Sony SXV-M5C user manual Other features of SXVM5C ‘Slew & Sum’ imaging

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Handbook for SXV-M5C Issue 1 August 2004

more natural look to the image, as too large a radius and power tends to outline edges with dark or bright borders.

As a finishing touch, the application of a Median filter or a Weighted Mean Low Pass filter can be useful to smooth out the high frequency noise after a strong Unsharp Mask.

As with deep-sky images, it is advantageous to sum planetary images together to improve the signal to noise ratio. In this case, the ‘averaging’ option should always be used, or the result is likely to exceed the dynamic range of the software and saturate the highlights. Aligning the images is always something of a problem, as there are rarely any stars to use when imaging the planets, but Jupiter’s satellites can be useful reference points. Otherwise, you will have to find a well-defined feature on the planet, or estimate where the centre of the disk is located. Some more sophisticated software can automatically align planetary images, but I do not find it especially difficult to do by eye.

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Other features of SXV_M5C

‘Slew & Sum’ imaging:

The SXV-M5C can be used in an automatic image-stacking mode, called ‘Slew & Sum’. The camera is set to take several sequential exposures, which are automatically ‘slewed’ into alignment and then summed together by the software. This mode can help to overcome a poor RA drive by summing images that have exposure times shorter than the drive error period. The resulting image has more noise than a single exposure of the same total length, but this method of imaging is still an effective way of making long exposures.

To take an S&S image, go to the camera interface window and select an exposure time for one image of the sequence. Do not use a very short exposure time, as the

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Contents SXV-M5C Connecting up ‘Quick Starting’ your SXV-M5C systemInstalling the software Recording your first image Page Page Decoding the image to colour Correcting and refining the colour imageEnhancing your image Astronomical Imaging with the SXV-M5C Getting the image onto the CCDPage 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 Accessory ports Using the built-in serial portsStar What you need Starting to guide Page Using the add-on autoguider Exposure times and image calibrationPage Page Page Camera maintenance Removing DustProcedure Dealing with condensationQE peak CCD sizePixel size Spectral responseConditions of Guarantee