SBIG Camera with AO (SBIG Gen 2)

For this driver, please select SBIG w /AO on the Setup tab.

Note:  There are two versions of this plug-in driver.  SBIG w/AO is used for the newer camera series such as STX and STXL.  SBIG w/AO Leg (Legacy) is used for the older cameras such as dual chip ST series and STL series. The two drivers are mostly the same but accommodate differences between the older and newer cameras, including differences in their shutter functions.  The software will notify you upon connect if you choose the wrong version.

When using an AO adaptive optics autoguiding accessory with Generation 2 "SBIG Universal" drivers, set the Camera Model selector to SBIG w/ AO.

For Generation 3 cameras such as Aluma, with or without AO accessory, please select SBIG Gen 3. For Generation 2 "SBIG Universal" cameras without AO please select SBIG Universal.

Important:  If an SBIG filter wheel is connected via the camera, you must set the Filter selection to SBIG AO w/FW. Do not use SBIG Universal.

This plug-in driver will work with the AO-7, AO-8, AO-8T, AO-L, and AO-X adaptive optics units, and all USB/Ethernet cameras that support these devices. This includes STT, STXL, and STX cameras and the older ST-7 series and STL series cameras that have USB interfaces.  

The latest version of the SBIG camera drivers are required. You can download them from

When you are using the AO control, the Guide Tab is not used.  The Dual Chip Mode selector can turned on or off; however, all guiding commands are performed through the SBIG AO Control window. Do not try to use Guide tab features while actively AO guiding.  One advantage of using the Dual Chip Mode is that the Locate mode exposures will appear in MaxIm DL.  

Although the Guide Tab is not used during AO guiding, please note that mount control configuration options are set using Guide tab Settings / Control Via.

For Ethernet connection, select Ethernet and enter the correct IP Address for the camera. The IP Address is ignored when connecting to a USB camera. To connect to a camera using USB, simply select the camera name from the Connect To dropdown.

Guider ABG affects the anti-blooming control for the autoguider CCD only (supported by older guide heads with TC-211 or TC-237 sensors only). Normally it is turned off. Anti-blooming for the main CCD is determined by the type of CCD chip installed in the camera.

Setting Binning Mode to Off-chip can be useful when a non-anti-blooming CCD chip is installed (older ST and STL models only). When enabled, it causes any binning to be performed after the CCD chip has been read (normally, binning is done inside the CCD chip before readout). Selecting this option results in slightly higher readout noise but reduces blooming. This control has no effect for anti-blooming CCD chips, and has no effect for 1:1 binning. You can also set Binning Mode to Spectroscopy. In this mode, the main sensor can be binned Nx1 to Nx3, where N ranges from 1 to 255.

The Guide Chip setting is used to select between the internal guide chip and the separate Remote Guide Head that is available as an option for many SBIG camera models. Select the Internal setting to use the guide chip that is built in to the main camera body. Select External Remote to use a separate "guide head".

Important Note: Some SBIG cameras contain interline CCD sensors that can be electronically shuttered, allowing them to achieve shorter exposures than frame-transfer chips, where the exposure duration is limited by the speed of the shutter. Unfortunately, the camera electronics behave differently for short exposures than for longer exposures, producing different bias patterns in the camera images. To successfully calibrate images from these cameras, bias frames cannot be used to calibrate images whose duration is shorter than .12s. These short duration images must be dark subtracted using a dark frame of the same duration as the light frame. Similarly, dark frames exposed for less than .12s cannot be scaled to match light exposures of a longer duration. For longer exposures, all of the calibration options work normally.

Please see SBIG AO Control for full details on operating an AO unit.

Availability of this feature depends on Product Level.