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# maximumExtendedDynamicRangeColorComponentValue

The current maximum color component value for the screen.

```
var maximumExtendedDynamicRangeColorComponentValue: CGFloat { get }
```

## Discussion

If no content on screen provides extended dynamic range (EDR) values, the value of this property is `1.0`. If any content onscreen has requested EDR, the value may be greater than `1.0`, depending on the capabilities of the display hardware and other conditions. Only rendering contexts that support EDR can use values greater than `1.0`.

When the value changes, [`didChangeScreenParametersNotification`](/documentation/AppKit/NSApplication/didChangeScreenParametersNotification) is posted.

## See Also

  <doc://com.apple.documentation/documentation/QuartzCore/CAMetalLayer/wantsExtendedDynamicRangeContent>


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