- Qt 3D Studio
- Best Practices
- HDR Bloom Tonemap
- Qt 3D Studio 2.8 Manual

# HDR Bloom Tonemap

The HDR bloom tonemap effect provides two features:

- Adjust the gamma and exposure of the high-dynamic range rendered content to achieve the image quality you want.
- Apply an adjustable bloom effect to very bright areas (like the sun glinting off a car).

In the image below, the effect is applied in the right picture.

## Properties

Property | Description
--- | ---
Gamma | Affects the non-linear curve of the lighting. Higher values increase the exposure of mid tones, lightening the image (and decreasing the contrast). A value of `1.0` causes no adjustment to the image.
Exposure | A linear multiplier on the lighting, brightening, or darkening the image overall. A value of `0.0` causes no adjustment to the image.
Bloom threshold | Lighting greater than this value blooms. A value of `1.0` corresponds to white in the original render result. Lowering this value causes more areas of the rendered scene to bloom; at a value of `0.0` everything in the scene blooms.
Bloom falloff | Adjusts the amount of bloom. Lower values result in stronger bloom effect; higher values make the effect more subtle.

## Usage

To disable bloom and use only the tone mapping, set Bloom falloff to a sufficiently high value, like `999`.