinction per world unit at the fog height |
fog_height | Number | 0 | World height (Y) at which fog has full density |
fog_height_falloff | Number | 0.100 | Density falloff per unit of altitude above the fog height (0 = uniform) |
fog_color | Color | rgba(1.00, 1.00, 1.00, 1.00) | Fog color — what the fog scatters under white light |
fog_anisotropy | Number | 0.200 | Scattering direction: 0 = even glow, + = glow toward camera-facing lights |
fog_ambient | Number | 0.100 | Ambient fog brightness floor from the environment light |
Rotation, intensity and tint
rotationspins the environment around the Y axis to aim the brightest part, a sun or a window, at the place highlights and shadows should fall from. It also rotates what appears in reflections.intensityscales how much light the environment throws. Down to let accent lights dominate, up for a bright, airy look.tintpushes the overall colour of the lighting warm or cool without editing the source image.
Rotation is the key-light direction. Before adding any extra lights, rotate the environment until the shading on the subject already reads well, then add lights only for the accents it is missing.
Volumetric fog and light shafts
Scene-level volumetric fog lives on the Environment node. It is a real medium filling the whole scene, catching the light and letting lights carve visible shafts through it. Turn on fog_enabled, which is off to start with, and every light in the scene glows through the haze.
fog_densitysets how thick the air is, as extinction per world unit.fog_heightandfog_height_falloffsettle the fog low like ground mist and thin it out with altitude. Set the falloff to 0 for even fog everywhere.fog_colortints what the fog scatters under white light.fog_anisotropybiases the glow toward the camera, so lights facing you bloom into soft shafts (god rays) rather than an even wash. At 0 the glow is even.fog_ambientkeeps fog in shadow from going pure black.
Fog reads the scene's lights directly, so a spotlight cutting through it gives volumetric beams with no extra setup. This is atmosphere that fills the room. For a fog or cloud shape you build and place, use a Volumes instead.
Linear working space
All lighting maths stays in a single linear working space and converts to the display look at the very end, so environment light, Light lights and materials all add up correctly. Bright skies push values well above white, which is what produces punchy highlights and bloom. The final film-style look comes from the renderer's tone mapping, set on the canvas. See Colour management.
By default, reflections come from the environment and the scene's lights. For mirror-accurate object-to-object reflections, turn on rt_reflections on the Render Settings node (see Post effects and The render node).