Operating Manual for the Model ST-5C Advanced CCD Camera Santa Barbara Instrument Group Santa Barbara Instrument Group 1482 East Valley Road · Suite 33 PO Box 50437 Santa Barbara, CA 93150 PHN (805) 969-1851 (FAX) (805) 969-4069 Email: sbig@sbig.com Home page: www.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 and used in accordance with the instructions, may cause harmful interference to radio communications. However, there is no guarantee that interference will not occur in a particular installation. If this equipment does cause harmful interference to radio or television reception, which can be determined by turning the equipment off and on, the user is encouraged to try to correct the interference by one or more of the following measures: · · · · Reorient or relocate the receiving antenna. Increase the separation between the receiver and the equipment. Connect the equipment into an outlet on a circuit different from that to which the receiver is connected. Consult the dealer or an experienced radio/TV technician for help. Changes or modifications not expressly approved by the party responsible for compliance could void the user's authority to operate the equipment. Also note that user must use shielded interface cables in order to maintain product within FCC compliance. ST-5C Manual Fifth Printing May 1998 Table of Contents 1. Introduction to CCD Cameras....................................................................................................3 1.1. How CCDs Work.......................................................................................................................3 1.2. CCDs Applied to Astronomical Imaging..................................................................................4 1.2.1. Cooling..................................................................................................................4 1.2.2. Dark Frames..........................................................................................................5 1.3. The Various CCD Parameters and How they Affect Imaging..................................................5 1.3.1. Pixel Size...............................................................................................................5 1.3.2. Full Well Capacity ................................................................................................5 1.3.3. Dark Current.........................................................................................................6 1.3.4. Read Noise............................................................................................................6 1.3.5. Frame Transfer......................................................................................................6 1.3.6. Antiblooming Protection ......................................................................................7 1.3.7. A/D Bits and Digitization Rate ............................................................................7 1.3.8. Binning..................................................................................................................8 1.3.9. Spectral Response .................................................................................................8 1.4. Camera Hardware Architecture................................................................................................9 2. The First Day with the Camera................................................................................................. 11 2.1. Setting up the System.............................................................................................................. 11 2.1.1 Installing the CCDOPS Software......................................................................... 11 2.1.2. Getting Acquainted with CCDOPS Software..................................................... 12 2.1.3. Connecting the Camera to the Computer .......................................................... 14 2.1.4. Establishing a Communications Link with the Camera..................................... 15 2.1.5. Operating your Camera with CCDOPS - a Daytime Orientation ..................... 15 2.2. The First Night with the Camera ............................................................................................ 17 2.2.1. Focusing the Camera .......................................................................................... 18 2.2.2. Finding and Centering the Object ...................................................................... 19 2.2.3. Taking an Image ................................................................................................. 19 2.3. Further Foray's into CCDOPS................................................................................................ 19 3. Advanced Imaging Techniques................................................................................................ 21 3.1. Taking a Good Flat Field ......................................................................................................... 21 3.2. Track and Accumulate ............................................................................................................ 21 3.3. Color Imaging.......................................................................................................................... 21 3.4. Autoguiding ............................................................................................................................ 22 3.5. Field Operation........................................................................................................................ 22 4. Glossary ..................................................................................................................................... 23 5. Hints and Tips........................................................................................................................... 27 5.1 Question and Answer............................................................................................................... 27 5.2. CCDOPS Use Tips ................................................................................................................... 29 5.3. Hints and Tips for Laptop Users............................................................................................. 29 5.4. Telescope Tips ......................................................................................................................... 30 A. Appendix A - Specifications.................................................................................................... 33 A.1 DC Power Jack......................................................................................................................... 33 A.1 Communications Port ............................................................................................................. 33 A.1 Telescope Port ......................................................................................................................... 34 i B. Appendix B - Maintenance ...................................................................................................... 35 B.1. Replacing the Fuse .................................................................................................................. 35 B.2. Disassembling/Reassembling the Optical Head.................................................................... 35 B.3. Cleaning the Optical Windows............................................................................................... 35 B.4. Replacing the Desiccant .......................................................................................................... 36 ii Introduction Congratulations and thank you for buying the SBIG ST-5C Advanced CCD Camera. This camera offers incredible performance in a small package for a moderate cost. Using the camera will expand your astronomical experience by allowing you to easily take images like the ones you've seen in books and magazines, but never seen when peeking through the eyepiece. CCD cameras offer convenience, high sensitivity (a typical deep-sky image is several minutes), and advanced image processing techniques that film just can't match. While CCDs will probably never replace film in its large format, CCDs offer ease of use and allow a wide range of scientific measurements. Their use has established a whole new field of Astronomy. Some of the features you'll discover about your camera include: · · · · · · · · · · Based on the Texas Instrument TC255 CCD with 320 x 240 pixels that are 10 microns square. Double Correlated Sampling readout with 16 Bit A/D for the lowest possible noise. Convenient and fast parallel interface offers full frame download times under 4 seconds. Thermoelectric cooling gives sky background limited performance. Integral Shutter Wheel that can be replaced with a Color Filter Wheel for Tricolor imaging. Telescope port for use as an Autoguider. Advanced CCDOPS software for data acquisition, display and processing. Track and Accumulate 1for hassle-free long duration exposures. 12 VDC operation allows use in field with a car battery. Standard T-Thread allows use with a variety of telescope adapters including the standard 1.25 inch nosepiece and eyepiece projection units. This manual is organized for two types of use. Some sections have been designed to be read through from the start while you're learning about the camera and the software whereas other sections are to be used for reference. Briefly the manual consists of the following sections: · Section 1 describes CCD cameras and how they work. While it is the first section of the manual, it is a bit technical, and some users may wish to skip ahead to the second section then come back to this section once they have had a little hand's on experience. Section 2 tells you how to install the camera and CCDOPS camera software and takes you step by step through the process of taking your first images. Even if you have experience with other cameras you should browse through this section and read any sections that are new to you. Also for further training and detailed technical information regarding the CCDOPS software for the ST-5C please refer to the separate CCDOPS manual. Section 3 presents some more detailed information about how you use the camera for some slightly more advanced tasks. The discussion of even more advanced topics is continued in Appendix D. Once you have become familiar with the basic operations of the camera you will want to read these sections. Sections 4 and 5 provide a Glossary of common CCD imaging terms, a Question and Answer section on the most common questions you'll have and a section of · · · 1 Track and Accumulate covered by SBIG US Patent 5,365,269. Page 1 Introduction useful hints and tips for using the camera. Again, this is a good section to read once you have had a little time with the camera. · Finally, the Appendices provide a wealth of technical information about the camera. Page 2 Section 1 - Introduction to CCD Cameras 1. Introduction to CCD Cameras The CCD (charge coupled device) is very good at the most difficult astronomical imaging problem: imaging small, faint objects. For such scenes, long film exposures are typically required. The CCD based system has several advantages over film: greater speed, quantitative accuracy, ability to increase contrast and subtract sky background with a few keystrokes, the ability to co-add multiple images without tedious dark room operations, wider spectral range, and instant examination of the images at the telescope for quality. Film has the advantages of a much larger format, one-step color, and independence of the wall plug (the ST-5C camera can be battery operated in conjunction with a laptop computer, though). After some use, you will find that film is best for producing sensational large area color pictures, and the CCD is best for planets, small faint objects, and general scientific work such as variable star monitoring and position determination. It is for this reason that we designed the camera to support both efforts, as an imaging camera and as an auto-guider to aid astrophotography. 1.1. How CCDs Work The CCD is a solid-state imaging detector that is quite commonly used in video tape cameras and is starting to find acceptance in still frame cameras. It has been used for Astronomical Imaging for over twenty years. The CCD is arranged as a rectangular array of imaging elements called pixels. An image is formed by reading the intensity of these pixels. The basic function of the CCD detector is to convert an incoming photon ...