Previous Changes and bugs

Release 4.0.0

Changes in this release include:

• The version of Skycat that GAIA is based on has been updated to version 3.0-1. Major changes to the GAIA infrastructure.
• When merging FITS headers from the primary data unit into those of an extensions the INHERIT keyword is now checked.
• Inline compressed images (RICE) are now extracted more efficiently using built-in methods, rather than an external filter. The primary headers are now merged into such images as needed.
• Reading FITS catalogues is now also handled using built-in methods. This should be more efficient.
• FITS catalogues can now have 64 bit integer columns ('K' type).
• Compressed NDFs can now be opened directly in the cube toolbox.
• Very small images now fill the zoom window. Previously small images did not show correctly.
• The rotatable box graphics item can now be used as a catalogue symbol.
• The spectrum can now be re-extracted by pressing a simple button, as well as by clicking on the image.
• The data range used to display the extracted spectrum can now be defined explicitly.
• The spectral cube window will now retain some settings between sessions.
• FITS spectra now have the extraction meta-data added to their headers.
• The default on-line catalogue list has been updated. Fixes a problem with NED CADC access and includes some new CADC catalogues and the JCMT archive.
• The "gaiadisp" command has been extended to accept a percentile cut as a command-line option.
• The SMURF extension data are now ignored in their dimensions do not match the cube. This probably means the cube has had addition processing that makes the extension data invalid (or at least misleading).
• Bug fixes:
  • Re-opening modified cubes now works (via File->Re-open and gaiadisp).
  • The spectral offsets from the centre of the observation of cube now preserve the sense of the direction by including a sign.
  • A bug when writing an extracted spectrum to NDF and FITS files has been corrected. Previously the coordinates were incorrect by a single channel.
  • Data values are now only reported when moving over part of the image. Previously reports continued for an additional pixel to the bottom and left.
  • When the first pixel has a NaN or blank value and has less than 10 pixels the lower value is now correctly set, rather than being left at the bad pixel value.
  • The various bounds for extracting spectra etc. should now work correctly when the lower bound is greater than the upper bound.
  • Increased the output length of a TST catalogue line to 4096 characters from 1024.
  • The rebin cube tools now correctly use "mean" as the combination method. Previously "sum" was used until either "mean" or "sum" was explicitly selected.
  • FITS images that contain NaN values should now contour correctly.
  • A bug that caused image region circles to be drawn at the wrong scale has been fixed.
  • A bug extracting a TSYS value when cubes have greater image dimensions than expected has been fixed.

Release 3.3-7

This version of GAIA is part of the Puana release. This is an update with many usability changes and minor bug fixes:

• New "Rebin" controls have been added to the cube toolbox. These allow the current cube to be rebinned and displayed.
• New "Filter" controls have been added to the cube toolbox. These allow the current cube to be smoothed, image plane by image plane, using a box or gaussian filter.
• A new "Go" menu has been added to the cube toolbox. This is similar to the main window menu, but only displays possible cubes, arranges for them to be efficiently loaded and attempts to preserve the current spectral extraction limits.
• Spectra extracted from ACSIS cubes now contain various useful information, such as various RA and Decs, the exposure time of spectrum and the system temperature. These can be displayed by the SPLAT-VO application synopsis feature, when such a spectrum is sent to it.
• The centroid maximum search box size and shift are now start up options that can be defined either on the command-line, or using the "File->Startup options..." dialog (this makes the change permanent)
• The variance and quality components of a cube can now be displayed.
• The FITS headers of a cube can now be inspected.
• Spectra can now be sent to other PLASTIC-enabled applications using the Interop menu in the spectral plot window. Only SPLAT-VO supports this at present.
• Extracted spectra can now be saved to NDF and FITS files. The "Send to SPLAT" options now send NDF spectra, previously they sent a text file.
• Extracted spectra may now contain additional meta-data about the extraction position. This will be displayed in the SPLAT-VO synopsis.
• An animated GIF of a range of image slices can now be created.
• The grid overlay and celestial coordinate system toolboxes now support Horizon (AZEL) coordinates.
• The celestial coordinates toolbox now supports the use of the sky reference position as an origin (for offset coordinates) or local pole.
• Images of size 1x1 should now be accepted and handled as other images. Previously such small images had a special status which meant that no image was displayed.
• Images that have one dimension of size 1 are now correctly autoranged and oriented (previously these were always drawn horizontally).
• Cubes with trivial first and second dimensions are now loaded into the cube toolbox when -check_for_cubes is set. Previously these were considered as special form of images.
• The measurement band now measures to the image edge, not middle of edge pixels.
• A bug when extracting a spectrum over a restricted range meant that the coordinates of an NDF or FITS were incorrect (by an offset). This has been fixed.
• Timeseries cubes can now be switched between different time scales.
• The default cube axis is now selected to be the spectral one. Previously the third axis was always chosen.
• The "send to SPLAT" option in the cube toolbox now sends the absolute name of the spectrum to be displayed. This means SPLAT may be started from another directory.
• The "send to SPLAT" options in the cube toolbox have been extended to allow the spectrum to be compared to any existing ones (the old behaviour) and to replace any spectra already plotted.
• Ranges used to extract spectra and control other operations are now preserved, except when the size of the underlying cube changes. This makes it easier to extract similar spectra and re-use baseline regions.
• Channel maps now have a marker drawn to display the same position in each tile. The average spectral coordinate is also displayed and the channel map is given the same coordinate system as the used by the cube.
• The coordinate system of a channel map is now matched to that of the current cube, so that any displayed coordinates are in the correct context.
• When a cube is collapsed the result image is now in the same coordinates as the current ones in use by the toolbox. This gives the correct units for any integrated intensity measurements.
• The distance ruler now measures to the middle of the final pixel to the top and right of the display. Previously this stopped one pixel further in.
• FITS headers are now shown out to 80 characters. Previously they were truncated at 79.
• The precession facility of the positions toolbox should now correctly transform the current list of coordinates, rather than a single position.
• The cube spectral extraction now handles dependent axes (like RA and Dec), differently so that more extractions along one of these axes will succeed.
• The XY profile toolbox can now be activated using control-e. This also avoids the prompt dialog reminding you to draw a rectangle.
• The handling of broken WCS components in NDFs should now result in the display of an image/cube, without a WCS rather than an unrelated error report about a missing data component.
• The direction compass is now always a fixed size, not one that depends on the image scale. Should now always be visible.
• The initial order of baseline subtraction is now shown with the correct value (previously this was incorrect until the value was modified).
• A bug causing a double free core dump when saving modified world coordinate systems for NDF data has been fixed.
• A fatal bug when reading FITS headers from multiple NDFs in a container has been fixed.
• The behaviour of the spectral plot window can now be changed so that it no longer remains above the main window. To enable this option either start GAIA with -transient_spectralplot 1, or set this option in the "File->Startup options..." dialog (this makes the change permanent).

Release 3.2

The most significant changes in this release are in cube handling. The toolbox is now much faster at image slicing and handles FITS cubes as well as NDF cubes. It also features an all new, built-in, real-time interactive spectral extraction display, which features point and region extraction. It also has new controls for creating channel map images and selecting ranges for baseline subtraction. On 64bit platforms cubes greater than 2Gb can be handled.

As part of these cube handling updates, all the image analysis toolboxes now also work on cube slices. Spectral analysis features are provided by communication with SPLAT-VO, which works outside of GAIA.

GAIA can now also interoperate with some PLASTIC enabled applications.

Other major changes in this release are that the version of Skycat has been updated (after a long pause of five years) to 2.4.7, along with an update to using Tcl/Tk 8.4.11.

Highlights of the change to Skycat 2.4.7 include a new feature for the display of MEFs, and groups of NDFs, as a single image.

There are also many minor changes in this release of GAIA:

• GAIA can now display in-line compressed images (such as RICE from WFCAM). These are converted into temporary files on the fly and can be used with all other tasks within GAIA.
• The ESP toolbox now reports the mean count along the isophote and plots intensity profiles.
• A rarely seen problem with foreign-file conversion deleting the input files has been fixed.
• The object detection toolbox has been updated to work with SExtractor version 2.4.3. This includes Petrosian magnitudes and some windowed parameters.
• The Second U.S. Naval Observatory CCD Astrograph Catalogue (UCAC2) has been added to the default list. Existing users will be prompted to remove the file $HOME/.skycat/skycat.cfg and re-start GAIA to make this available.
• The 2MASS catalogue query now includes a minimum radius. This change will be included with the UCAC2 update.
• The GAIAIMAGEPICK_DIR environment variable now selects default directory for Pick-Image toolbox log file.
• The image slice now has a option to display the Y axis using a log scale.
• The cube slice display toolbox now has options for continuously looping (including "rock-and-roll").
• The "Show all coordinates" toolbox now displays coordinates from systems with more than 2 axes.

Finally in this release GAIA has undergone major changes in the way that it is built and distributed (it is now available in the Starlink CVS repository and uses an autotools based build system). During this change IRAF support has been dropped, although the IRAF support files are still available in the CVS repository.

Release 2.8-0

A major release of GAIA incorporating a new NDF cube handling facility. GAIA will now detect 3D input data (ideally in NDF format) and display slices along one of the extra dimensions. This may be animated.

You can also create a new image that is a combination of images between a range of indices. The tool also shows the world coordinates along the extra dimensions. All displayed and created images can be processed like any other image, so you can perform photometry, region statistics etc.

The following more minor issues have also been fixed.

• GAIA has been relinked against AST to fix a problem when the presence of multiple possible astrometries in FITS headers causes the image scale to be incorrectly estimated.
• The astrometry tables now offer a button to project X,Y to RA,DEC to complement the reset projection of RA,DEC to X,Y.
• Contouring toolbox bug fixed. If you entered an incorrect NDF name for the second image, the error was never recovered and GAIA had to be restarted.
• Printing the "whole image" now works when repeated without exiting GAIA.
• Incompatibilities in the WCS components of NDFs are now ignored (older versions of AST cannot read newer encodings).
• A problem with coordinate readout coupling when using more than one interactive slice or XY profile is being used.
• A error reading the CRPIX values in the blink/compare toolbox has been fixed.

Release 2.7-4

This is a major release of GAIA incorporating two new automated astrometry toolboxes, a major re-write of the blink comparison toolbox and many changes and fixes.

GAIA now offers two new toolboxes based on the Starlink AUTOASTROM program. These make it possible to provide a minimum of positional information (image centre and scale) and then fit an astrometric solution. They also make it possible, for the first time, to fit optical distortions. The new toolboxes are available at:

        Image-Analysis->Astrometry Calibration->Automatic position matching
    

One is for simple use and the other for advanced use.

The blink comparison toolbox has been substantially upgraded in this release. New features are options to alignment to NDF origins or FITS CRPIX values. This gives much better behaviour when comparing images of different dimensions. Better performance (less flickering artifacts). The ability to drag images and enter image coordinate offsets. All images can now be viewed together or one-by-one as before. Images should now always scroll and the "Refresh" button has been removed.

Other changes in this release:

• Spitzer/SIRTF FITS headers, including the optical distortion, are now handled.
• The NDF component chooser now allows the variance component to be displayed as expected.
• A new default percentage autocut option has been added.
• Shared memory segments under Solaris should now be better behaved.
• The handling of byte images is changed so FITS BITPIX=8 are correctly interpreted as unsigned byte, not signed byte. This change mostly effects the XY profile and contouring toolboxes.
• An attempt to clear old WCS information from images before saving is now made.
• The "gaiadisp" command has been enhanced to load a list of images into GAIA.
• An experimental tabbed interface has been produced to make it easier to view FITS MEF files. To try this out use the command:

            $GAIA_DIR/tabbedgaia
          

• Long thin or tall images (2 pixels or more) now display a readout of positions.
• The "$GAIA_DIR/pix2wcs" and "$GAIA_DIR/wcs2pix" scripts should be working again.
• The "$GAIA_DIR/displaycat" command now creates fully functional catalogue windows (previous these did not include any GAIA specific changes).
• The "-catalog" command-line option now accepts a list of catalogues to display immediately.
• The polarimetry toolbox now correctly processes selection expressions when column names are short forms of other names (i.e. when P and PI, DP and DPI etc. are used). Previously an attempt to interpret $PI as $P would be made and subsequently fail.
• Making name queries using the RedHat 9 build of GAIA failed completely, sometimes causing a core dump from a child process. This problem has now been resolved.
• The interpretation of FITS -CAR projections is now a configuration option. Previously this was fixed at assuming that all Cartesian projections are simple linear mappings (this remains the default), ignoring the possibility of spherical rotations. Refer to the CarLin attribute of the AST (SUN/211) library for more about this change.
• Various changes to grid overlays have been implemented. This now supports AST 3.2 super-script and sub-script, font and colour changes within a string. Fonts drawn on the overlay grid can now be scaled with image. Better matching of postscript font size to displayed size has also been implemented. A long term memory leak has been cured (only seen when drawing overlays).
• A new configuration option "always_merge" controls if the primary header of any FITS files are merged with those of extension being viewed to create a full set of headers for creating a world coordinate system. By default this merging no longer occurs when the primary HDU contains a non dummy image.
• Region statistics now also include values for the NDF variance component.

Release 2.6-12

New to this release:

• A number of new catalogues and image servers are now available. When GAIA starts for the first time it will ask for permission to update your configuration, unless you have a very customised ~/.skycat/skycat.cfg file, you should just say yes. Some highlights are 2MASS, USNO B1.0 and GSC II.
• A new configuration option "-extended_precision" has been added. This makes GAIA work at approximately milli-arcsecond resolution. This option can be switched on using the new "File"->"Startup options" window.
• The pixel table now highlights the maximum and minimum values and the orientation of the Y-axis has been flipped so that the sense of the values is the same as that in the image.
• The command-line options of GAIA can now be configured using the new "File"->"Startup options" window. The set of options selected are used whenever GAIA starts up (this removes the tedious need to either specify these on the command-line, or add them to your X resources).
• A new configuration option "-show_hdu_chooser" has been added. By default when you open a FITS or HDS file that contains more than one image the HDU chooser appears so that you can select between the images. On some occasions (mainly when running GAIA under remote control) this behaviour is unwanted and the chooser should remain inactive. This option can be controlled using the new "File"->"Startup options" window.
• When North and East are interchanged the "Show all coordinates" displayed the wrong coordinates in the left and right columns, and incorrectly formatted RA as DD:MM:SS and Dec as HH:MM:SS. These problems are now fixed.
• The direction arrows shown in the pan window could be displayed at the wrong size, again when North and East were interchanged. This problem is now fixed.
• Fixed shape ellipses in the aperture photometry toolbox were actually created using an inverted zoom factor correction (so either shrank or expanded in the wrong sense). This now works correctly.

Problems and bugs with this release

The NDF chooser doesn't offer the ability to view a variance component (this option stays greyed out). The only work around (until the next release) is to use the "-component variance" option on the command-line.

The two utility scripts "pix2wcs" and "wcs2pix" are broken. Use these versions instead: pix2wcs, wcs2pix. They will need execute permission.

Secondary coordinate systems in FITS headers will not be understood (and of more concern, will invalidate the whole set of coordinate systems) if they make use of CDELT1/2[A-Z] keywords. This will be fixed in the next release of GAIA. Contact me if this is an issue for you and you cannot remove the secondary coordinate system signature.

There is a serious problem with the name resolver when running the RedHat 9 build of GAIA that causes it to silently crash and never return. The only work around is to change to the RedHat 7.3 build version. A copy of this for the Summer 2003 release may still be found at:

      ftp://ftp.starlink.ac.uk/pub/users-ftp/pwd/gaia/rh73-summer2003/
    

When this is removed you will need to upgrade.

Release - 2.5

This release (which was only available from the Starlink Software Store) includes two new toolboxes, various significant improvements and some bug fixes.

The first new toolbox provides the long awaited ability to identify and record image positions interactively. It also allows the import of coordinates stored in text files (of various formats) and their transformation to the celestial coordinate system of the displayed image (for instance this allows you to read FK4 positions and correctly position these over an image with an FK5 astrometry). Each position can also be labelled and cumulative image properties (including seeing) are calculated.

The second toolbox displays the mean X and Y profiles of a rectangular region. If the rectangle is moved the profiles will update in real time. This is useful for detecting background trends and binning up linear features.

A further major change is the addition of support for displaying multiple extension FITS files (MEFs). It is now possible to examine images and catalogues stored in these files. A similar feature has also been introduced for NDFs that are stored in the same container file.

Additional minor changes are:

• The SExtractor toolbox has been updated to work with the latest version of EXTRACTOR and SExtractor (see {SUN226}).
• The SExtractor toolbox no longer requires that you press <Return> to update any text fields (this seemed to cause a lot of confusion).
• A new command-line option -quiet_exit has been introduced. This can make GAIA ask before exiting the main window. The default remains to not ask.
• The file selection dialog now attempts to preserve the last filter pattern.
• GAIA should now work correctly with X servers whose default visual doesn't match the requested visual.
• A bug in the aperture photometry toolbox that caused some detached sky regions to randomly move has been fixed.
• Catalogue windows now have the option to interpret X and Y coordinates as NDF pixel_coordinates (useful for plotting POLPACK results).
• The precision shown for the RA and DEC fields in the main window has been restored to show 0.1 arcsec resolution.

Release - 2.6-6

Release 2.6 includes a new toolbox and various enhancements.

The new toolbox displays maps of polarization vectors as produced by the Starlink POLPACK package (SUN223). It also provides manipulation facilities for selecting map sub-sets and allows the map to be re-binned.

Additional minor changes are:

• You can now choose the secondary coordinate system that GAIA displays in the `RA' and `Dec' coordinate readouts. This is useful when your images have more than one coordinate system that you'd like to view (by default NDFs have `PIXEL' and `AXIS', as well as others such as celestial coordinates, FITS files may have similar arrangements in the future). As a consequence of these changes the `PIXEL' system is now removed from the celestial coordinates and grid overlay toolboxes.
• SuperCOSMOS surveys are now available. To access these you need to remove the file $HOME/.skycat/skycat.cfg, if it exists, and then look in the ``Browse Catalog Directories...'' dialog under the ``Data-Servers'' menu for the sub-list ``SuperCOSMOS catalogues''.
• FITS file with more than one period in their names can now be displayed by GAIA. However, some toolboxes are effectively disabled by this as it breaks the {NDF} library naming conventions for foreign data formats.
• The on-line help system has been completely re-engineered. This is now based on a hypertext system with text search facilities. Other improvements are the inclusion of figures and a more unified presentation.
• BITPIX -64 FITS files (i.e. double precision) can now be displayed, but note that some external applications that are used by GAIA cannot properly process this format (e.g. AUTOPHOTOM and EXTRACTOR which are used by the photometry and object detection toolboxes will truncate to single precision floating point).
• The contour toolbox now has new options to use a single colour and/or width for all lines.
• The contour toolbox now has a new option for adding customised colours (RGB/CMY/HSV or standard X11) to its drop-down lists.
• You can now get a copy of the colour ramp, annotated with levels, for inclusion in diagrams.
• Importing plain text files of values is now available as an option for normal catalogue windows (previously this option just imported files into the positions toolbox). This allows files that have space, comma, semi-colon and tab separated fields to be read, as well as files with fixed-width columns.
• The conflict with the CURSA setup for the SKYCAT_CONFIG environment variable is now resolved by ignoring SKYCAT_CONFIG. This was causing GAIA to lock up when used behind a web proxy that had not been configured.
• The UKSTU plate library has been removed from the default catalogue list. This facility is no longer available.
• The irritating failed to register the shmem:// driver warning message should now be silent. This warning was harmless.
• The pan window should now work with very thin images (1 pixel wide).
• The "autocut" mechanism has been modified to not use the DATAMIN and DATAMAX keywords (which are often not the minimum and maximum data values in an image) and a bug effecting its operation when scaled images were abutted to the top-edge of the display has been fixed.

  There have been many complaints that autocuts do not work as expected, one reason for this is that the cuts are determined by using a sub-sample of the part of the image data that you can see, rather than the whole image. One effect of this is that percentile cuts will correctly produce different high and low levels depending on what part of an image you're looking at.

• All image access (that is NDFs and FITS files) is now performed using file mapping. A consequence of this is that GAIA will now display images up to 2Gb in size on machines with more modest physical memory allocations (a 256Mb Linux PC will display such images comfortably, but note that any analysis operations may need much more memory). If you attempt this you will still require a system whose virtual memory size is bigger than 2Gb.
• An error in the RMS fitting estimate for the astrometric toolboxes has been corrected. Previous RMS values were all underestimates by a factor 1/sqrt(n).
• The rendering of ellipses drawn as graphics overlays (such as those used to show object detections) has been improved, especially at low resolutions.

Problems and Bugs in these releases

Some non-transient pop-up windows currently grab the focus during their creation (for instance the NDF chooser). This problem will be fixed in the next release of GAIA.

FITS astrometries stored in NDFs could result in a report to the terminal about missing FITS keywords followed by a failure to load the image (with a dialog message about "missing data component"), this problem will also be fixed in the next release. To work around this you need to either repair the FITS headers or remove them altogether. The KAPPA commands (see {SUN95}) "FITSEDIT" and "FITSMOD" can be used to edit FITS values. The command "ERASE" can be used to remove them completely, e.g:

   % kappa
   % fitsmod my_ndf CRVAL2 write 1 "Dummy" !
    

Would set a value for the keyword "CRVAL2", and:

   % kappa
   % erase my_ndf.more.fits ok
    

Would remove the FITS headers completely.

DSS FITS astrometries. Solutions in the south do not work as the signed part is not picked up. To work around this change the value of the PLTDECSN keyword from '-       ' to '-'.

There have been some reports about an error dialog saying that a "table doesn't contain any columns" is being seen when loading images into GAIA. So far this has been caused by the previously displayed images history file: ${HOME}/.skycat/history being corrupted. If this happens to you just delete the file. I would like to know if this problem is widespread so let me know (a copy of the corrupted file would also be useful).

Release 2.6-9

This release just includes a few updates

• New X_PIXEL and Y_PIXEL parameters have been added to object detection toolbox (these report pixel coordinates, i.e. include any origin information).
• Non-transient pop-up windows that grabbed the focus during their creation (for instance the NDF chooser) have had their behaviour modified to not grab the focus.
• While processing FITS astrometries stored in NDFs a report to the terminal about missing FITS keywords followed by a failure to load the image (with a dialog message about "missing data component") could occur. This problem is now fixed.
• The astrometry fitting toolboxes (using reference positions) have been upgraded to accept RA and Dec values with space separations. Note that in general you should use colons as the separators.
• The image print window has been modified to swap the page width and length values when changing between landscape and portrait formats. This should make better use of the full page by default.

Problems and bugs

When North and East are interchanged the "Show all coordinates" toolbox displays the wrong coordinates in the left and right columns, and incorrectly formats RA as DD:MM:SS and Dec as HH:MM:SS.

The direction arrows shown in the pan window can be displayed at the wrong size, again when North and East are interchanged.

Fixed shape ellipses in the aperture photometry toolbox are currently created using an inverted zoom factor correction (so either shrink or expand in the wrong sense).

All these problems will be fixed in the next release of GAIA. If you need a pre-release then contact me.

Questions or comments to: p.w.draper@durham.ac.uk.