---
title: exposureTargetBias
framework: avfoundation
role: symbol
role_heading: Instance Property
path: avfoundation/avcapturedevice/exposuretargetbias
---

# exposureTargetBias

The bias to apply to the target exposure value, in exposure value (EV) units.

## Declaration

```swift
var exposureTargetBias: Float { get }
```

## Mentioned in

Enhancing your app experience with the Camera Control

## Discussion

Discussion When the device exposure mode is AVCaptureDevice.ExposureMode.continuousAutoExposure or AVCaptureDevice.ExposureMode.locked, the bias affects both metering (exposureTargetOffset), and the actual exposure level (exposureDuration and iso).  When the exposure mode is AVCaptureDevice.ExposureMode.custom, it only affects metering. This property is key-value observable.

## See Also

### Adjusting exposure compensation

- [exposureTargetOffset](avfoundation/avcapturedevice/exposuretargetoffset.md)
- [minExposureTargetBias](avfoundation/avcapturedevice/minexposuretargetbias.md)
- [maxExposureTargetBias](avfoundation/avcapturedevice/maxexposuretargetbias.md)
- [currentExposureTargetBias](avfoundation/avcapturedevice/currentexposuretargetbias.md)
- [setExposureTargetBias(_:completionHandler:)](avfoundation/avcapturedevice/setexposuretargetbias(_:completionhandler:).md)