Advertisement
Quick Links
Handbook for the SXVR-M25C
Issue 1 June 2009
The SXVR-M25C one-shot colour CCD camera
Thank you for purchasing a Starlight Xpress CCD camera. We hope that you will be
very satisfied with the results.
The SXVR-M25C is an advanced, high-resolution one-shot colour cooled CCD
camera, especially designed for astronomical imaging. It is a third generation version
of the very popular SXV-M25C and incorporates many substantial improvements and
extra features. These include a built-in, fully programmable, USB 2 super-fast
computer interface, an autoguider control port and output and optional integrated dual
serial ports for filter wheel and telescope control. It also includes a CCD temperature
monitoring circuit which provides regulated set-point cooling of the chip and a
substantial reduction in overall size.
1
Advertisement
Related Manuals for Starlight Xpress SXVR-M25C
Summary of Contents for Starlight Xpress SXVR-M25C
- Page 1 Issue 1 June 2009 The SXVR-M25C one-shot colour CCD camera Thank you for purchasing a Starlight Xpress CCD camera. We hope that you will be very satisfied with the results. The SXVR-M25C is an advanced, high-resolution one-shot colour cooled CCD camera, especially designed for astronomical imaging.
- Page 2 Handbook for the SXVR-M25C Issue 1 June 2009 The SXVR-M25C uses a Sony ICX453AK ‘Super HAD’ progressive scan CCD, with 3032 x 2016 x 7.4uM pixels in a 23.5 x 15mm active area. Super HAD devices have excellent quantum efficiency, with a broad spectral response peaking at around 60% in the green, and an extremely low dark current, well below that of any comparable CCD currently available.
- Page 3 CD into the computer and wait for Windows Explorer to open with the list of folders on the ROM. Now find the SXVR-M25C folder and run the SETUP.EXE file that it contains – this will initiate the self-install software which will guide you through the process of installing the SX camera software (SXV_M25C_usb.exe) onto...
- Page 4 ‘BlockIOClass’ and clicking on the ‘+’ sign will reveal it to be a ‘Starlight Xpress USB 2.0 SXV-M25C BlockIO camera driver’. If this device shows as faulty, try clicking on it and selecting ‘properties’ and then ‘update driver’.
- Page 5 There are two simple options, one of which is available to everyone with a sheet of aluminium baking foil: 1) Attach a standard ‘M42’ SLR camera lens to the SXVR-M25C, using the 26mm spacer to achieve the correct focal distance.
- Page 6 Handbook for the SXVR-M25C Issue 1 June 2009 2) Create a ‘Pin hole’ lens by sticking a sheet of aluminium baking foil over the end of the adaptor and pricking its centre with a small pin. If you use a normal lens, then stop it down to the smallest aperture number possible, (usually F22), as this will minimise focus problems and keep the light level reasonable for daytime testing.
- Page 7 Handbook for the SXVR-M25C Issue 1 June 2009 Point the camera + lens or pinhole towards a well-lit and clearly defined object some distance away. Now enter the ‘File’ menu in the SXV_M25C software and click on ‘SX camera interface’. Select an exposure time of 0.1 seconds and press ‘Take Photo’.
- Page 8 Handbook for the SXVR-M25C Issue 1 June 2009 Here is a small enlarged section of a daylight image which may be similar to your test image taken with a 50mm camera lens The visible grid encodes the colour information within the image data and will now be used to decode the red, green and blue image planes into a colour picture.
- Page 9 Handbook for the SXVR-M25C Issue 1 June 2009 4) Apply Anti-Alias: - Runs a special filter over the colour data to remove coloured artefacts around sharp edges. This is especially useful for cleaning up erratically coloured star images. 5) IR Filter Used? – Sets the colour balance to allow for the loss of infra-red content when using an IR blocking filter.
- Page 10 Handbook for the SXVR-M25C Issue 1 June 2009 There is every reason to expect that the image will be reasonably well colour balanced, but if it is not, you can adjust the colour in the ‘Set Colour Balance’ dialog box (Under ‘Colour’ in the main menu).
- Page 11 ‘crispness’. At this point, you will have a working knowledge of how to take and process an SXVR-M25C image. It is time to move on to astronomical imaging, which has its own, unique, set of problems!
- Page 12 SCT into an F2 wide field astrograph and the latest versions (type III at the time of writing) will fully illuminate the chip of the SXVR-M25C. The hyperstar optics make a very fast, wide-field system which is ideal for large nebulae etc.
- Page 13 Handbook for the SXVR-M25C Issue 1 June 2009 In the case of the SXVR-M25C and a 2 arc seconds per pixel resolution, we get F = 0.0074 * 205920 / 2 = 664mm For a 200mm SCT, this is an F ratio of 664 / 200 = F3.32, which is rather less than can be achieved with the Meade converter and appropriate extension tube.
- Page 14 CCD, so that these defects are largely removed when the dark frame is subtracted from the light frame. The SXVR-M25C CCD is quite different from those used in other brands of camera and generates an extremely low level of dark...
- Page 15 ‘kill’ any hot pixels with your processing software. In SXVR-M25C, the ‘Median filter’ can do this, but other software (e.g. Maxim DL) will provide a ‘hot pixel killer’ that can be mapped to specific locations in the image, or methods such as ‘Sigma combine’...
- Page 16 Handbook for the SXVR-M25C Issue 1 June 2009 Relatively little nebulosity is visible at this time, but it will be revealed later. If you zoom in on the raw image, you will see that it has the regular grid of brighter and darker pixels, caused by the Bayer matrix filter grid on the CCD.
- Page 17 Handbook for the SXVR-M25C Issue 1 June 2009 The image should now look quite impressive and I hope that you are pleased with your first efforts! In many cases, a ‘Normal’ contrast stretch will give a good result, but may ‘burn out’...
- Page 18 Taking pictures of the planets: The SXVR-M25C has a large CCD with 6 million pixels and so it is not well suited to planetary imaging, where a small CCD is ideal. However, it can be used if you accept the relatively large amount of wasted image area, or use a sub-frame download.
- Page 19 Handbook for the SXVR-M25C Issue 1 June 2009 such as ‘Img23, Img24….’ and will be found in the ‘Autosave’ directory (or a sub- directory of Autosave, set up in the program defaults menu). The exposure time needed for good planetary images is such that the image histogram has a peak value at around 200 and does not extend much above 220 (Ignore the major peak near zero, due to the dark background).
- Page 20 If ‘active high’ inputs are needed, or a very low control voltage drop is essential, then you will need to add a Starlight Xpress ‘relay box’ between the guider output and the input to the mount. Please contact your local distributor if a relay box is required.
- Page 21 The autoguider installed on a 70mm refractor guide ‘scope in the author’s garden (the camera shown is the older SXVF version, but the connections are the same). To use the autoguider, please proceed as follows: 1) Having started the SXVR-M25C software, open the autoguider control panel by clicking on the autoguider menu button.
- Page 22 Handbook for the SXVR-M25C Issue 1 June 2009 The autoguider control panel with a guide star selected 2) Press the ‘Start’ button and a series of 1 second exposure guider images will begin to appear in the picture frame. If the images look too dim, use the ‘Stretch Image’...
- Page 23 ********************************************************************* Using the built-in serial ports The SXVR-M25C incorporates two fast serial ports for use with external accessories. The ports are available on 5 pins of the 18 way connector that is provided for the autoguider and may be accessed by plugging in a ‘serial port divider box’. The divider 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.
- Page 24 Using 2x2 binning, you can considerably improve the sensitivity of the SXVR-M25C without losing a great deal of resolving power, so you may like to use this mode for finding faint deep-sky objects. Other binning modes (3x3 and 4x4) are available and will further increase the image brightness and reduce its resolution.
- Page 25 Handbook for the SXVR-M25C Issue 1 June 2009 internal coating of matt white paint, which is placed over the objective of the telescope to provide an evenly illuminated surface. These can work well, but I prefer a simpler method, as follows: Most imaging sessions begin or end in twilight and so the dusk or dawn sky can provide a distributed source of light for a flat field.
- Page 26 5mA per output. This socket may be used for telescope control if the SXVR-M25C is employed as an autoguider, but is primarily intended to be the control output for the optional add-on autoguider camera head, available for use with the SXVR-M25C.
- Page 27 7) Replace all the camera parts in reverse order and the job is done. Dealing with condensation: The SXVR-M25C is designed to avoid condensation by minimising the volume of air trapped within the CCD cavity and by preventing moisture ingress. This normally works very well, but storage of the camera in a humid location can lead to the trapped air becoming moist by diffusion through the optical window mounting thread etc.
- Page 28 Handbook for the SXVR-M25C Issue 1 June 2009 ********************************************************************* Alternative Software Although we hope that you will be satisfied with our ‘SXV_hmf_usb’ software, other companies are offering alternative programs with more powerful processing functions. One of these is programs is ‘AstroArt’ by MSB software. You can purchase...
-
Page 29: Conditions Of Guarantee
Issue 1 June 2009 Dear Observer, Thank you for purchasing a Starlight Xpress CCD Imaging System. We are confident that you will gain much satisfaction from this equipment, but please read carefully the accompanying instruction manual to ensure that you achieve the best performance that is capable of providing.