Something not right?

Costly effects are set to Live, such as GTAO (ambient occlusion), volumetric light, projector beams and soft shadows. A large or Retina window at full preview resolution, projector lights worn by avatars, or a crowded region also cost frames.

Set the costly effects to Render only. Lower Preview resolution on the Settings tab, and turn on the Low quality live switches.

A render layers 16 frames at twice the size of the window, which takes 10–20 seconds. With Full detail on, the viewer can first wait up to 30 seconds for textures to load.

This is normal. Stop or Esc cancels a render.

Switching styles and effects many times builds up memory in Apple's graphics driver.

Restart the viewer.

There was not enough free memory. The note on the picture says so.

Quit apps you are not using: right-click the app in the Dock and choose Quit. Preview with large pictures open can hold a lot. Or turn off Full detail, or render at the window's size.

The memory ran out partway through.

Quit apps you are not using: right-click the app in the Dock and choose Quit. Preview with large pictures open can hold a lot. Or turn off Full detail, or render at the window's size.

The textures had not finished loading.

Wait a moment before you render, or turn on Full detail.

That is by design:

• Effects set to Render only appear only in the render.
• Backlit scenes meter the exposure afresh and can come out darker.
• Depth of field is sampled through the lens.

Set an effect to Live to preview it.

An EXR holds the light untoned. It is meant for HDR editors, not as a finished picture.

Open it in an editor that handles HDR, or render PNG, JPEG or TIFF for a finished picture.

Unless Render directly to disk is on, a render is kept only until you download or share it. Closing it asks first.

Use Download or Share, or turn on Render directly to disk on the Render tab.

The snapshot window cannot show Luminous's effects. The viewer tells you so when it opens.

Use Render in the Luminous sidebar.

Most effects only show with the right light or settings:

• Lens flare and anamorphic streaks need very bright light in the frame.
• Projector beams need projector lights.
• GTAO (ambient occlusion) only shows in ambient light and shade, not under lamps unless On lamps is set.
• Soft shadows need shadows turned on in Preferences.
• Enhanced reflections need glossy surfaces.
• The tone curve settings are greyed out under old (non-PBR) skies.

Hover over an effect's name in the viewer to see a picture of what it does. The same pictures are on the front page.

Use Pause scene, or set the animation speed to 0.

Alpha sorting is render-only. The live view draws alpha the way Second Life does.

The Move the camera tick is on.

Untick it to apply styles without moving the camera.

Second Life keeps your personal sky across logins.

The Region's sky button brings the region's own sky back.

Luminous needs Apple silicon and macOS 15 Sequoia or later. Memory: 16 GB recommended. Macs with less than 16 GB get a one-time warning at start-up. There is no version for Intel Macs.

Download Luminous.

Choose Help › Report a Bug in Luminous, with the log ticked. After a crash it ticks the log from the session that crashed by itself. You can also report it on this site.