---
title: threshold
framework: realitykit
role: symbol
role_heading: Instance Property
path: realitykit/bloomoptionscomponent/threshold
---

# threshold

The brightness threshold for bloom activation.

## Declaration

```swift
var threshold: Float
```

## Discussion

Discussion Only pixels with luminance values above this threshold will contribute to the bloom effect. The value is typically in the range [0.0, 1.x]: 0.0 makes all pixels contribute to bloom 1.0 standard threshold for HDR content (default) >1 only very bright highlights will bloom Higher thresholds create more selective bloom that only affects the brightest elements in the scene.

## See Also

### Configuring the bloom effect

- [strength](realitykit/bloomoptionscomponent/strength.md)
- [blurRadius](realitykit/bloomoptionscomponent/blurradius.md)