Sony SXV-M5C user manual Star

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Handbook for SXV-M5C Issue 1 August 2004

box and cables are available as an accessory and may be chained in series with the autoguider cable, when the guider is in use, or may be used on its own.

The two serial connections are in the form of standard RS232 PC style plugs and provide TX, RX and Ground connections at RS232 levels. Access is via commands sent through the USB connection and, at the time of writing, is limited to any serial controls that are provided by the SXV software. It is expected that many more functions will be added as the software is upgraded.

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STAR 2000

The SXV-M5C may be used with our patented self-guiding system ‘STAR 2000’. This can greatly ease the process of recording long exposure deep-sky images.

Using ‘STAR 2000’ self-guiding with the SXV-M5C

How S.T.A.R. 2000 works:

S.T.A.R. 2000 is a unique and patented method of automatically controlling your telescope drives, while capturing a long exposure image with your Starlight Xpress CCD camera. Unlike off-axis guiding devices and dual-CCD self-guiding cameras, S.T.A.R. 2000 can guide on almost any object, which is visible within the CCD frame! You have the entire CCD field of view to choose from and can even select a slowly moving target, such as a comet nucleus, or asteroid, to guide on during the exposure.

The principle of S.T.A.R. is based on the special CCD structure of the chips used in our SXV_M5, M7 and M9 cameras and it cannot be used with ‘full frame’ CCDs, such as the popular Kodak devices. It is also incompatible with our HX516 camera. The M5, M7 and M9 use ‘Interline Interlaced’ CCD ch ips, which are constructed with each pixel split into two vertically stacked halves. Each half can be ‘read out’ independently, so it is possible to integrate a long exposure on one field of half pixels, while the other field is read out at short intervals and the data used for guiding the telescope. Half way through the exposure, we can read out the contents of the integrating field, swap fields, and integrate the rest of the exposure on the other field. This preserves the best image resolution and eliminates ‘aliasing’ effects.

To give a fast guider update rate, the guiding field is read out as an 80x40 window around the guide object, while the unused lines are ‘dumped’. Using this technique, it is possible to feed corrections to the telescope drive as often as one every second when guiding on a fairly bright star (typically about mag. 11). The sub-pixel guiding accuracy of S.T.A.R. 2000 will give you tightly defined, round star images, however long the exposure time that you use!

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Contents SXV-M5C ‘Quick Starting’ your SXV-M5C system Connecting upInstalling the software Recording your first image Page Page Correcting and refining the colour image Decoding the image to colourEnhancing your image Getting the image onto the CCD Astronomical Imaging with the SXV-M5CPage Page Achieving a good focus Taking your first astronomical image Processing the deep-sky image Page Taking pictures of the planets Processing a planetary image Other features of SXVM5C ‘Slew & Sum’ imaging Taking and using a flat field Using the built-in serial ports Accessory portsStar What you need Starting to guide Page Exposure times and image calibration Using the add-on autoguiderPage Page Page Removing Dust Camera maintenanceDealing with condensation ProcedurePixel size CCD sizeQE peak Spectral responseConditions of Guarantee