Starlight Xpress SXV-M25C User Manual

Handbook for the SXV-M25C Issue 1 June 2004

Starlight Xpress Ltd

SXV-M25C SuperHAD 6Megapixel USB

One-Shot Colour CCD camera

User manual

Thank you for purchasing a Starlight Xpress CCD camera. We hope that you will be
very satisfied with the results.

The SXV-M25C is an advanced, very high-resolution cooled CCD camera, especially
designed for ‘One-Shot’ colour astronomical imaging. The features include a built-in,
fully programmable, USB 2 super-fast computer interface (USB 1.1 compatible), an
optional add-on autoguider output and integrated dual serial ports for filter wheel and
telescope control. The SXV-M25C uses a Sony ICX413AQ a very large ‘SuperHAD’
interline CCD, with 3040 x 2016 x 7.8uM pixels in a 23.4 x 15.6mm active area.
SuperHAD devices have excellent quantum efficiency in the visible spectrum, 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. The CCD
incorporates a ‘Bayer Matrix’ of Red, Green and Blue filters, deposited directly onto
the pixels and a downloaded image may be quickly converted into a full-colour
picture by application of the software provided.

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Handbook for the SXV-M25C Issue 1 June 2004

The USB 2 connection offers an excellent download speed, despite the very large
number of pixels to be digitised. The full-frame download time with a 2GHz machine
is approximately 16 seconds and binned 4x4 downloads take only 3 seconds, so
finding and centring are quick and easy in this mode. If you have only a USB 1.1
connection on your computer, the download time is longer, but is still quite fast at
around 30 seconds for a full resolution frame.

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.

‘Quick Starting’ your SXV-M25C system

In the shipping container you will find the following items:

1) The SXV-M25C camera head.

2) A power supply module.

3) A power supply cable.

4) An SXV guider head.

5) A cable for the guider head to camera connection.

6) An RJ11 cable for connection of the guide output to the mount.

7) A USB2 camera cable.

8) An adaptor for 2” drawtubes and M42 Pentax thread lenses.

9) A disk with the SXV-M25C control software.

10) This manual.

Optional extra items include:

1) A serial port splitter adaptor and cable for filter wheels etc.

You will also need a PC computer with Windows 98, Windows Me, Windows 2000
or Windows XP installed (NOT Windows 95 or NT4). This machine must have at
least one USB port available and at least 128 Megs of memory. If you intend to view
the finished images on its screen, then you will also need a graphics card capable of
displaying an image with a minimum of 1024 x 768 pixels and 16,000,000 colours.
The very large image format means that viewing the entire image at full resolution is
not practical, but a 1600 x 1200 monitor resolution with 32 bit colour helps
considerably. A medium specification Pentium with between 1 and 2GHz processor
speed is ideal. USB 2 PCI and PCMCIA cards are readily available for upgrading a
USB 1.1 machine, if you want to achieve the best possible performance. Please note
that USB 2.0 operates at a very high speed and cannot operate over very long cables.
Five metres of good quality cable is the maximum normally permitted. Adding one, or
more, USB 2 ‘Hubs’ in line can extend this, if necessary. USB 1.1 is more tolerant
and will often work properly over a 15 metre lead without hubs.

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Installing the USB system:

First, find a free USB socket on your PC and plug in the USB cable. If you do not
have a USB capable computer, it is normally possible to install a USB 2 card into an
expansion slot. Almost all machines manufactured after 1996 provide a pair of USB

1.1 sockets on the rear panel and either of these may be used if USB 1.1 is
satisfactory. Please note that it may be necessary to enable your USB system in the
computer BIOS (the SETUP menu which can usually be accessed at start-up). Many
BIOS systems have the ability to disable ‘Plug and Play’ devices, such as the USB
ports, so please make sure that these are enabled.

The next operation is to run the USB installer from the CD ROM provided. Insert the
CD into the computer and run the ‘InstallSXV’ file which is found in the SXV-M25C
directory. This will install the following files:

1) ‘SXV_BlockIO_M25C.inf’ in C:\Windows\Inf\

2) ‘Generic.sys’ and ‘SXVIO.sys’ in C:\Windows\System32\Drivers\

If you cannot see the directories ‘C:\Windows\Inf’ and ‘Windows\System32\Drivers’,
this will be due to the setup of your Windows Explorer software. In this case, go to
the ‘Tools’ menu, followed by ‘Folder Options’ and select ‘View’. Now select ‘Show
hidden files and folders’ and make sure that the ‘Hide file extensions for known file
types’ and ‘Hide protected operating system files’ check boxes are NOT checked.
After this, the various directories and files should be visible.

It is now time to set up the USB device. Plug the USB cable into the camera and
observe the computer screen. After a brief delay, you should see an information box,
which reports that the computer has found a device called ‘Echo2’ and is looking for
the driver. If all is well, the cycle will complete within a couple of seconds, but it is
possible that you may have to prompt the system with the location of the ‘SXVIO.sys’
file (Windows\System32\Drivers). After another brief delay, the computer should say
that it has found a new USB2.0 device and is installing a ‘Starlight Xpress USB 2.0
CCD camera’. In some cases the installation will halt after the first stage and you will
need to restart the machine, or unplug and re-plug the USB lead to initiate the second
step.

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At the end of this process, the USB interface will be installed as a ‘BlockIOClass
device’ and the camera software will be able to access it. You can confirm that the
installation is complete by checking the status of the USB devices in the Windows
‘Device Manager’ (see above). Start up the Windows ‘Control Panel’ and select
‘System’. Now click on the tab labelled ‘Device Manager’ and all of the system
devices will be displayed in a list (see above). If the installation is successful, there
will be a diamond shaped symbol labelled ‘BlockIOClass’ and clicking on the ‘+’
sign will reveal it to be a ‘Starlight Xpress USB 2.0 SXV-M25C camera driver’ or
similar. If this device is faulty, try clicking on it and selecting ‘properties’ and then
‘update driver’. Following the on screen instructions will allow you to re-select the
correct inf file (SXV_BlockIO_M25C.inf) and driver file (SXVIO.sys), which should
fix the problem.

Adding the camera control software:

Now that the USB system is installed, the camera control program can be used to
operate your SXV-M25C. Copy the camera software files from the CD and paste
them into a suitable directory, such as ‘SXVM25’ on your computer’s C: drive. Your
directory should contain the files SXV_M25C_usb.exe, SXV_M25.hlp, bwcc32.dll
and wsc32.dll

Connecting the camera:

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The camera rear panel

Connect up the power supply and switch it on. You can start the ‘SXV_M25C’
software by double clicking on the icon and you should see the main menu and image

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panel appear. If the USB connection is OK, a message box will inform you of the
‘Handle’ number for the SXVIO interface and various other version details etc. The
main program window will now be seen.

If you press the ‘Camera’ Icon button at the top left, the program will warn you that
the ‘Program Defaults’ have not been set, but pressing ‘OK’ will allow you to
continue.
The camera default settings are not important for current purposes and may be left as
the software start-up values for now, but the warning message may be removed by
selecting ‘Set program defaults’ from the ‘File’ menu and then saving the defaults
window by pressing the ‘Save changes’ button. Once the camera control panel is seen,
you are all set to take your first images!

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. There are two simple options, at least one of which is available to everyone:

1) Attach a standard ‘M42’ SLR camera lens to the SXV-M25C, using the 25mm
spacer to achieve the correct focal distance.

Or

2) Create a ‘Pin hole’ lens by sticking a sheet of aluminium baking foil over the end
of the 2” adaptor and pricking its centre with a small pin.

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Handbook for the SXV-M25C Issue 1 June 2004

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. The pin hole needs no such adjustments and will work
immediately, although somewhat fuzzily.

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 SXV_M25C software tool bar.

The camera control interface will open.

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You can now select an exposure time of 0.1 seconds, followed by pressing of the
‘Take Photo’ button.

After the exposure and download have completed (about 16 seconds) an image of
some kind will appear on the computer monitor. It will probably be poorly focused
and incorrectly exposed, but any sort of image is better than none! In the case of the
pinhole, all that you can experiment with is the exposure time, but a camera lens can
be adjusted for good focus and so you might want to try this to judge the image
quality that it is possible to achieve. With our 2 inch adaptor, most lenses come to
infinity focus at about midway through their normal focus adjustment range. The
large size of full resolution M25 images makes them difficult to visualise on most
computer screens and only about one third of the image may be visible. You can
‘scroll’ around the image using the sliders at the right and bottom edges, or select ‘Bin
high res. display’, as found in the ‘View’ menu. This reduces the displayed image to
half size and most of it will now be visible – the image data is NOT affected.

Various other exposure options are available, as can be seen in the picture of the
interface above. For example, you can ‘Bin’ the download 2x2, or more, to achieve
greater sensitivity and faster download, or enable ‘Continuous mode’ to see a steady
stream of images. The 4x4 or 6x4 binning modes give adequate resolution for finding
and offer a much faster download speed, along with a very high sensitivity.

‘Focus mode’ downloads a 128 x 128 segment of the image at high speed. The initial
position of the segment is central to the frame, but can be moved by selecting ‘Focus
frame centre’ in the ‘File’ menu and clicking the desired point with the mouse. The
focus window has an adjustable ‘contrast stretch’, controlled by the 12-16 bit slider.
The image will be normal if 16 bits is selected, while setting lower values will
increase the image brightness in inverse proportion.

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Please note that ONLY 1x1 binned images will decode to colour – the other modes
are for focusing and acquisition only.

If you cannot record any kind of image, please check the following points:

1) Ensure that the power indicator lamp is on and that the cables are properly home
in their sockets.

2) If the screen is completely white, the image may be greatly overexposed. Try a
shorter exposure time, or stop down your lens. See if covering the lens causes the
image to darken.

3) If the USB did not initialise properly, the camera start-up screen will tell you that
the connection is defective. Try switching off the power supply and unplugging the
USB cable. Now plug in the USB cable, followed by the power. This will re-load
the USB software and may fix the problem after restarting the SXV_M25C
program. Otherwise, check the device driver status, as previously described, and
re-install any drivers which appear to be defective.

4) If you cannot find any way of making the camera work, please try using it with
another computer. This will confirm that the camera is OK, or faulty, and you can
then decide how to proceed. Our guarantee ensures that any electrical faults are
corrected quickly and at no cost to the customer.

Converting your image to colour:

Once you have a recognisable image, it is quite easy to convert it to full colour. The
‘raw’ image will appear to have a fine grid distributed across it – this is the colour
filter matrix and the variations of pixel brightness encode the colour data which we
want to extract. Here is an enlarged section of a raw image:

Click on ‘Colour Synthesis’ in the main menu and you will see the synthesiser dialog.

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This includes various options for correcting the colour synthesis for variations in the
lighting conditions, filters etc. Briefly, these items perform the following functions:

1) Daylight Image? – If an unfiltered lens is used, the infra-red content of the

light will tend to produce a Green – Blue shift in the balance. A partial
correction of this bias is provided by selecting this option, but the best option
is to use an infra-red blocking filter when taking daylight shots (see 5 below).

2) Light Pollution Correction: - This option is for deep sky colour images,

where a strong colour bias is often present in the sky background. This option
attempts to return the background colour to a neutral grey.

3) Colour Smoothing Filter: - Applies a low pass filter to the colour data to

smooth out colour noise.

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.

6) Stretching: - A selection of contrast-boosting options which are preset for

various subjects.

7) Remove Background: - This option will adjust the sky background brightness

to give an optimum background level.

8) High Pass filters: - Automatically sharpen the luminance data to emphasise

fine details. Most useful for sharpening planetary images but will also increase
the noise content.

For your first test images, I suggest that you turn on the Anti-Alias option and
possibly the ‘Daylight Image’ option.

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