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Related Manuals for Santa Barbara Instrument Group ST-7E
Summary of Contents for Santa Barbara Instrument Group ST-7E
- Page 1 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>...
- Page 2 • Consult the dealer or an experienced radio/TV technician for help. Shielded I/O cables must be used when operating this equipment. You are also warned, that any changes to this certified device will void your legal right to operate it. CCDOPS Manual for ST-7E/ST-8E/ST-9E Third Revision December 1999...
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Page 3: Table Of Contents
Introduction ...1 1.1. Road Map of the Documentation ...1 1.2. Quick Tour...1 1.2.1. CCDOPS Software ...2 1.2.2. CCD Camera ...3 Introduction to CCD Cameras...5 2.1. Cameras in General ...5 2.2. How CCD Detectors Work...5 2.2.1. Full Frame and Frame Transfer CCDs ...6 2.3. - Page 4 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 ...31 Advanced Imaging Techniques ...33 5.1. Lunar and Planetary Imaging...33 5.2. Deep Sky Imaging ...33 5.3. Terrestrial Imaging ...33 5.4.
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Page 5: 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's new Blue Enhanced E series of CCDs. -
Page 6: Ccdops Software
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 copying the contents of the floppy disk to a folder or directory on your hard disk. -
Page 7: Ccd Camera
• 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. -
Page 9: Introduction To Ccd Cameras
Section 2 - Introduction to CCD Cameras 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 objects. -
Page 10: Full Frame And Frame Transfer Ccds
2.2.1. Full Frame and Frame Transfer CCDs In the ST-7E, ST-8E and ST-9E, the CCD is read out electronically by shifting each row of pixels into a readout register at the Y=0 position of the CCD (shown in Figure 2.1), and then shifting the row out through an amplifier at the X=0 position. - Page 11 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 contained. Unlike our previous products, the ST-7E, ST-8E and ST-9E contain all the electronics in the optical head.
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Page 12: Ccd Special Requirements
By cooling the CCD, the dark current and corresponding noise is reduced, and longer exposures are possible. In fact, for roughly every 5°C of additional cooling, the dark current in the CCD is reduced to half. The ST-7E and ST-8E Page 8... -
Page 13: Double Correlated Sampling Readout
CCD by the sky background typically limits the exposure time. The temperature regulation feature of the ST-7E, ST-8E and ST-9E also means that one dark frame can be used for similar exposures on several nights. At 0 °C the dark current in the ST-... -
Page 14: Flat Field Images
The pixel size of the detector in the ST-7E and ST-8E is 9 x 9 microns (1 micron = 0.001mm, 0.04 thousandths of an inch) and in the ST-9E it's 20 x 20 microns. -
Page 15: Guiding
35mm film is approximately 43mm, whereas the diagonal dimension of the ST-7E chip is approximately 8 mm. The relative CCD sizes for all of the SBIG cameras and their corresponding field of view in an 8" f/10 telescope are given below:... -
Page 16: Electronic Imaging
Once the data from the camera is received by the computer, the resulting image may be displayed on the screen at once. While Polaroid cameras also produce immediate results, serious astrophotography ordinarily requires hypersensitized or cooled film, a good quality camera, and good darkroom work to produce satisfying results. -
Page 17: Black And White Vs. Color
Section 2 - Introduction to CCD Cameras 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 gray, rather than color. -
Page 19: At The Telescope With A Ccd Camera
3.2. Attaching the Camera to the Telescope ST-7E, ST-8E and ST-9E cameras are similar in configuration. The CCD head attaches to the telescope by slipping it into the eyepiece holder. A fifteen foot cable runs from the head to the host computer's parallel port. -
Page 20: Establishing A Communications Link
Once the COM link has been established you may need to set the camera's setpoint temperature in the Camera Setup command. The ST-7E, ST-8E and ST-9E power up regulating to whatever temperature the CCD is at, which in this case will be the ambient temperature. - Page 21 Saturation Counts ~20,000 for ST-7E/8E ABG Cameras, ~40,000 for ST-7E/8E Non ABG cameras, ~65,000 for ST-9E 65,000 Table 3.2 - Saturation Values...
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Page 22: Finding And Centering The Object
Grab command. Because the ST-7E/ST-8E/ST-9E have regulated temperature control, you may prefer to take and save separate dark images, building up a library at different temperatures and exposure times, and reusing them on successive nights. -
Page 23: Advanced Capabilities
Section 3 - At the Telescope with a CCD Camera 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 supports the use of flat field frames to correct for vignetting and pixel to pixel variations, as well as a host of other image processing commands in the Utility menu. -
Page 24: Track And Accumulate
3.9.4. Autoguiding and Self Guiding The CCDOPS software allows the ST-7E, ST-8E and ST-9E cameras to be used as autoguiders and self-guiders through the commands in the Track menu. While these systems are not stand- alone like the ST-4, but require a host computer, they can accurately guide long duration astrophotographs and CCD images with equal accuracy. -
Page 25: Auto Grab
Section 3 - At the Telescope with a CCD Camera 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 position. - Page 26 Section 3 - At the Telescope with a CCD Camera 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 into a color image can give erroneous results.
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Page 27: Camera Hardware
4.3. Connecting to the Computer The ST-7E, ST-8E and ST-9E CCD Cameras are supplied with a 15 foot cable to connect the system to the host computer. The connection is between the camera and the Host Computer's parallel LPT port. The camera will operate properly with up to 50 feet of cable to the computer. -
Page 28: Using Mechanical Relays
Telescope port (see Appendix A for specific pin outs, etc.). The TIC-78 plugs into the 9-pin port on the ST-7E/8E/9E, and a standard phone cable, which we supply, connects the adapter to the telescope drive. Note: phone cables come in a few variations. We use the six-pin cable, and the pin order is reversed left to right relative to the connector from one end to the other. - Page 29 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 four buttons that have a "push to make"...
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Page 30: Modular Family Of Ccd Cameras
Modular Family of CCD Cameras With the introduction of the ST-6 CCD Camera in 1992 SBIG started a line of high quality, low noise, modular CCD cameras. The ST-7E, ST-8E and ST-9E are a second family of modular CCD cameras. - Page 31 "cover the telescope" and take dark frames remotely, without the user having to get up and physically cover the telescope. Electromechanical Shutter - Having the shutter in the ST-7E/8E/9E gives streak-free readout and allows taking dark frames without having to cover the telescope. While the minimum exposure is 0.11 seconds, repeatability and area uniformity are...
- Page 32 640 x 480 TC-237 320 x 200 ST-6 TC-241 375 x 242 ST-7E KAF0401E 765 x 510 ST-8E KAF1602E 1530 x 1020 9 x 9µ ST-9E KAF0261E 512 x 512 How these various specifications affect the average user is described in the following paragraphs: Number of Pixels - The number of pixels in the CCD affects the resolution of the final images.
- Page 33 ST-5C, ST-237 and ST-6 have it built into the CCDs and the Kodak CCDs used in the ST-7E and ST-8E have Antiblooming versions of the CCDs available. Blooming is a phenomenon that occurs when pixels fill up. As charge continues to be generated in a full pixel, it has to go somewhere.
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Page 34: Connecting The Older Model Cfw-6 Filter Wheel To The Camera
From these numbers you can deduce that the popular C8, an 8" f/10 telescope will nicely frame many popular objects with the ST-7E whereas a much shorter system (f/3, perhaps achieved with a focal reducer) will frame the same objects for the tracking CCD. Another point to bear in mind is that, except for planetary images, you'll rarely take images where the pixel size in seconds of arc is down near the seeing limit. -
Page 35: Battery Operation
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 22-132A, 12 volt DC to 115 volt AC Portable Power Inverter (140 watt) with good success. -
Page 37: Advanced Imaging Techniques
With the self guiding feature of the ST-7e/8E/9E one can take long integrations while the internal tracking CCD guides the telescope. -
Page 38: Taking A Good Flat Field
5.5. Building a Library of Dark Frames The ST-7e/8E/9E have regulated temperature control, and therefore it is possible to duplicate temperature and exposure conditions on successive nights. You can set the camera TE cooler temperature to a value comfortably within reach on your average night, and then take and save on disk a library of dark frames for later use. -
Page 39: Flat Fielding Track And Accumulate Images
Section 5 - Advanced Imaging Techniques 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. -
Page 40: Tracking Functions
5.8. Tracking Functions The CCDOPS software allows your ST-7E/8E/9E to be used as an autoguider or self guided imager. It does not function as a stand-alone autoguider like the ST-4, but instead requires using a PC to perform the function. These cameras have considerably better sensitivity than the ST-4. - Page 41 Section 5 - Advanced Imaging Techniques 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.
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Page 43: Accessories 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 compartment of the camera. This section tells you how to best use the Cooling Booster. -
Page 44: Tri-Color Imaging
Several third party vendors, including Celestron and Meade, make focal reducers for their telescopes that could be used with the ST-7E/8E/9E cameras. While most will work with the ST-7 some may have slight amounts of vignetting when used on the larger ST-8E/9E. -
Page 45: Sgs - Self-Guided Spectrograph
CCD. No more hunting around to place the object on the slit! With the SGS you can measure galactic redshifts, stellar classifications and determine nebular constituency. This is another example of the value of a self-guided camera like the ST-7E/8E/9E. 6.7. -
Page 46: Sbig Technical Support
Section 6 - Accessories for your CCD Camera 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. -
Page 47: Common Problems
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 is one of the most difficult areas in working with CCD cameras due to the lack of real time feedback when focusing. - Page 48 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 telescope's focus mechanism.
- Page 49 Section 7 - Common Problems 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. Page 45...
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Page 51: Glossary
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. - Page 52 ST-5C ST-237 ST-6 ST-7E/ST-8E 9 x 9 (unbinned) ST-9E 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 The TC241 CCD used in the ST-6 actually has 11.5 x 27 micron pixels.
- Page 53 Use the Parameters command in the Display menu to see the actual value for images acquired in other readout modes. The Non-ABG versions of the ST-7E and ST-8E have twice the full-well capacity of these values shown.
- Page 54 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.
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Page 55: Appendix A - Connector Ad Cables
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. - Page 56 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. Figure A1 - CCD Connector for TIC Mating Appendix A - Connector Pinouts Hand Controller Modular Phone Button Wire Color Special...
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Page 57: Appendix C - Maintenance
B.2. Regenerating the Desiccant This section describes the regeneration procedure for the desiccant used in the ST-7E/8E/9E. The desiccant absorbs moisture in the CCD chamber, lowering the dew point below the operating temperature of the cooled CCD, thus preventing the formation of frost. The desiccant is contained in a small cylindrical plug that screws into the chamber from the rear. -
Page 59: Appendix C - Capturing A Good Flat Field
Appendix C - Capturing a Good Flat Field 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 doughnuts), and stray light variations. - Page 61 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 operation, 15, 23...
- Page 62 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...
- Page 63 Index separations, 19 zoom, 18 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...