Environments

The environment is one of the most important elements in your renders. It controls two things:

1. What you see behind your model - The background of your image
2. How your scene is lit - Environment lighting illuminates your model and creates reflections on shiny surfaces

Think of the environment as an infinitely large sphere surrounding your entire scene (also called a sky dome or environment map in other software). Whatever image or color you set as the environment wraps around everything, providing both a backdrop and a light source.

A scene lit by an HDRI environment. Notice how the environment provides both the background and realistic lighting with natural reflections.

Finding Environment Settings

Open the Environment tab in the Rayscaper window to access all environment controls. The available options change depending on which environment type you select.

The Environment tab with HDRI selected.

Basic Controls

Before choosing an environment type, there are two important toggles that apply to all environments:

Enabled

Turns the environment on or off completely. When disabled:

• The background becomes pure black
• No environment lighting reaches your scene
• Only explicit lights (point lights, spotlights, etc.) illuminate your model

Environment Enabled

The environment provides background and lighting.

Environment Disabled

Black background, no environment lighting (only explicit lights work).

Tip

Disabling the environment is useful when you want complete control over lighting using only placed lights, or for dramatic dark renders with selective illumination.

Transparent

Makes the background transparent while keeping the environment lighting. Your model is still lit by the environment, but the background becomes an alpha channel instead of showing the environment image.

Normal Background

The environment is visible behind the model.

Transparent Background

The background is transparent (shown as checkered in viewers that support it).

Tip

Use transparent backgrounds when you plan to composite your render onto a different background in Photoshop, Figma, or other image editing software. The PNG file will include alpha transparency.

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Environment Types

Rayscaper offers three ways to create your environment: Color, HDRI, and Sky. Each serves different purposes and offers different levels of control.

Color Environment

The simplest option - a solid color that fills the entire background. This creates perfectly uniform lighting from all directions.

White

A white background - clean and professional for product shots.

Light Blue

A light blue tint adds subtle color to the lighting.

Best for: Product photography, catalog images, clean studio-style renders, or when you want complete control over the background color.

The Color environment settings.

Color Settings

Setting	Description
Environment Color	Click the color swatch to choose any background color.
Power	Controls brightness. Higher values make both the background and lighting brighter. Start with 1.0 and adjust as needed.

Tip

For classic product shots on white, set the color to pure white and increase Power to 1.0-1.5. This creates soft, even lighting that’s flattering for most objects.

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HDRI Environment

HDRI (High Dynamic Range Image) environments use real photographs of the world to light your scene. Because these images capture actual lighting conditions - including the sun, sky, buildings, and reflections - they produce incredibly realistic results with minimal effort.

Indoor

An indoor HDRI creates warm, ambient interior lighting.

Outdoor

An outdoor HDRI provides natural daylight with sky reflections.

Studio

A studio HDRI with controlled lighting - perfect for product shots.

Best for: Architectural visualization, product renders that need to look “in context,” any scene where realism matters.

How to Use an HDRI

1. Select HDRI as the environment type
2. Click Open… to browse for an HDR file
3. Adjust rotation and power as needed

Rayscaper supports .hdr and .exr file formats - the standard formats for HDR images.

Tip

You can also drag and drop HDRIs directly from the Asset Browser onto the render viewport to quickly set them as your environment.

Note

HDRIs are different from regular photos (JPG/PNG). A typical photo only stores 256 brightness levels, but HDRIs store thousands, capturing everything from deep shadows to the blinding sun. This extended range is essential for realistic lighting - regular JPG or PNG images won’t light your scene correctly.

Where to Get HDRIs

Poly Haven and ambientCG offer hundreds of free, high-quality HDRIs covering everything from outdoor landscapes to indoor studios. All their HDRIs are CC0 (public domain), so you can use them in any project.

HDRI Settings

Setting	Description
Rotation	Rotates the HDRI around the vertical axis (0-360 degrees). Use this to position the sun or brightest area where you want it, or to change reflection angles.
Power	Scales brightness. If your scene is too bright or too dark, adjust this value.

Tip

When choosing an HDRI, consider the mood you want. A sunny outdoor HDRI creates harsh shadows and warm tones. An overcast sky gives softer, more diffuse lighting. A studio HDRI with softboxes is perfect for product shots.

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Sky Environment

Sky environments generate realistic atmospheric effects procedurally - no external image files needed. These are especially useful for outdoor architectural renders where you need a convincing sky that matches your lighting.

Nishita (Midday)

Midday sun with clear blue sky.

Nishita (Sunset)

Low sun creates warm, golden lighting.

Hosek/Wilkie

Accurate sky colors, especially near the horizon.

Preetham

Fast and simple sky for quick previews.

Best for: Outdoor scenes, architectural visualization, any render where you need precise control over sun position and sky appearance.

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Sky Models Explained

Rayscaper offers three procedural sky models, each with different features and use cases.

Preetham

The simplest and fastest sky model. It produces a reasonable sky color based on sun position and atmospheric haze, but lacks some of the subtlety of the more advanced models.

When to use: Quick previews, when render speed matters more than sky accuracy, or for stylized/non-photorealistic renders.

Preetham has minimal settings - just turbidity and power.

Setting	Description
Turbidity	Atmospheric haze from 1 (crystal clear) to 10 (very hazy). Low values give deep blue skies; high values create washed-out, milky skies.
Power	Overall brightness multiplier.

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Hosek/Wilkie

An improved sky model that’s more physically accurate than Preetham, especially for colors near the horizon. It accounts for how light bounces off the ground back into the sky.

When to use: Most outdoor renders where you want a convincing sky but don’t need a visible sun disk.

Hosek/Wilkie adds ground albedo for more accurate horizon colors.

Setting	Description
Turbidity	Atmospheric haze (1-10).
Ground Albedo	How reflective the ground is (0-1). This affects sky color near the horizon - a bright ground (like snow) reflects more light back up, brightening the lower sky.
Power	Overall brightness multiplier.

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Nishita

The most physically accurate sky model, featuring a visible sun disk. It simulates how sunlight scatters through Earth’s atmosphere, including effects from air molecules (Rayleigh scattering), dust particles (Mie scattering), and ozone absorption.

When to use: Realistic outdoor renders, golden hour/sunset scenes, whenever you need a visible sun in the sky.

The Nishita sky model has the most options, giving you full control over the sun and atmosphere.

Nishita Settings

Setting	Description
Turbidity	Atmospheric haze (1-10). Lower = clearer.
Ground Albedo	Ground reflectivity (0-1). Affects horizon colors.
Sun Disk	Toggle visibility of the sun in the sky.
Sun Size	Angular diameter in degrees. The real sun is about 0.53 degrees. Larger values create a bigger, softer sun disk.
Sun Intensity	Brightness of the sun disk specifically.
Sun Elevation	Height above horizon (-90 degrees to +90 degrees). 0 degrees = sunrise/sunset, 90 degrees = noon.
Sun Rotation	Compass direction (0-360 degrees). Controls where the sun appears on the horizon.
Altitude	Simulated camera altitude in kilometers. Higher altitudes = darker, more saturated sky (like being on a mountain).
Air Density	Controls blue color intensity (Rayleigh scattering). Lower values = less blue.
Dust Density	Controls haze near horizon (Mie scattering). Lower values = clearer horizon.
Ozone Density	Controls subtle blue/purple shifts. Usually leave at 1.0.
Power	Overall brightness multiplier.

Tip

For a realistic sunset, set Sun Elevation to 0-10 degrees and increase Turbidity to 4-6. This creates the warm, orange glow associated with golden hour photography.

Syncing with SketchUp Sun

If you’re working on an architectural project where the sun position matters, you can have Rayscaper’s Nishita sky automatically follow SketchUp’s sun position. This is especially useful when:

• You’ve already set up shadows in SketchUp for a specific time of day
• You want to quickly compare different sun positions using SketchUp’s shadow settings
• You need the rendered sun to match SketchUp’s shadow studies

To enable SketchUp sun tracking:

1. Go to Extensions > Rayscaper > Use SketchUp Sun for Nishita Sky
2. The Nishita sky’s sun will now follow SketchUp’s shadow settings

Adjusting SketchUp’s shadow time automatically updates the Nishita sky’s sun position in real-time.

When tracking is enabled, you’ll see a checkmark indicator in the Environment editor, and the Sun Elevation and Sun Rotation sliders will be disabled (since they’re controlled by SketchUp).

Note

This feature only affects the Nishita sky model. If you switch to a different sky type (Hosek/Wilkie or Preetham), the tracking won’t apply. The tracking also persists with your SketchUp model, so it will be remembered when you reopen the file.

Tip

You can use both “Use SketchUp Sun for Directional Light” and “Use SketchUp Sun for Nishita Sky” together. This creates a directional light that matches the sun disk in your Nishita sky, giving you both realistic sky lighting and controllable shadow intensity.

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Practical Tips

Choosing the Right Environment Type

Scenario	Recommended Environment
Product shots on clean background	Color (white or light gray)
Architectural exterior with realistic sky	Nishita Sky
Quick outdoor previews	Preetham or Hosek/Wilkie Sky
Interior scenes	HDRI (choose one matching your window lighting)
Highly realistic renders	HDRI (real-world lighting is hard to beat)
Compositing onto custom background	Any environment + Transparent enabled

Common Workflows

Product Photography Style:

1. Use Color environment with white
2. Set Power to 1.0-1.5 for bright, even lighting
3. Enable Transparent if you need to composite later

Outdoor Architecture:

1. Use Nishita Sky for maximum realism
2. Set Sun Elevation to match your desired time of day
3. Adjust Sun Rotation to control shadow direction
4. Fine-tune Turbidity for sky clarity

Interior Scenes:

1. Use an HDRI that matches what would be visible through windows
2. Consider “overcast” or “cloudy” HDRIs for softer lighting
3. Adjust Power so the environment doesn’t overpower your interior lights

Note

The environment works together with your placed lights. For interior scenes, you’ll often want to reduce environment Power and rely more on placed lights for the main illumination.