ST9

The ST-9E is identical to the ST-7E and ST-8E cameras with the exception of the imaging CCD. The ST-9E utilizes the same patented dual sensor head design integrating one CCD for self-guiding and another CCD for imaging. In the case of the ST-9E the imaging sensor is the new Enhanced KAF-0261E detector from Kodak. The ST-9E Imaging Camera is ideal for use on long focal length scopes where a larger field of view than an ST-7E is desired, but one's budget does not allow for an ST-8E camera. Large scopes, even those with relatively fast f/ratios, have focal lengths that "waste" sensitivity of cameras using detectors with small pixels. Longer focal lengths also mean smaller fields of view given a fixed detector size. Take, for example, a C-14 at f/7, 16" SCT at f/6.3 and a 20" f/5. In all of these cases the telescopes

have focal lengths of about 98 to 100 inches. When used at 100 inches of focal length, the 9 micron pixels of the ST-7 and ST-8 cameras subtend about 0.7 arcseconds - a bit small for this focal length. So these cameras are often operated binned 2x2 at focal lengths of 100 inches or more unless the optics and seeing are rather exceptional. For the ST-8 this is no problem because the detector has 1.5 million pixels and binning 2x2 still leaves the user with a reasonable 765 x 510 pixels @ 18 microns. But binning the ST-7 2x2 yields an image that is 382 x 255 so the image size on the monitor begins to get small for this size camera. However, the ST-9E's 20 micron pixels subtend about 1.6 arcseconds per pixel at 100 inches focal length without binning. Just about perfect for typical seeing conditions. This gives the user the advantage of larger more sensitive pixels and a reasonably large image of 512 x 512. Moreover, when the FOV of the ST-9E is nearly as large as an ST-8.

Model ST-9E CCD Specifications:

CCD Kodak Enhanced

KAF-0261E (Class 1)

+ Texas Instruments TC-211

Pixel Array 512 x 512 pixels,

10.2 x 10.2 mm

Total Pixels 262,144

Pixel Size 20 x 20 microns

Full Well Capacity 200,000 e-

Dark Current 35e¯/pixel/sec at 0° C

Antiblooming Not available

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Readout Specifications

Shutter Electromechanical

Exposure 0.11 to 3600 seconds, 10ms

resolution

Correlated Double Sampling Yes

A/D Converter 16 bits

A/D Gain 2.8e¯/ADU

Read Noise 13e¯ RMS

Binning Modes 1 x 1, 2 x 2, 3 x 3

Full Frame Acquisition

(including digitization and

download) ~ 11 seconds

Fast updates for focus

(partial frame) ~1.6 seconds

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Optical Specifications (8" f/10)

Field of View 17.3 x 17.3 arcminutes

Pixel Size 2 x 2 arcseconds

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System Specifications

Cooling - standard Two Stage Thermoelectric Active Fan

Water Assist Ready

-40 degrees C from Ambient Minimum

Temperature Regulation ±0.1°C

Power 5 VDC at 1.5 amps, ±12 VDC at 0.5 amp

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110VAC desktop power supply included

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12VDC power supply optional

Computer Interface Standard Parallel Port

Computer Compatibility PC - MS-DOS, Windows 95/98/NT, Macintosh With Optional MAC SCSI adapter

Guiding Dual CCD Self-Guiding

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Physical Dimensions

Optical Head 5 inches diameter x 3 inches 12.5 cm diameter x 7.5 deep 2 pounds/0.9 Kg

CPU All electronics integrated into Optical Head, No CPU

Mounting T-Thread, 1.25" and 2" nosepieces included

Backfocus Approximately 0.9 inches

2.3 cm

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