"Astrometrica" User Information

• New features in "Astrometrica" Version 3.20 to 3.25.
• Download "Astrometrica" Version 3.25.
• New astrometric catalogs and "Astrometrica".
• Tools for download
• Problems and Bug Reports:
  • Problems with SVGA graphics mode and mouse operations.

• Access to new astrometric catalogs (USNO-A1.0, USNO-SA1.0 and ESA-Tycho).
  
• Expanded file interface will also read HiSys CCD Images.
  
• Ephemeris will optionally show variations (useful for recovering objects with uncertain orbits.)
  
• Improved reference star selection: The CCD images will always be shown at the same size (40% of the width of the screen), regardless of the original size. Furthermore, the CCD image is now also drawn on the Recall Reference Stars command.
  
• Improved brightness and contrast control while blinking images.
  

• Support for the new FITS date format (according to IAU resolution A4).
  
• Automatic generation of a list of opposition dates for minor planets.
  
• Configure 'Remeasure' command with or without Background measurement.
  

• Display of background sky brightness (mag/square arcsec).
  
• Improved FITS support.
  

• Backup ASTROMET.INI as ASTRMINI.OLD at startup.
  
• Further improved FITS support.
  
• Minor bug fixes.
  

• Support of the USNO ACT, USNO-SA2.0 and USNO-A2.0 catalogues.
  
• Display of the reference star number in the results screen.
  
• SVGA 1280 x 1024 mode. (Note:This is expermiental only. On my system, for example, displaying and measuring images works fine, but blinking images does not work. I am not yet sure wheter this is a fault of the graphics card in my PC, or of the SVGA driver used by "Astrometrica".)

• Occasionally incorrect Residuals using the Tycho catalogue corrected.
• Optionally flip images horizontally and/or vertically on loading.

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• USNO-A 2.0 and USNO-SA 2.0
  The USNO-A catalog, the largest star catalog ever compiled, includes astrometric and photometric data on nearly half a billion stars, from the brightest naked eye stars down to magnitude 23. The mean reference stars density of this catalog, which consists of 11 CD-ROMs, is about 12000 stars per square degree, but, of course, is lower at high galactic latitudes, and much higher in regions within the milky way.

  The USNO-SA has data on about 55 million objects, extracted from the USNO-A catalog to produce a spatially uniform net of faint (mainly 16mag to 19mag) reference stars with a density of about 1300 objects per square degree. The astrometric positions of both the USNO-A and the USNO-SA are said to be accurate to about 0.25", and the new version 2.0 of both catalogues have been reduced to ACT reference frame, so they are probably the most accurate high-desnsity star catalogues available today. The single CD-ROM USNO-SA 2.0 catlog is available for free from the Astrometry Department of the U.S. Naval Observatory.

  Important Note: While the USNO-SA catalog is generally available at no cost, but individuals who need USNO-A must provide a sufficient and succinct scientific justification for why their need is not satisfied by USNO-SA when contacting the Astrometry Department of the U.S. Naval Observatory!

• ESA Tycho
  The Tycho catalog, shipped together with the Hipparcos catalog and other data from the ESA Hipparcos mission on six CD-ROMs, contains information on positions, proper motions and magnitudes of about one million stars down to magnitude 11. The precision of this catalog is outstanding: The positions of stars is accurate to 0.007" down to 9mag, and to 0.025" for fainter stars, while the magnitudes are good to 0.012mag and 0.06mag, respectively. However, due to the short duration of the Hipparcos mission, proper motions are rather inaccuarte, giving increasingly less precise positions at future epochs (but note the ACT catalogue below). Furthermore, with "only" one million stars, the mean density is no more than about 25 stars per square degree. Benefit for CCD-observers will therefore be rather limited.

  Note:"Astrometrica" can not access the Hipparcos/Tycho data on the Celestia 2000 CD-ROM (no information on the file format is available).

• USNO ACT
  The ACT combines the precise positions from the ESO Tycho and the Astrographic Catalogue (AC). The large time span between the two catalogues (mean epochs 1991 and 1907, respectively) yields proper motions about one order of magnitude better than in the original Tycho catalogue. Like Tycho, it includes only about one million stars down to magnitude 11, but due to it's high precision, this catalogue is the choice for the most demanding astrometric obervations, lile last minute astrometry for stellar occultations by minor planets.

  According to Sean E. Urban, the U.S. Naval Observatory has run out of ACT CD-ROMs. The complete catalog is, however, available for download in the U.S.A., Europe, and Japan. So one can eventually write his orher own ACT CD-ROM.

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• ElemConv (35 kB): A tool by the author of "Astrometrica to convert orbital elements from the MPC Computer Service or the MPC orbit database (available here) to "Astrometrica's" ELM file format.
• Ast2Elm (50 kB): A tool supplied by John W. Rock (U.K.) to convert orbital elements from the Lowell observatory minor planet database (available here) to "Astrometrica's" ELM file format.
• GSCConv (86 kB): A tool supplied by Paulo R. Holvorcem (Brazil) that converts the output from the GSC 1.2 online query to ASCII files read by "Astrometrica". For further information on GSC 1.2, see section 6.11 of the "Astrometrica" README file.
• Pic32 (16 kB): A tool supplied by Luca Boschini (Italy) for adding information to the HiSys file header. See the notes on HiSys images in section 6.06 of the "Astrometrica" README file for further information.

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If you encounter any problems using the graphics display of "Astrometrica", check the list below for possible reasons and solutions:

• List of supported graphics chipsets:
  The following SVGA graphics chipsets are detected and supported by the SVGA interface used by "Astrometrica":
  VESA, Weitek, Chips & Technologies, Paradise, Compaq, Video7, Genoa, Everex, Cirrus 54XX, Cirrus 64XX, Trident 8800/8900, ATI, Ahead A & B, NCR, S3, Avance Logic 2101, MXIC 68000, Acumos, Realtek, Primus 2000, Oak, UMC, HMC and Tseng ET3000/ET4000/ET3000W32
  As noted above, a VESA compatible graphics card is highly recommended.

• VESA TSR:
  If you are using a VESA TSR to get SVGA support, make sure that you are using the very latest version available. Some VESA TSRs originally shipped with graphics cards have some bugs and do not work correctly. If no VESA TSR is available for your graphics card, you may try SciTech's Display Doctor, a universal VESA interface for many graphics cards. An evaluation copy of "Display Doctor" is available from here.

• Disable SVGA Operation:
  In case the "Astrometrica" graphics mode is not working properly, you may try to start the program using the /NoSVGA command line option. This will disable SVGA operations, and should work on any VGA compatible graphics card. However, the software neither can use the high resolution 800x600 mode, nor blink more than two images in this mode.

• Mouse Operation:
  If your mouse does not work at 800x600, you may try the HGXMOUSE tool shipped with "Astrometrica", which adds Super VGA support to an existing mouse driver. Please refer to the HGXMOUSE documentation for details. Note that HGXMOUSE is shareware, and if you make use of it, you must pay the shareware fee to the author of that tool!
  Alternatively, you may update your mouse driver to support high resolution graphics modes. For example, Logitech offers a mouse driver that supports VESA operations for download from their ftp site (make sure to download the DOS / Windows 3.1 driver for use with "Astrometrica").
  Windows 95 users should also note that a DOS mouse driver is loaded (usually done by DOSSTART.BAT) to support mouse operations in DOS mode.

• Memory Manager:
  Operating a memory manager, like EMM386 or QEMM, may cause conflicts with SVGA modes. Make sure to follow the vendor's instructions to excluse certain RAM address regions used by the graphics card from being used by the memory manager or network software. Also, disable the "Stealth" option when using QEMM.

• Monitor Synch Frequency:
  Some monitors have limited synch capabilities, and may not be able to synch correctly when using the SVGA 800x600 mode. If you get a garbled display at 800x600, make sure your monitor is capable of this resolution and synch frequency.

• Running "Astrometrica" from Windows:
  Although not officially supported by the developer of the SVGA interface used by "Astrometrica", it does work on most systems. Windows 95 users can also start the computer in MS-DOS mode when running "Astrometrica" from Win95 causes any problems, but make sure that a DOS mouse driver is loaded (usually done by DOSSTART.BAT).
  Furthermore, note that changing the graphics settings for Windows has no effect on DOS programs. You must use the the 'Options - Settings' command from within "Astrometrica" to change the graphics mode it uses.

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