Santa Barbara Instrument Group ST-7E manuale d’uso

Operating Manual CCD Camera Models ST-7E, ST-8E and ST-9E Santa Barbara Instrument Group 1482 East Valley Road • Suite 33 PO Box 50437 Santa Barbara, CA 93150 Phone (805) 969- 1851 • Fax (805) 969-4069 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 4.5. Modular Family of CCD Cameras ............................................................................ 26 4.6 Connecting the older model CFW-6 filter wheel to the Camera .................................. 30 4.7 Battery Operation ............................................................................................................[...]

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 and ST-9E 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, including Kodak&apo[...]

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 Contrast 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 se[...]

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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 horizontal register of pixels. This register collects a line at a time and then 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 a[...]

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 and ST-9E are completely self contai[...]

Section 2 - Introduction to CCD Cameras Page 8 using passive radiators and a small fan, making the design and operation of the heads simple and not inconvenienced by requirements for liquid recirculation cooling. The ST -9E includes SBIG's secondary TE/Liquid cooling booster. Since the CCD is cooled below 0°C, some provision must be made to p[...]

Section 2 - Introduction to CCD Cameras Page 9 have a single stage TE cooler and a temperature sensing thermistor on the CCD mount to monitor the temperature. The ST-9E has a supplemental second stage cooling booster with water cooling as an option (described in section 6.1). The microcontroller controls the temperature at a user-determined value f[...]

Section 2 - Introduction to CCD Cameras Page 10 minute, eliminating the many "hot" pixels one often sees across the image, which are simply pixels with higher dark current than average. 2.4.4. Flat Field Images Another way to compensate for certain unwanted optical effects is to take a "flat field image" and use it to correct fo[...]

Section 2 - Introduction to CCD Cameras Page 11 (High = 9µ 2 pixels, Medium = 18µ 2 pixels, Low = 27µ 2 pixels). When binning is selected the electronic charge from groups of 2 by 2 or 3x3 pixels is electronically summed in the CCD before readout.. This process adds no noise. Binning should be used if you find that your stellar images have a hal[...]

Section 2 - Introduction to CCD Cameras Page 12 readout noise less. It is handy when no connection to the telescope drive is possible. SBIG is proud to make self-guiding available to the amateur, making those long exposures required by the small pixel geometry of the ST-7 and ST-8 easy to achieve! 2.5. Electronic Imaging Electronic images resemble [...]

Section 2 - Introduction to CCD Cameras Page 13 purpose is simply to make a record or catalog the image file for easy identification, a dot matrix or laser printer should be fine. Inkjet printers are getting very good, though. 2.6. Black and White vs. Color The first and most obvious appearance of a CCD image is that it is produced in shades of gra[...]

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Section 3 - At the Telescope with a CCD Camera Page 15 3. At the Telescope with a CCD Came ra 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 drow[...]

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 0.660 inch ST-237/STV 0.680 inch ST-6 0.560 inch ST-7E/8E/9E 0.920 inch Table 3.1 - Camera [...]

Section 3 - At the Telescope with a CCD Camera Page 18 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 depth of focus is only 0.005 inch, so focus is critical. An adapter may be necessary to allow the [...]

Section 3 - At the Telescope with a CCD Camera Page 19 using the Dark Subtract command. By subtracting the dark frame, pixels which have higher dark current than the average, i.e., "hot" pixels, are greatly suppressed and the displayed image appears much smoother. Visibility of faint detail is greatly improved. The CCDOPS program also sup[...]

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 3 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 reaso ns 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 positi[...]

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 and ST-9E CCD cameras consist of four major components: the CCD Sensors and Pr[...]

Section 4 - Camera Hardware Page 24 required is that with most modern telescope mounts the drift over the relatively short 1 minute interval is small enough to preserve round star images, a feat that even the best telescope mounts will not maintain over the longer ten minute interval. The Track and Accumulate software does allow correction of the t[...]

Section 4 - Camera Hardware Page 25 the relay is inactivated there is a connection between the Common and the Normally Closed contact. When the relay is activated (trying to correct the telescope) the contact is between the Common and the Normally Open contacts. If your hand controller is from a relatively recent model telescope it probably has fou[...]

Section 4 - Camera Hardware Page 26 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 complete joystick eliminator as shown in Figure 4.4 below. The only difference between this and the previous [...]

Section 4 - Camera Hardware Page 27 Camera A/D Resolution Temperature Regulation Electromechanical Shutter/Shutter Wheel/Vane Electronic Shutter ST-5C 16 bits Closed Loop Shutter Wheel 0.01 second ST-237 12 bits Closed Loop Shutter Wheel 0.01 second STV 10+2 bits Closed Loop Shutter Wheel 0.001 second ST-6 16 bits Closed Loop Vane 0.01 second ST-7E[...]

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 16µ 2.6 x 2.6mm 12e - rms 150Ke - ST-5C TC-255 320 x 240 10 x 10µ 3.2 x 2.4mm 20e - rms 50Ke - ST-237 TC-237 640 x 480 7.4 x 7.4µ 4.7 x 3.6mm 15e - rms 20Ke - STV TC-237 320 x 200 14[...]

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 5 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 0.5x0.5 [...]

Section 4 - Camera Hardware Page 31 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 Battery Operation The ST-7E/8E/9E can be operated off of a 12 volt car or marine battery using a the optional 12V power supply or using a power inverter. We have used the Radio Shack model 22-132[...]

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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 5.4. Taking a Good Flat Field If you find that flat field corrections are necessary due to vignetting effects, CCD sensitivity variations, or for more accurate measurements of star magnitudes, try either taking an image of the twilight sky near the horizon or take an image of a blank wall or neutral g[...]

Section 5 - Advanced Imaging Techniques Page 35 functions except when you are in Full Frame Focus Mode. It will then automatically switch to Low Resolution Mode. If you further select Planet Mode for focusing, the camera will switch back to High Resolution on the selected box area. The small pixel size, is best for critical focusing. Planet mode wi[...]

Section 5 - Advanced Imaging Techniques Page 36 what alignment operations were done to the individual components of IMAGE to achieve the end result. In the following discussions this track list file will be referred to as TRACK. 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 corre[...]

Section 5 - Advanced Imaging Techniques Page 37 mechanical problems, though. You still need a good polar alignment and a rigid mount between the guide scope and the main scope or you need to use an off-axis guider, with all its inherent difficulties. A good declination drive, free of backlash, is desirable although not absolutely necessary. Finally[...]

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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 is an option for the ST-7E and ST-8E, is a small module that gets installed inside the back comp[...]

Section 6 - Accessories for your CCD Camera Page 40 ambient temperature if ambient temperature water is used. If colder water is used, the head may fog or frost up, depending on the dew point. . The exposed electronics inside the ST-7/8 will get wet, and corrode. The hoses will start dripping condensation, and you will have a mess. Keep the ice for[...]

Section 6 - Accessories for your CCD Camera Page 41 6.6. SGS - Self-Guided Spectro graph The SGS Self Guided Spectrograph takes the tedium out of spectroscopy by allowing you to image and guide the source on the tracking CCD while acquiring its spectra on the imaging CCD. No more hunting around to place the object on the slit! With the SGS you can [...]

Section 6 - Accessories for your CCD Camera Page 42 6.8. SBIG Technical Support If you have any unanswered questions about the operation of your CCD camera system or have suggestions on how to improve it please don't fail to contact us. We appreciate all your comments and suggestions. Additionally if you are interested in writing software supp[...]

Section 7 - Common Problems 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 [...]

Section 7 - Common Problems Page 44 following suggestions. The easiest method 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 telescop[...]

Section 7 - Common Problems Page 45 cause A/D Timeout and other parallel errors. Refer to you computer manual for how to use the BIOS Setup utility to configure your parallel port.[...]

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Section 8 - Glossary Page 47 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 48 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 49 can be changed. Subsequent downloads will be of the area inside the box resulting in a much faster update rate. Quantum Efficiency - Quantum Efficiency refers to the fractional number of electrons formed in the CCD pixel for a given number of photons. Quantum Efficiency is usually plotted as a function of wavelength. Re[...]

Section 8 - Glossary Page 50 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 the sky background level. Seeing - Seeing refers to the steadiness and the clarity of the atmosphere during an observing session. TE Cooler - The TE Cooler is a Thermal Electric [...]

Appendix A - Connector Pinouts Page 51 A. Appendix A - Connector ad Cables This appendix describes the various connectors and cables used with the ST-7E/8E/9E. 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-8 Pulse/AO-[...]

Appendix A - Connector Pinouts Page 52 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 None 5 6 7 4 3 Telescope Port Pin Modular Phone Wire Color Hand Controller Button Figure A1 - CCD[...]

Appendix B - File Formats Page 53 B. Appendix C - Maintenance This appendix describes the maintenance items you should know about with your CCD camera system. B.1. Cleaning the CCD an d 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 55 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 57 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 58 flip, 19 focal length, 30 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 [...]

Index 59 separations, 19 setup, 15 SGS-Self Guided Spectrograph, 41 sharpen, 19 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[...]