We are aware of an issue at this time when setting ISO values lower than 400. If the ISO value is 125, 150 or 200 you may experience a blue/green colour cast to the images, especially in bright or sunny conditions.
We have identified the issue and will shortly be releasing a firmware update to address this issue. In the meantime, please set you iSTAR unit's ISO value to no lower than ISO 400.
The firmware update will be announced here as soon as it's available: http://support.nctechimaging.com/forums/21897927