Handbook for the SXVF-H36 Issue 1 August 2007 Starlight Xpress Ltd SXVF-H36 CCD camera user manual Thank you for purchasing a Starlight Xpress CCD camera. We hope that you will be very satisfied with its performance. The SXVF-H36 is a very large format, highresolution cooled CCD camera, especially designed for astronomical imaging. The SXVF-H36 uses a Kodak KAI16000 Interline CCD, with 4008 x 2672 pixels in a 36.1mm x 24.05mm active area.
Handbook for the SXVF-H36 Issue 1 August 2007 Please take a few minutes to study the contents of this manual, which will help you to get the camera into operation quickly and without problems. I am sure that you want to see some results as soon as possible, so please move on to the ‘Quick Start’ section, which follows. A more detailed description of imaging techniques will be found in a later part of this manual.
Handbook for the SXVF-H36 Issue 1 August 2007 A rear view, showing the input and output connectors Connect the miniature 4 way power plug to the socket on the rear of the camera and screw the retaining ring into place. The LED on the rear of the camera will light a dim yellow. The other connections should not be attached until after the software has been installed. Installing the software: Switch on the computer and allow it to ‘boot up’.
Handbook for the SXVF-H36 Issue 1 August 2007 update will usually result in a tendency for white spots and streaks to appear in your images. You now need to set up the camera control defaults (shown above), as follows: Start SXV-Hmf by clicking on the icon and select the ‘File’ menu. Now select ‘Set program defaults’ and a window, which contains the various software settings, will appear.
Handbook for the SXVF-H36 Issue 1 August 2007 Recording your first image: We now have the camera and computer set up to take pictures, but an optical system is needed to project an image onto the CCD surface. You could use your telescope, but this introduces additional complications, which are best avoided at this early stage.
Handbook for the SXVF-H36 Issue 1 August 2007 Point the camera + lens or pinhole, towards a well-lit and clearly defined object some distance away. Now click on the camera icon in the toolbar of the SXV-H36 software and the camera control panel will appear (see above). Select an exposure time of 0.1 seconds and press ‘Take photo’. After the exposure and download have completed (between 8 and 10 seconds) an image of some kind will appear on the computer monitor.
Handbook for the SXVF-H36 Issue 1 August 2007 then decide how to proceed. Also check on our web site to see if there are any updates or information about your camera software that might help. The message board might prove useful to ask for help with getting your camera operating properly. Our guarantee ensures that any electrical faults are corrected quickly and at no cost to the customer.
Handbook for the SXVF-H36 Issue 1 August 2007 Astronomical Imaging with the SXVF-H36 1) Getting the image onto the CCD: It is essential to set up a good optical match between your H36 and your telescope. The H36 has a very large CCD area and so many of the popular ‘SCT’ ‘scopes are unable to provide good quality star images over the large chip.
Handbook for the SXVF-H36 Issue 1 August 2007 Because of the large CCD size used in the H36, field vignetting and field curvature will be a problem with many general purpose telescopes. The larger SCTs and many of the new ‘APO’ refractors will not suffer so badly from this issue, but you may have to compromise on vignetting and usable field size when imaging with a less highly corrected instrument.
Handbook for the SXVF-H36 Issue 1 August 2007 Taking your first astronomical image: I will assume that you are now set up with a focused camera attached to a telescope with an operating sidereal drive. If so, you are now in a position to take a moderately long exposure of some interesting deep-sky astronomical objects. As most drives are not very accurate beyond a minute or two of exposure time, I suggest that you find a fairly bright object to image, such as M42, M13, M27 or M57.
Handbook for the SXVF-H36 Issue 1 August 2007 Processing the deep-sky image: Below you will see typical examples of a dark frame and an uncalibrated raw image of M16. A typical 5 minute dark frame exposure.
Handbook for the SXVF-H36 Issue 1 August 2007 Warm pixels in a small portion of the raw image The isolated nature of the warm pixels in an SXVF-H36 image permits you to use several different methods of removing them from your raw images. Subtracting a dark frame is the most commonly used means of removing the warm pixels, but is not necessarily the best or most effective method.
Handbook for the SXVF-H36 Issue 1 August 2007 Warm pixels removed by the application of a 3x3 median filter A second option is to run a 3x3 ‘Median’ filter on the image. This simple method will remove isolated hot pixels and replace them with the median value of the pixels adjacent to them. The isolated nature of the warm pixels allows the median filter to work very well and most imagers will be quite happy with the results of this simple procedure.
Handbook for the SXVF-H36 Issue 1 August 2007 is done by using a ‘statistical’ summing technique, such as median or sigma combining, then the warm pixels will be removed altogether. This method needs more powerful image processing than is available in SXV_Hmf, but both AstroArt and Maxim DL can do it. The result of applying a median filter and contrast stretch to the raw image Another thing to try is the summing several images for a better signal to noise ratio.
Handbook for the SXVF-H36 Issue 1 August 2007 A deep image of the Deer-Lick galaxy group by Rick Krejci Although I have concentrated on the use of a telescope for deep-sky imaging, do not forget that you have the option of using an ordinary camera lens for impressive widefield shots! A good quality 200mm F3.5 lens with an infrared blocking filter will yield very nice images of large objects, such as M31, M42, M45 etc.
Handbook for the SXVF-H36 Issue 1 August 2007 below the image from light leakage in the CCD structure. To minimise this, keep the image brightness down with an ND filter or aperture stop, so that the exposure time is not less than about 0.5 seconds. A H-alpha nebula filter often gives excellent results.
Handbook for the SXVF-H36 Issue 1 August 2007 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 read-out noise will become dominant. About 30 seconds is a reasonable minimum. Now go to the ‘Multiple Exposure Options’ and select a number of exposures to take.
Handbook for the SXVF-H36 Issue 1 August 2007 diffuser needs to be added to the telescope. An ideal material is Mylar plastic draughting film, obtained from an office supplies warehouse. It is strong and water resistant and can be easily replaced if damaged. Stretch a piece of the film loosely across the aperture of your telescope and point the instrument high in the sky, to avoid any gradient in the light near the horizon.
Handbook for the SXVF-H36 Issue 1 August 2007 Using the built-in serial ports The SXVF-H36 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.
Handbook for the SXVF-H36 Issue 1 August 2007 The autoguider installed on a 80mm refractor guide ‘scope in the author’s garden To use the autoguider, please proceed as follows: 1) Having started the SXVF-H36 software, open the autoguider control panel by clicking on the autoguider menu button.
Handbook for the SXVF-H36 Issue 1 August 2007 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’ slider to increase its contrast and brightness until the noise begins to be visible. 3) If you haven’t focused the guider lens or ‘scope, move the mount until a bright star is visible on the guider image and then adjust the focus until it is as sharp as possible.
Handbook for the SXVF-H36 Issue 1 August 2007 If the stars are not circular, you may need to alter the guiding parameters, or investigate the rigidity and drive performance of your mount. A lot of information can be deduced by watching the behaviour of the guide star in the guider frame. If it is continually moving between two locations, either side of the green cross, then the RA or Dec pixels per second value is set too low. The higher these values are set, the gentler the guiding becomes.
Handbook for the SXVF-H36 Issue 1 August 2007 2) Remove the two M3 screws from the camera back plate and ease the plate out of the camera body. You may need to press down with a finger on the USB socket while pulling up on the camera barrel to overcome the friction. 3) Withdraw the body cylinder and unscrew the two long spacer pillars from the heat sink plate assembly. 4) The entire camera electronic assembly can now be lifted away from the camera front barrel and the CCD will be readily accessible.
Handbook for the SXVF-H36 Issue 1 August 2007 6) Before re-assembly, make certain that the inside surface of the front window is also clean, and then carefully replace the camera front barrel and screw it into place. (If the heat sink seal is disturbed, renew it with fresh compound before reassembling). 7) Replace all the camera parts in reverse order and the job is done.
Handbook for the SXVF-H36 Issue 1 August 2007 ********************************************************************* Some details of the camera and the CCD characteristics CCD type: Kodak KAI 16000 interline CCD imager. CCD size: Active area 36.3 x 24.2mm Pixel size: 7.4 x 7.4uM Number of pixels: 16,085,120 QE peak: approx. 52% at 500nM Spectral response: Dark signal: Typically 0.01 e per sec at 10C body temperature Power consumption: 220v / 110v AC @ 12 watts max.
Handbook for the SXVF-H36 Issue 1 August 2007 Dear User, 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. As with most sophisticated equipment a certain amount of routine maintenance is necessary to keep the equipment operating at its optimum performance.