Patrick Moore s Practical Astronomy Series

Transcription

1 Patrick Moore s Practical Astronomy Series For other titles published in this series, go to

2 So You Want a Meade LX Telescope! How to Select and Use the LX200 and Other High-End Models Lawrence Harris

3 Lawrence Harris Stowupland UK ISSN ISBN e-isbn DOI / Springer New York Dordrecht Heidelberg London Library of Congress Control Number: Springer Science+Business Media, LLC 2010 All rights reserved. This work may not be translated or copied in whole or in part without the written permission of the publisher (Springer Science+Business Media, LLC, 233 Spring Street, New York, NY 10013, USA), except for brief excerpts in connection with reviews or scholarly analysis. Use in connection with any form of information storage and retrieval, electronic adaptation, computer software, or by similar or dissimilar methodology now known or hereafter developed is forbidden. The use in this publication of trade names, trademarks, service marks, and similar terms, even if they are not identified as such, is not to be taken as an expression of opinion as to whether or not they are subject to proprietary rights. Printed on acid-free paper Springer is part of Springer Science+Business Media (

4 Acknowledgments Books take time to be written. During that time, various people are called upon to help resolve the puzzles and queries that arise. Many people helped me arrive at the end of this project, so I want to acknowledge that help here. I am indebted to Richard (Dick) Seymour, Andrew Johansen, Mike Weasner, and Jason Ware for their sterling work, reading drafts of the components of Chap. 2 and offering several useful suggestions based on their own expertise of the LX scope series. Their help during the writing of the PEC section was unsurpassed. Rather than merely using my own images I posted a request for contributions and was delighted with the quality of images supplied to me. I regret that only a few could be selected because of space limitations. My thanks to all who responded. My grateful thanks to Ray Gralak, the author of PEMPro who kindly agreed to check the draft of the PEC software section for errors. Terry Platt helpfully checked Chap. 9 and provided some interesting pictures. Dr. R.A. Greiner and Dr. Clay are in a class of their own when it comes to expertise of the mechanics and operations of the LX200/LX400 series of telescopes. Both are credited elsewhere, but must be thanked here for their valuable contributions. John Watson and Maury Solomon of Springer have been instrumental in helping me to get this book suitably prepared for publication. Their patience with my endless queries has lasted a long time and I am very grateful. My better half, Marion has read this book as a nonastronomer to check that I have not been throwing astronomical acronyms around too excessively. Apart from that, never have we drunk so much tea and coffee each day as during the final run toward chapter submission. The book would not have happened had she not been more than patient with me. Any errors that get through, however, are mine. v

5 Contents 1 Introduction... 1 Computers and Astronomy... 1 Look Before You Leap!... 1 Advancing from Binoculars... 2 Telescope Types... 3 Small Refractors... 3 Refractor Accessories... 4 Reflectors... 6 Moving On Up... 6 Telescope Suppliers Web Sites... 7 Enter the Goto Handbox... 8 Star and Polar Alignment... 8 Mid-range Scopes... 9 Wedges for Imaging The Importance of a Balancing System Equatorial Head Autoguiding Accessories for Imaging Your Ideal Scope Time/Date Latitude/Longitude Entry Focusing Collimation Polar Alignment Drive Accuracy Periodic Error Correction Telescope Mounts The Final Telescope Upgrade! vii

6 viii Contents 2 Meade LX200GPS/LX400 Series Telescopes Getting Started What s in a Name? Meade LX200GPS and LX What You Get in the Box LX200GPS and LX400 Connector Panels The Equatorial Wedge Field Derotator Power Considerations Sun Warning! GPS Receivers First Visual Observing Sessions: Finder Adjustment, Focusing, Collimation Focusing Hartmann or Bahtinov Mask Changing Speed LX400 (and LX200GPS with Care) Handbox Removal Collimation LX400 Collimation AutoStar Suite Operations AutoStar Suite Updates Connection to AutoStar Suite Telescope Control Menu Tree Updating ASU and Firmware Upgrading Firmware Use the Latest Firmware Restoring a Corrupted Handbox Free User Software Telescope Alignment Goto Synchronization Training the Drive Smart Mount Testing SMT Caution, Static! Daytime Planetary Viewing Yahoo Telescope Groups Commercial Servicing Facilities Summary Accessories, Great and Small Replacement Screws An Equatorial Wedge? Astro-Engineering UK Telescope House Milburn Wedge... 50

7 Contents ix Balance Rails and Weights Dew Heaters Dew Shields Autoguiding Telescopes Focal Reducers Barlow (Extender) Units CCD Cameras: Main and Guide Filters Software Adaptive Optics Units Observatories Dehumidifiers Hartmann Mask Bahtinov Mask Balancing and Polar Alignment Equatorial Wedges Setting Up Your Scope Getting an Approximate Polar Alignment Balancing in Declination Declination Axis Balance Vertical Balance Horizontal Balance Right Ascension Axis Balance Precise Polar Alignment Visual and CCD Monitoring of Polar Alignment Adjustments Demonstrating East to West, North to South Misalignment Errors Manual Adjustment of the Polar Axis Azimuth Adjustment Reiterative Adjustments Adjusting the Elevation Software Aid in Polar Alignment Next Stage Essential Software for Basic Operations Supplied Control Software The ASCOM Initiative Initial Connection to your Hardware Using MaxIm DL Operations with MaxIm DL Camera Control Configuring the Scope: Taking Control Guide Camera Focusing MaxIm DL Telescope Header Settings Synchronizing the Telescope with the Sky... 91

8 x Contents Solving an Image Camera Orientation Synchronization Field Calibration Image Processing Camera Cooling Flat Images Bias Images Dark Images Try Some Gotos Software Adjustment of Periodic Error and Polar Alignment Measuring Periodic Error What Is PE and Why Do You Need to Fix It? Essential Previous Checks Out-of-the-Box Images How Long Can You Expose? Measuring and Correcting Your PE PEC Settings The Details Consequences of the PEC Table Adjustment Periodic Error Management by Software Finding a Suitable Star Using the Simulated Handbox Handbox Settings Collecting Raw Data: A Caution Analyzing Your PE Data Uploading the New PE Correction Curve Check the Result Refining Your Curve What a Good PEC Means Adjusting the Sidereal Drive Polar Alignment: The Importance of Being Accurate Software Polar Alignment Further References Autoguiding Principles of Autoguiding Backlash Autoguiding Error Magnitudes Getting Good Guide Stars: Choose Your Guide Scope Carefully Flexure Bright Guide Star Guide Camera Exposure

9 Contents xi Gusts and Mirror Flop Correction Commands MaxIm DL Guide Settings The Importance of the Aggressiveness Setting The Maximum Move Setting The Minimum Move Setting DEC Compensation Setting LX200GPS and LX400 Series PEC A Mini Review Guide Log Graphs Sample Guide Settings Configuring the Autoguider Focusing and Centering the Autoguider Guide Star Dark Calibration Calibration of Autoguider Autoguiding Test Mind Where You Walk! What Follows is a Cautionary Tale! References Using Advanced Software A Day (Night?) in the Life Astrometrica Asteroid, Comet, and Supernova Detection CCD-Inspector PoleAlignMax/FocusMax AstroArt MaxIm DL ACP Observatory Control Software Suite Multitasking! Summary CCDCommander MPO Connections CCDAutoPilot PHD Guiding Additional Software GPS Control SkyTools TheSky (v6) CCD-Navigator CCD-Stack Adaptive Optics Limitations of Guide Scope Use Active and Adaptive Optics: The Principles

10 xii Contents One Guide Camera Professional Application Amateur Equivalents Starlight Xpress Active Optics Unit (SX AO) Telescope Focal Ratio CCD Guide Camera Assembling the Unit Cable Configuration Software Connection Focusing the SX AO Guide Camera Dark Frame Calibration of the Autoguider Full Calibration of the Adaptive Optics Unit Bump Calibration Calibrate SX AO First Test Results and Summary Messier Ready for M Background SX AO Settings Conclusions A Guide to Weather Satellites A Brief History of Weather Satellites The Cold War Agreement Weather Satellite Orbits What Do the Images Show? Visible Light, Infrared, and Water Vapor Images Polar Orbiting Weather Satellites NOAA Polar Orbiters Receiving and Decoding NOAA Weather Satellite Images Hardware and Software Websites with Current a.p.t. Imagery Geostationary Weather Satellites: Image Formats GEONETCast: A Worldwide System Animating Geostationary Weather Satellite Images Some Features Seen in Satellite Imagery Some LX200 and LX400 Projects Lunar Impact Studies Searching for Extrasolar Planets Comet Imaging Astrometry Deep Sky Pictures Andrey Batchvarov George Hall

11 Contents xiii Hilary Jones Bill Norby Richard Robinson Stuart Thompson Charles Trump Merope and Its Nebulosity Twilight Flats Processing Author s Note Index

12 About the Author Lawrence Harris retired from his job as a British government space scientist following nearly two decades at the leading edge of space research. For almost 20 years, Harris has been a columnist writing about weather satellites and space research in some of the top astronomical publications. He has also contributed extensively to astronomical society magazines. Harris is the proud owner of several Meade LX telescopes, including the top end LX400 telescope. xv