---
title: currentISO
framework: avfoundation
role: symbol
role_heading: Type Property
path: avfoundation/avcapturedevice/currentiso
---

# currentISO

A constant to indicate not to specify a new ISO value, and instead set it to its current value.

## Declaration

```swift
class let currentISO: Float
```

## Discussion

Discussion A special value that you may pass as the ISO parameter of the setExposureModeCustom(duration:iso:completionHandler:) method to indicate that the caller doesn’t specify a value for the ISO property, and to instead set to its current value. note: A device may be adjusting ISO at the time of the call, in which case the value set may differ from the value of thee iso property.

## See Also

### Exposure constants

- [currentExposureDuration](avfoundation/avcapturedevice/currentexposureduration.md)