| The ST-7XMEI Special is a CCD camera only (without the separate built-in self-guiding detector that comes with the dual-detector ST-7XME). However, the ST-7XMEI can be upgraded to a dual-chip self-guiding camera at any time, simply by having SBIG add a guiding detector to the camera body. In addition, the ST-7XMEI has a remote guiding head port that allows you to use an existing smaller SBIG CCD camera, such as an ST-402XME, as a guider for long exposure imaging. SBIG also makes an optional #RGH Remote Guiding Head that can used to guide the ST-7XMEI using an off-axis guider or separate guide scope. The imaging detector is the new enhanced 765 x 510 pixel KAF-0402ME Class 2 detector without anti-blooming. This Kodak imaging chip has microlens technology for much higher quantum efficiency (QE) across the UV to IR spectrum than previous detectors. The high QE makes the ST-7XMEI perfect for imaging deep space objects such as dim galaxies and emission nebula. Peak QE occurs very near the H-alpha emission line at 656 nm, making this camera extraordinarily sensitive at this photographically important wavelength. It could be said that the ST-7XMEI was "made" for capturing H-alpha. Previously, this level of QE was achievable only through the process of thinning the detector wafer and illuminating the image sensor from the backside. However, thinned and back-illuminated CCDs are very expensive to make and buy. With the KAF-0402ME, similar performance to a back-illuminated CCD is achieved with lower dark current and superior cosmetic specifications in a full frame front illuminated detector. Peak quantum efficiency is almost 85%, making this camera the most sensitive in its class. In order to provide the largest full well capacity for linear response scientific measurements and the widest dynamic range for imaging, the ST-7XMEI does not have built-in antiblooming (ABG). Kodak classifies their imaging detectors according to the number and type of “defects" found on the chip. CCD Point, Cluster, and Column Defects are defined in the “Astronomical Terms" section above left. The Class 2 chip of the ST-7XME has no more than 10 point defects in its entire 390,150 pixel imaging area, no more than 4 cluster defects, and no column defects. The point and cluster defects of the ST-7XMEI are easily removed from an image during processing. Carefully guided exposures (using an off-axis guider and illuminated reticle eyepiece, or separate guiding CCD) up to one hour are possible with the ST-7XMEI, enabling a standard 8" Schmidt-Cassegrain to capture images showing 19th magnitude stars from typical background observing sites. Pixel binning modes (1x1, 2x2, 3x3) allow the user to match the pixel size to various focal lengths ranging from long focal length refractors and SCT's to short focal length camera lenses. TDI (Time Delay Integration) imaging is also possible with the ST-7XMEI. Professional astronomers performing sky surveys or asteroid searchs often build instruments that employ TDI with a CCD. This powerful imaging technique not only gives good results, but it can be done with a very simple telescope system. In essence, the telescope is fixed in position, without a motor drive in operation. As the stars drift across the CCD, the CCD is clocked at exactly the right rate to keep the accumulating charge underneath the star’s image until the star reaches the edge of the CCD, and the readout register. The camera includes a mechanical shutter, 16-bit analog to digital (A/D) converter, regulated temperature control, and has all of the electronics integrated into the CCD head. Communication to your PC is through new high speed electronics and a high speed USB interface. Data transfer rates are up to 420,000 pixels per second, allowing a full frame download in less than 1 second. The standard cooling configuration is a single stage thermoelectric cooler with an active fan and a newly designed heat exchanger. The camera body includes an inlet and outlet for water circulation should the user desire to maximize the cooling performance for hot climates. Typical cooling without water assist is -35° C from ambient (-30° C minimum). With water assist, the cooling increases to a typical -45° C. Even without water cooling, the new single-stage cooling design offers similar performance to previous two-stage cooling with much less current draw than a two-stage cooler. It is therefore less demanding on battery capacity when operating in the field. A circulating water pump and tubing are available as optional accessories. The camera body has the above-mentioned Remote Guide Head port for using an external guider. There’s a new I²C accessory port that adds bi-directional communication capability for the coming development of a new family of "smart" accessories. A standard accessory port is also provided to maintain compatibility with the customer's existing telescope interface cables and backwards compatibility with SBIG’s existing accessories – such as the CFW8 color filter wheel, AO-7 adaptive optics system, etc. The camera body has rack handles that make for easier and safer handling of the camera, particularly in cold weather when wearing gloves; a high-speed USB interface port; a user-rechargeable desiccant plug (there’s no need to return the camera to the factory for frosting problems); an internal shutter for automatic dark frames; a 2" nosepiece (a 1.25" nosepiece is optional); a T-thread ring for attaching to T-mount photo accessories; a 1/4"-20 thread side plate for tripod mounting; a 15-foot USB cable (third party USB extenders with a CAT5 cable are available for cable runs up to 300 feet); an adapter plug for the telescope interface cable; a telescope interface cable for autoguiding; and a universal 90-240VAC power supply with a remote on/off switch. You also get a CD-ROM containing full working versions of SBIG's CCDOPS version 5 camera control software, Software Bisque's CCDSoft Version 5 image processing/camera control software, and Software Bisque's TheSky version 5, level II, with telescope control for Windows. All operating manuals are on the CD-ROM. A custom designed hard carrying case with pre-cut foam is available as an option. While the software supplied with this camera is designed for use with a Windows-based PC, SBIG can also supply software to let Apple Macintosh owners control the camera. The software is available free from SBIG upon request to any new SBIG camera purchaser with proof of purchase. Simply send SBIG a copy of your invoice with the camera serial number and request the EquinoX Planetarium Software with SBIG Camera Control. The EquinoX software requires a Apple Macintosh computer (G3, G4 or G5), OS X 10.2 or later, 30MB of free RAM, and 92MB of hard disk space. The software can control all SBIG ST-series cameras and Ethernet cameras. OS X drivers for the cameras are also required and can be downloaded from SBIG at no charge. Detector specifications are as follows: Imaging Detector: Kodak KAF-0402ME, Class 2.
Pixel Array: 765 x 510 pixels.
Pixel Size: 9 x 9 microns.
Total Pixels: 390,150.
Full Well Capacity: ~100,000e-.
Dark Current: 1e-/pixel/second at 0 degrees C. Readout specifications are as follows: Shutter: electromechanical.
Exposure: 0.11 to 3600 seconds, 10ms resolution.
Correlated Double Sampling: yes.
A/D conversion: 16 bits.
A/D gain: >2.3e-/ADU.
Read noise: 15e- RMS.
Binning modes: 1x1, 2x2, 3x3.
Pixel digitization rate: up to 420,000 pixels per second.
Full frame acquisition: ~1 second. Optical specifications with 8" f/10 (2000mm focal length) scope are as follows: Field of view: 12 x 8 arc minutes.
Pixel size: 0.9 x 0.9 arc seconds.
Limiting magnitude: magnitude 14 in one second.
Limiting magnitude for 3 arc second FWHM stars: magnitude 18 in one minute. System specifications are as follows: single stage thermoelectric, active fan, water assist ready, -35° C from ambient typical (-45° C from ambient typical with water assist).
Temperature regulation: +/-0.1 degree C.
Power requirements: 5 VDC at 1.5 amps, +/-12 VDC at 0.5 amp desktop power supply included.
Computer interface: USB.
Computer compatibility: Windows 95/98/NT/2000/Me/XP. Physical specifications are as follows: Optical head: measures 5 inches diameter x 3 inches deep (12.5 cm diameter x 7.5 cm deep), weighs 2 pounds/0.9 Kg.
CPU: no separate CPU required, all electronics integrated into optical head.
Supplied mounting methods: T-thread, 2" nosepiece.
Back focus needed: 0.92"/2.3 cm.
|
Printer friendly version
Email page link to a friend
Do you have a question about this product?
