Release Notes for Science Data Archive
User Interface (Version 1.8.1)
Release Date: Monday, 17 March 2003
Version 1.8.1 of the Science Data
Archive (SDA) user
interface (UI) implements several enhancements made since the
releases of Version 1.6.2 on 20 November 2002 and Version 1.8 on 12
March 2003. These enhancements are described in Changes since v1.6.2 and Changes since v1.8.
Version 1.8.1 includes many new tools and functions that were
originally designated for the upcoming release of v2.0. Because
these new tools significantly enhance the navigation of the UI and access to the
data, we chose to release them now rather than wait for all the
goals for v2.0 to be completed. Described below are the hardware
and software requirements for v1.8.1, the basic functionality of
v1.8.1, summaries of changes since v1.6.2 and v1.8, the known bugs
and limitations of v1.8.1, and the planned improvements for the
v2.x series of UI releases.
There are no specific hardware requirements for operating the UI. Any computer that
accommodates efficient WWW browsing will be sufficient for basic UI functionality.
However, computers should have sufficient memory and processing
speed to display and manipulate drizzled WFC images, which can be
as large as 250 MB.
The UI is a
WWW-based interface to the SDA
database and image storage media (RAID). The UI has been designed with
bindings) standards, so it will perform well with any WWW
browser that fully supports these standards. The recommended
browsers for the UI are:
Netscape 4.7x (for any platform) and Internet Explorer 5.x
(for Windows and Unix) do not properly execute the UI and are therefore not
supported by the ACS archive group.
Proper use of the UI requires the following
browser options be set:
- Permission to open new windows must be granted
These options are default settings on most browsers. For Mozilla
and Netscape, they are changed via the "Edit Preferences" menu
option --> "Advanced" category --> "Scripts and Windows"
Finally, a FITS image
viewer must be installed to properly display FITS images through the UI. Such viewers
To enable your browser to spawn the FITS viewer, edit your browser
preferences to include a MIME type of "image/x-fits" for extension
"fits " and the correct path to the executable for the FITS viewer.
The UI has two
- Search and retrieval of
CALACS and APSIS image
- Search and analysis of objects listed in APSIS catalogs
Whereas both functions were performed via a common query form in
v1.0, the search and retrieval of images are now performed via a
dynamically generated data inventory page. Searches for detected
objects are still performed through the query form. This form has a
tabbed format, meaning that the basic steps of a query (defining
search criteria, selecting output fields, and viewing results) are
accessed through a tabbed menu.
The SDA stores selected images
CALACS and APSIS. The
CALACS images are produced by on-the-fly calibration through MAST. Only the calibrated FLT
and CRJ files, which are the input products of APSIS, are stored in the SDA. All other
CALACS files must be retrieved through MAST. The APSIS image products that are stored in
the SDA are:
- Drizzled and combined images (science, wieight, RMS, and
context) for each filter (from module combDither)
- Combined filter images (science and weight) for object
detection (from module combFilter)
- Segmentation images identifying detected objects (from module
detectionCatalog via SExtractor)
- Images of background around detected objects (from module filterCatalog via SExtractor)
CALACS and APSIS images can be
downloaded through the UI's data inventory and/or
displayed with standard FITS image viewers spawned by the
WWW browser. The detection images generated by APSIS can be viewed as color PNG files
through set summary pages linked to the data inventory. The
ancestors and descendents of each archived image can be traced,
thereby providing the user a pedigree of every archived APSIS run.
Objects in each GTO image are identified and characterized
photometrically, astrometrically, morphologically, and
cosmologically by APSIS. The
object catalogs generated by APSIS
(detection, filter, photometry, and BPZ) are transformed into searchable
database tables. Object queries are formed by constraining selected
parameters from each of these catalogs.
Version 1.8.1 offers several tools for inspecting and analyzing
the results of object queries:
- Summary pages containing basic information and cut-out (or
"postage-stamp") images of each object
- Collective displays of cut-out images of many detected
- Sorting output columns in ascending or descending order
- Downloadable tables in ASCII, CSV, TSV, HTML, and XML formats
The following enhancements and bug fixes have been implemented
- The default format for Object Maps and color cutout
(or "postage stamp") images has been changed from PNG to JPEG. The
JPEG images load 2-3 times faster than the PNG images. An option to
download Object Maps in PNG format is provided.
- The Object Map control panel has been augmented with controls
for setting the dimensions of the field of view, overlaying Kron
apertures, and inverting the color palette.
- Extinction-corrected magnitudes have been added to the Object
- The "clear" filter-wheel positions have been deleted from the
annotation of the cutout-array pages to reduce clutter. Compound
filter labels now appear only when both ACS filter-wheel positions
contain actual optical elements.
- The HST program numbers listed in the archive Set
Summaries are now linked to their respective Program
The following enhancements and bug fixes have been implemented
- Extinction-corrected magnitudes (and errors) have been added to
the Photometry Catalog. These new parameters (MAGNITUDE_CORR and
MAGNITUDE_CORR_ERR) have been produced since the release of APSIS v2.0. The uncorrected
magnitudes remain available in the SDA under the parameters
MAGNITUDE and MAGNITUDE_ERR.
- The Object Map now features a control panel that allows the
user to pan across three-color APSIS images with pixel bin settings of 1
to 8. SExtractor apertures can be overlayed at any bin setting.
Object Maps can now be downloaded in PNG and PDF formats. (PDF
format is currenly available only for maps with aperture
- Previously viewed images are now cached by the client browser,
which reduces significantly the time to redisplay the images and
relieves the load of the image server.
- The footprints of large objects in the Object Maps have been
converted from circles to polygons to minimize interference with
- An external database query tool has been added to the Object
Summaries, allowing searches for objects up to 10 arcmin from
detected objects in the SIMBAD, NED, SDSS, MAST, and GSC2
- Arrays of cutout ("postage stamp") images for objects selected
from query results now return the cutouts from all filter images,
rather than just those constrained by the input and output
parameters of the query. These multiband cutout images are now
ordered by increasing wavelength.
- Detection-image cutouts may now be downloaded in FITS format
from the Object Summaries and cutout array pages.
- Infrequent misalignment of the green channel in the color
Object Maps and image cutouts has been fixed.
- The vintages of archived
CALACS and APSIS images are
now represented by their creation dates, rather than their
SDA-ingestion dates, in the Data Inventory and Program
- The names of the CRJ and FLT files contained in the Program
Summaries and Set Summaries now appear exactly as produced by
CALACS. The "SCI_1" extensions, which were vestiges of an
aborted plan to archive
CALACS files in simple FITS format, have been removed.
- Input files that appeared multiple times in the Set Summaries
are now listed once.
- Set Summaries for obsolete APSIS products now display links to the
most current APSIS products for
- The page number of the displayed page of query results is now
reinitialized between queries.
- The printable results page now shows the position of the
displayed records within the entire results set.
- Missing column headings in downloaded results tables have been
restored. Extraneous columns in the downloaded results tables have
- A bug in the PHP array_reduce function occasionally causes a
failure of the Program Summary page. This bug has been reported to
the developers of PHP.
- The region box within the Object Map control panel cannot be
dragged by the pointer in the Internet Explorer 6.0 browser. The
box can be repositioned by pointing and clicking within the control
panel or by entering the x and y coordinates of the center of the
Because v1.8.1 is a preview of the larger v2.0 release, it lacks
some important functionality requested by the GTO team at the
Summer 2002 meeting in Wyoming. Limitations of this release
- Color constraints on catalog queries have not yet been
- Magnitude constraints on catalog queries are limited to single
filters or are uniformly applied to all filters.
- Graphical representation of catalog parameters has not yet been
CALACS header keywords have not yet been implemented as object
- Multiple image file downloads have not yet been
Planned improvements for the v2.x series of UI releases include,
but are not limited to:
Inquiries may be directed to:
- Object queries constrained by multiple magnitudes and
- Object queries constrained by
CALACS header keywords
- Two-parameter plots and histograms of catalog parameters
- Color-magnitude and color-color plots of calibrated
- Multiple image file downloads
Last modified 02 April 2003 14:02:04