SBIG ST-8XME-C2 Class 2 CCD Camera

High Quantum Efficiency CCD Cameras

Like the ST-10XME and ST-7XME, the new ST-8XME is based upon Kodak's latest microlens technology that increases the effective QE of the CCD. The KAF-1603ME is now available for the model ST-8 cameras. This CCD features a peak QE of nearly 85%, 1530 x 1020 pixels at 9 microns square, and multiple AR coatings on the CCD window for increased light transmission and significantly reduced reflections. The ST-8XME camera also includes a TC-237H CCD with 657 x 495 pixels at 7.4 microns for self-guiding and a Remote Guiding Head Port. The ST-8XMEI is a single sensor camera with no guiding CCD, but it does include the Remote Guiding Head port. Although it is intended for industrial applications, it is also an excellent lower price alternative for astronomy where an external guider is used. Both models are available with a Class 2 or Class 1 CCD. Other than the cosmetic specifications, the Class 2 ME CCD has the same low noise and high QE as the Class 1.

For years, the model ST-8 camera was the flagship of the SBIG self-guiding models. This position was eventually taken over by the higher resolution ST-10XME and more recently by the much larger STL-11000M cameras, but the ST-8XME still has its place. At 100 inches or more of focal length, the 9 micron pixels of the ST-8XME each see about 0.7 arcseconds. It is unlikely that during typical seeing conditions where the FWHM of star images on long exposures are generally greater than 2.5 arcseconds, the smaller pixels of the ST-10XME will improve on the resolution of the ST-8XME at this focal length or longer, and while the ST-10XME will produce an image with twice as many pixels, the field of view is nearly the same. Also, the ST-8XME is well suited to TDI imaging. Alan Holmes has written an Application Note about TDI Imaging and Research applications that are perfect for the ST-8XME and ST-8XMEI cameras. TDI is particularly interesting because one can image large areas of the sky without guiding so any telescope will do. TDI stands for Time Delay Integration. Basically, one points the camera at an area of sky and turns off the telescope drive to let the stars drift across the field of view. The CCD is clocked in sync with the rate of drift and the resulting image has an exposure time equal to the amount of time it takes the stars to drift across the CCD. Depending on the focal length of the scope this can be many minutes. But there is no periodic error and no guiding error! Furthermore the image can just scroll as the sky moves past so the image file can be 1020 x 1000 or 1020 x 2000 etc. One gets a deeper image with a more sensitive CCD. In the case of the ST-8XMEI the extra QE of the microlensed CCD make it quite sensitive to dim objects and very good wide field astro images can be created with no tracking at all. All of this means the ST-8XME might be the best choice for imaging through longer focal lengths or for unguided TDI imaging at a significant savings compared to the ST-10XME.

Other than the guiding CCD and included accessories, the ST-8XME and ST-8XMEI are the same camera.

Improved Features

Large Built-In Tracking CCD: The Self-Guiding model uses the TC-237H tracking CCD which is now standard in all of our self-guiding cameras. The TC-237H array is 657 x 495 pixels at 7.4 microns. The TC-237H is 2.7X larger than the TC-211 CCD which means there is a more than double the chance you will find suitable guide stars anywhere you happen to be looking without having to hunt. In the tracking configuration, the TC-237H CCD will normally be binned 2x2 for increased sensitivity. When binned 2x2 the field of view remains 2.7X that of the TC-211 however as the pixel size is increased to 14.8 microns. The user may also use the TC-237H CCD in high resolution (unbinned) mode if desired. ThsSky software from Software Bisque automatically generates finder charts showing the correct placement of the guiding CCD field of view relative to the imaging CCD's field of view. Using this tool to plan your nights imaging is a great compliment to the self-guiding cameras. When guiding with the TC-237H tracking CCD, the imaging CCD spends 100% of its time and quantum efficiency gathering the image. You are not required to compromise by giving up half of the quantum efficiency or by making twice the exposure time as you might with other self-guiding designs.

Upgradeability: The standard ST-8XME comes with a Class 2 CCD with no column defects. The ST-8XMEI may be upgraded to a dual CCD camera for self-guiding at any time. Current owners of ST-7 and ST-8 cameras may upgrade to the ST-8XME if they already have USB electronics.

Improved Carrying and Storage Case: The ST-8XME model includes a high quality carrying and storage case made for SBIG by Pelican. The custom cut foam securely holds the camera and power supply with additional spots for accessories, cables, etc. The case is dust proof, water proof, crush proof and carries a lifetime guarantee from the manufacturer. The case is optional for the ST-8XMEI.

Optional Accessory Test Lens: To make testing of the camera easier we have designed an optional low cost test lens that screws into the t-thread front end of the camera. This is a handy accessory for learning the various camera functions in the day time if you do not have a camera lens adapter. See our Test Lens Product Announcement for more details.

Optional Accessories: The ST-8XME cameras support a variety of professional accessories. Each model contains a ROM programmed to support the CFW8A Color Filter Wheel for automatic RGB or LRGB imaging when attached to the camera. Each model also has electronic relays built-in so that the cameras can be used as autoguiders for film astrophotography or for guiding other CCD cameras. The built-in TC-237H guiding CCD in the ST-8XME model enables the use of both the AO-7 Adaptive Optics Device and the SGS Self-Guiding Spectrograph. The Self-Guiding Spectrograph was designed to give maximum resolution with 9 micron pixels. Several camera lens adapters are available from SBIG for attaching a variety of 35mm camera lenses directly to the ST-8 without the filter wheel for wide field imaging. Third party manufacturers support the ST-8XME and CFW8A color filter wheel combination with camera lens adapters as well.

Packages and Price

The ST-8XME Model uses a Class 2 ME CCD with high QE and no column defects. It includes the built-in TC-237H tracking CCD, custom carrying case, water cooling heat exchanger, relay adapter plug, relay cables for self-guiding, universal power supply, and extra software.

Each ST-8XME camera system includes the following: