ICameraV3Offset Property |
Namespace: ASCOM.DeviceInterface
OFFSET VALUE MODE: The current offset value.
OR
OFFSETS INDEX MODE: Index into the Offsets array for the current camera offsetException | Condition |
---|---|
InvalidValueException | When the supplied value is not valid. |
PropertyNotImplementedException | When neither OFFSETS INDEX mode nor OFFSET VALUE mode are supported. |
NotConnectedException | If the device is not connected |
DriverException | An error occurred that is not described by one of the more specific ASCOM exceptions. Include sufficient detail in the message text to enable the issue to be accurately diagnosed by someone other than yourself. |
This is an optional property and can throw a PropertyNotImplementedException if Offset is not supported by the camera.
The Offset property is used to adjust the offset setting of the camera and has two modes of operation:A driver can support none, one or both offset modes depending on the camera's capabilities. However, only one mode can be active at any one moment because both modes share the Offset property to return the offset value. Client applications can determine which mode is operational by reading the OffsetMin, OffsetMax and Offset properties. If a property can be read then its associated mode is active, if it throws a PropertyNotImplementedException then the mode is not active.
If a driver supports both modes the astronomer must be able to select the required mode through the driver Setup dialogue.
During driver initialisation the driver must set Offset to a valid value.
Please note that ReadoutMode may in some cases affect the offset of the camera; if so, the driver must be ensure that the two properties do not conflict if both are used.
This is only available in Camera Interface Version 3 and later.