Santa Barbara Instrument Group CCD Camera manuel d'utilisation

Operating Manual CCD Camera Models ST-7E, ST-8E, ST-9E, ST-10E and ST-1001E Santa Barbara Instrument Group 147A Castilian Drive Santa Barbara, CA 93117 Phone (805) 571- 7244 • Fax (805) 571-1147 Web :<www.sbig.com> • Email:<sbig@sbig.com>[...]

Note: This equipment has been tested and found to comply with the limits for a Class B digital device pursuant to Part 15 of the FCC Rules. These limits are designed to provide reasonable protection against harmful interference in a residential installation. This equipment generates, uses, and can radiate radio frequency energy and if not installed[...]

i Table of Contents 1. Introduction ................................................................................................................. 1 1.1. Road Map of the Documentation ............................................................................... 1 1.2. Quick Tour .................................................................[...]

ii 4.6 Connecting the older model CFW-6 filter wheel to the Camera .................................. 30 4.7 Battery Operation ............................................................................................................. 31 4.8 ST-1001E Differences .....................................................................................[...]

Section 1 - Introduction Page 1 1. Introduction Congratulations and thank you for buying one of Santa Barbara Instrument Group's CCD cameras. The model ST-7E, ST-8E, ST-9E, ST-10E and ST-1001E are SBIG's fourth generation CCD cameras and represent the state of the art in CCD camera systems with their low noise and advanced capabilities, i[...]

Section 1 - Introduction Page 2 1.2.1. CCDOPS Software Follow the instructions below to run the CCDOPS software and display and process sample images included on the distribution diskette. • Install the software onto your hard disk. For Windows this involves running the Setup.exe file on the first diskette. For Macintosh or DOS this involves copy[...]

Section 1 - Introduction Page 3 • Load up the other sample images and display them using the photo display mode. • If you find that the display is too dark or bright, try setting Auto Contras t in the display menu or adjust the background and range parameters to achieve the best display. Usually your monitor brightness and contrast want to be s[...]

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Section 2 - Introduction to CCD Cameras Page 5 2. Introduction to CCD Cameras This section introduces new users to CCD (Charge Coupled Device) cameras and their capabilities and to the field of CCD Astronomy and Electronic Imaging. 2.1. Cameras in General The CCD is very good at the most difficult astronomical imaging problem: imaging small, faint [...]

Section 2 - Introduction to CCD Cameras Page 6 transports the charge packets in a serial manner to an on-chip amplifier. The final operating step, charge detection, is when individual charge packets are converted to an output voltage. The voltage for each pixel can be amplified off- chip and digitally encoded and stored in a computer to be reconstr[...]

Section 2 - Introduction to CCD Cameras Page 7 Host Computer Clock Drivers Preamp 16 Bit A/D Micro- controller Tracking CCD Imaging CCD Shutter TE Cooler PC Interface Telescope Interface Desktop Power Supply Parallel Interface Figure 2.2 - CCD System Block Diagram As you can see from Figure 2.2, the ST-7E, ST-8E, ST-9E, ST-10E and ST-1001E are comp[...]

Section 2 - Introduction to CCD Cameras Page 8 The CCD is cooled with a solid-state a thermoelectric (TE) cooler. The TE cooler pumps heat out of the CCD and dissipates it into a heat sink which forms part of the optical head's mechanical housing. In the ST-7E and ST-8E cameras this waste heat is dumped into the air using passive radiators and[...]

Section 2 - Introduction to CCD Cameras Page 9 current, which can cause each pixel to fill with electrons in only a few seconds at room temperature even in the absence of light. By cooling the CCD, the dark current and corresponding noise is reduced, and longer exposures are possible. In fact, for roughly every 5 to 6° C of additional cooling, the[...]

Section 2 - Introduction to CCD Cameras Page 10 at the same temperature and for the same duration as the light frame with the source of light to the CCD blocked so that you get a "picture" of the dark. This dark frame will contain an image of the noise caused by dark current (thermal noise) and other fixed pattern noise such as read out n[...]

Section 2 - Introduction to CCD Cameras Page 11 people think that smaller pixels are a plus , you pay the price in sensitivity due to the fact that smaller pixels capture less light. For example, the ST-9E with its large 20 x 20 micron pixels captures five times as much light as the ST-7E and ST-8E's 9 micron square pixels. For this reason we [...]

Section 2 - Introduction to CCD Cameras Page 12 Track and Accumulate to co-add several shorter images. The dual CCD design allows the guiding CCD access to the large aperture of the main telescope without the inconvenience of off-axis radial guiders. Not only are guide stars easily found, but the problems of differential deflection between guide sc[...]

Section 2 - Introduction to CCD Cameras Page 13 Of course, once the image is stored on a computer disk, it may be transferred to another computer just like any other data file. You can copy it or send it via modem to a friend, upload it to your favorite bulletin board or online service, or store it away for processing and analysis at some later dat[...]

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Section 3 - At the Telescope with a CCD Camera Page 15 3. At the Telescope with a CCD Camera This section describes what goes on the first time you take your CCD camera out to the telescope. You should read this section throughout before working at the telescope. It will help familiarize you with the overall procedure that is followed without drown[...]

Section 3 - At the Telescope with a CCD Camera Page 16 * DEC RA Figure 3.1 Orientation of the Optical Head Viewed from Back. (Pixel 1,1 is at the upper left in this view) 3.3. Establishing a Communications Link When the CCDOPS program is initiated it will automatically attempt to establish a link to the camera. This involves identifying the type of[...]

Section 3 - At the Telescope with a CCD Camera Page 17 This preliminary step will save you much time in initially finding focus. The approximate distance behind the eyepiece tube for each of our CCD cameras is listed in Table 3.1 below: Camera Distance ST-5C ~0.66 inch ST-237/A/STV ~0.68 inch ST-6 ~0.56 i nch ST-7E/8E/9E/ST-10E ~0.92 inch ST-1001E [...]

Section 3 - At the Telescope with a CCD Camera Page 18 eyepiece and slide it back and forth to find the best visual focus, and then scribe the outside of the eyepiece barrel. The next time the CCD is used the eyepiece should be first inserted into the tube to the scribe mark, and the telescope visually focused and centered on the object. At f/6 the[...]

Section 3 - At the Telescope with a CCD Camera Page 19 3.8. Processing the Image If not done already, images can be improved by subtracting off a dark frame of equal exposure. You will typically do this as part of the Grab command although it can also be done manually using the Dark Subtract command. By subtracting the dark frame, pixels which have[...]

Section 3 - At the Telescope with a CCD Camera Page 20 Another aspect of the Focus command and its various modes is the Camera Resolution 4 setting in the Camera Setup command. Briefly, the Resolution setting allows trading off image resolution (pixel size) and image capture time while field of view is preserved. High resolution with smaller pixels[...]

Section 3 - At the Telescope with a CCD Camera Page 21 One of the reasons that SBIG autoguiders are often better than human guiders is that, rather than just stabbing the hand controller to bump the guide star back to the reticule, it gives a precise correction that is the duration necessary to move the guide star right back to its intended positio[...]

Section 3 - At the Telescope with a CCD Camera Page 22 Color imaging places some interesting requirements on the user that bear mentioning. First, many color filters have strong leaks in the infrared (IR) region of the spectrum, a region where CCDs have relatively good response. If the IR light is not filtered out then combining the three images in[...]

Section 4 - Camera Hardware Page 23 4. Camera Hardware This section describes the modular components that make up the CCD Camera System and how they fit into the observatory, with all their connections to power and other equipment. 4.1. System Components The ST-7E, ST-8E, ST-9E, ST-10E and ST-1001E CCD cameras consist of four major components : the[...]

Section 4 - Camera Hardware Page 24 Typically you would take ten 1 minute "snapshots" to produce an image that is comparable to a single 10 minute exposure except that no guiding is required. The reason no guiding is required is that with most modern telescope mounts the drift over the relatively short 1 minute interval is small enough to[...]

Section 4 - Camera Hardware Page 25 In our older camera models and in the optional relay adapter accessory, each of the relays has a Common, a Normally Open, and a Normally Closed contact. For example, when the relay is inactivated there is a connection between the Common and the Normally Closed contact. When the relay is activated (trying to corre[...]

Section 4 - Camera Hardware Page 26 used to attach to the wiper to either end of the potentiometer when the opposing relays are activated. potentiometer A B C A: Unmodified Joystick wiper B: Modified Joystick nc c no + relay A B C nc c no - relay Figure 4.3 - Joystick Modification A slight variation on the joystick modification is to build a comple[...]

Section 4 - Camera Hardware Page 27 software. Software developers can produce one package for the many users across the model line instead of different packages for each of the cameras. While the SBIG cameras have many similarities, there are also important differences between the products. Table 4.2 below highlights the differences from a system&a[...]

Section 4 - Camera Hardware Page 28 Camera CCD Used Number of Pixels Pixel Dims. Array Dimension Read Noise Full Well Capacity Tracking CCD TC-211 192 x 164 13.75 x 16 µ 2.6 x 2.6mm 12e - rms 150Ke - ST-5C TC-255 320 x 240 10 x 10 µ 3.2 x 2.4mm 20e - rms 50Ke - ST-237A TC-237 657 x 495 7.4 x 7.4 µ 4.7 x 3.6mm 15e - rms 20Ke - STV TC-237 320 x 20[...]

Section 4 - Camera Hardware Page 29 length is the focal length of the telescope or lens. Also remember that 1° = 3600 arcseconds. Read Noise - The readout noise of a CCD camera affects the graininess of short exposure images. For example, a CCD camera with a readout noise of 30 electrons will give images of objects producing 100 photoelectrons (ve[...]

Section 4 - Camera Hardware Page 30 C8, 8" f/10 LX200, 10" f/3 6 14" f/11 Camera Field of View ( arcmins) Pixel Size ( arcsecs) Field of View ( arcmins) Pixel Size ( arcsecs) Field of View ( arcmins) Pixel Size ( arcsecs) Tracking CCD 4.2x4.2 1.3x1.5 11.7x11.7 3.7x4.3 2.3x2.3 0.7x0.8 ST-5C 5.4x4.1 1.0x1.0 14.4x10.8 2.7x2.7 2.8x2.1 0.[...]

Section 4 - Camera Hardware Page 31 ST -7E/8E/9E/10E head. The phone cable connection connects to the telescope drive to adjust the telescope position when collecting images using Self-Guiding, and the short cable with three wires connects to the CFW-6. The black wire of the three-wire group mates to the brown or black wire of the CFW-6. 4.7 Batter[...]

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Section 5 - Advanced Imaging Techniques Page 33 5. Advanced Imaging Techniques With practice, you will certainly develop methods of your own to get the most from your CCD camera. In this section we offer some suggestions to save you time getting started in each of the different areas outlined below, but these suggestions are by no means exhaustive.[...]

Section 5 - Advanced Imaging Techniques Page 34 the twilight sky near the horizon or take an image of a blank wall or neutral grey card. The Kodak CCDs may have a low contrast grid pattern visible in the sky background. A flat field will eliminate this. Finding areas of the sky devoid of stars is very difficult after twilight. Therefore, you should[...]

Section 5 - Advanced Imaging Techniques Page 35 is best for critical focusing. Planet mode will result in fast digitization and download times since only a small portion of the frame is read out. In general, you should pick a binning mode that yields stars with two to three pixels full width at half maximum. This is easily measured by using the cro[...]

Section 5 - Advanced Imaging Techniques Page 36 5. Repeat steps 3 and 4 as many times as desired for all the objects you wish to image, each time choosing a set of corresponding new names for the IMAGE and TRACK files. 6. You will now create a combined flat field image for each Track and Accumulate image you captured. Invoke the Add by Track List c[...]

Section 5 - Advanced Imaging Techniques Page 37 absolutely necessary. Finally, modern drive correctors with periodic error correction ( PEC) or permanent periodic error correction ( PPEC) will ease the difficulty of achieving good results. The moral of the story is don't count on the CCD autoguider to fix all your problems. The better the driv[...]

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Section 6 - Accessories for your CCD Camera Page 39 6. Accessories for your CCD Camera This section briefly describes the different accessories available for your CCD camera. 6.1. Cooling Booster The cooling booster, which is included with the ST-9E and ST-10E, is an option for the ST-7E, ST-8E and ST-1001E. It is a small module that gets installed[...]

Section 6 - Accessories for your CCD Camera Page 40 reservoir from a significant height above it, such a 0.3 meter (12 inches). Lastly, check for leaks! When using water cooling, avoid the temptation to put ice in the water to get the camera even colder. As the cooling booster is designed, the camera will not be cooled below ambient temperature if [...]

Section 6 - Accessories for your CCD Camera Page 41 6.5. AO-7 and Lucy-Richardson Software The AO-7 is the world's only Adaptive Optics accessory for the amateur CCD market and it works only with the self guided feature of the ST-7E/8E/9E/10E. The AO-7 is essentially an electromechanical driven diagonal mirror that goes between the camera and [...]

Section 6 - Accessories for your CCD Camera Page 42 the screen, and use an exposure longer than 1/30th of a second to avoid the video refresh rate of your monitor. Darken the room, and use a brighter background than is visually optimum. For the best quality hard copy, save the files in TIFF format and send a copy of the file on a disk to a photo la[...]

Section 8 - Glossary Page 43 7. Common Problems This section discusses some of the more common problems others have encountered while using our CCD cameras. You should check here if you experience difficulties, and if your problem still persists please contact us to see if we can work it out together. Achieving Good Focus - Achieving a good focus i[...]

Section 8 - Glossary Page 44 The easiest meth od of finding objects is to use a reticule eyepiece, if the object is bright enough to see. Pull the CCD optical head from the eyepiece holder and insert a 12-20mm eyepiece, focussing the eyepiece by sliding it in and out of the eyepiece holder, not by adjusting the telescope's focus mechanism. Cen[...]

Section 8 - Glossary Page 45 8. Glossary Antiblooming Gate - When a CCD pixel has reached its full well capacity, electrons can effectively spill over into an adjoining pixel. This is referred to as blooming. Kodak CCDs with the antiblooming option can be used to help stop or at least reduce blooming when the brighter parts of the image saturate. A[...]

Section 8 - Glossary Page 46 Flat Field - A Flat Field is a image with a uniform distribution of light entering the telescope. An image taken this way is called a flat field image and is used with CCDOPS to correct images for vignetting. Focal Reducer - A Focal Reducer reduces the effective focal length of an optical system. It consists of a lens m[...]

Section 8 - Glossary Page 47 Planet Mode - Planet Mode is the most useful way to achieve focus. When you select Planet mode, a full frame is exposed, downloaded, and displayed on the computer monitor. A small window can be placed anywhere in the image area and the size of the window can be changed. Subsequent downloads will be of the area inside th[...]

Section 8 - Glossary Page 48 Sky Background - The sky background illumination or brightness is the number of counts in the image in areas free of stars or nebulosity and is due to city lights and sky glow. High levels of sky background can increase the noise in images just like dark current. For some objects deep sky filters can be used to reduce t[...]

Appendix A - Connector Pinouts Page 49 A. Appendix A - Connector ad Cables This appendix describes the various connectors and cables used with the ST- 7E/8E/9E/10E/1001E. A.1. Appendix A - Connector Pinouts Tables A1 and A2 below show the pin-outs of the Telescope and Power connectors on the ST- 7E/8E/9E. Pin Number Function 1 Chassis Ground 2 CFW-[...]

Appendix A - Connector Pinouts Page 50 the Celestron Ultima, Losmandy CG11 and Meade LX-200. You can interface these telescopes to the Telescope port with our TIC-78 (Tracking Interface Cable), or you can make your own cable. Figure A1 below shows the pinouts on these telescopes. Special Common Left Down Up Right White Black Red Green Yellow Blue N[...]

Appendix B - File Formats Page 51 B. Appendix C - Maintenance This appendix describes the maintenance items you should know about with your CCD camera system. B.1. Cleaning the CCD and the Window The design of SBIG cameras allows for cleaning of the CCD. The optical heads are not evacuated and are quite easy to open and clean. When opening the CCD [...]

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Appendix C - Capturing a Good Flat Field Page 53 C. Appendix C - Capturing a Good Flat Field This appendix describes how to take a good flat field. A good flat field is essential for displaying features little brighter than the sky background. The flat field corrects for pixel non-uniformity, vignetting, dust spots (affectionately called dust dough[...]

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Index 55 A/D converter, 8, 27 accessories, 41 adaptive optics, 40 antiblooming, 29, 45 Antiblooming Gate (def), 45 AO-7, 40 astrometric measurements, 45 Astrometry (def), 45 astrophotography, 12 atmospheric effects, 17 auto contrast, 18 Auto Grab Command, 21 autoguider, 8, 20, 23, 36, 45 Autoguider (def), 45 background parameter, 18 battery operati[...]

Index 56 focal reducer, 40 Focal Reducer (def), 46 focus Dim mode, 18, 19 fine, 17 Full frame mode, 17 Full Frame mode, 19 peak, 17 Planet mode, 17, 19, 46 Focus Command, 17, 19 focus mode, 17, 19 Focusing, 16 Frame Transfer CCDs, 6 Frame Transfer CCDs (def), 46 frost, 8 Full Frame CCDs, 6 full well capacity, 29 Full Well Capacity (def), 46 Grab Co[...]

Index 57 shutter, 8 signal to noise ratio, 22, 29 sky background, 5, 20 smoothing, 19 snapshot, 23 software, 26, 41 spectral range, 5 spectrograph, 41 Status Window, 16 Link field, 16 stellar magnitude, 19 stellar temperature, 19 super pixel, 19 taking images, 18 TE cooler, 8 TE Cooler, 7 TE Cooler (def), 48 Technical Support, 42 telescope, 10, 15,[...]