Users are advised to use caution as these data sets have not yet completed peer review and the subsequent lien resolution. See the Current Status section below for issues specific to each data set.

Please notifiy the PDS Rings Node if you find any errors or have recommendations to improve these data sets.

Overview

The PDS Rings Node is producing four new multivolume Voyager ISS data sets - one for each of the outer planets. The volume IDs are VGISS_xxxx as opposed to the originally distributed volumes with IDs VG_xxxx. There is a one-to-one correspondence between the calibrated volumes and in their counterpart volumes in the originally distributed, raw only, data set (e.g., VGISS_0004 covers exactly the same FDS range as VG_0004).

These new data contain data from four processing levels:

• Raw Image: uncompressed version of the original file
• Cleaned Image: spikes and reseau marks removed
• Calibrated Image: dark current subtraction and calibration model applied
• Geomed Image: geometrically corrected image
The processing levels are progressive (e.g., geometrically corrected images have also been cleaned and calibrated). For information on processing levels, please see a Voyager calibrated ISS TUTORIAL.TXT file found in the DOCUMENT directory of each volume.

The data directories in the original volumes were sorted by target. In response to recommendations from the peer review panel for the Saturn data set, the data directories in the calibrated volumes will be sorted by image number. This extensive reorganization is implemented during the updating between preliminary and peer review versions. In the case of the Saturn data set the reorganization was implemented post peer review.

Each data set is placed on line as quickly as possible - before the full set of processing steps is complete. The currentl level of a given volume can be determined from the volume name:

• VGISS_xxxx_prelim - a "preliminary" data set. Contains all of the images in at least the raw and cleaned formats; may also contain calibrated and geometrically corrected images. The individual image metadata will be available in the VICAR header for each image, but PDS label files some additional documentation will not be present.
• VGISS_xxxx_peer_review - a data set ready for, or in, peer review. Will contain raw, cleaned, calibrated and geometrically corrected images. Each image retains its VICAR header and is accompanied by a PDS label file.
• VGISS_xxxx_lien_resolution - a data set which has passed peer review with liens that are currently being resolved.
• VGISS_xxxx - the final, fully archived version of a data set.

Users are strongly encouraged to review the TUTORIAL.TXT file found in the DOCUMENT directory of each volume. This file provides a comprehensive guide to the data in these data sets.

Current Status of each Data Set

• Preliminary version, only contains uncompressed, raw images and limited documentation. The data directories are sorted by target (original structure) not by image number.
• ".tar.gz" bundles of the raw volumes may be placed on line by the beginning of November, 2008.
• Reorganized, calibrated volumes will be placed on line as they are produced, perhaps as early as the end of calendar year 2008.

• Two versions on line: peer review and the initial release of the lien-resolved data set. Lien resolution is still in progress and (generally minor) changes may appear without notice.
• The data set has been entirely reorganized and data directories are sorted by image number, not target
• Because of processing issues identified during peer review, we have concerns about the validity of some of the calibrated images in the peer review version of this data set. Every image has been re-calibrated in the lien resolution version. Users should avoid using the calibrated images found in the peer review version of any Saturn data volume.
• ".tar.gz" bundles of the lien resolution volumes will be placed on line near mid-October, 2008.

• Preliminary version, contains all four processing levels. The data directories are sorted by target not by image number.
• Because of processing issues identified in the Saturn data set, we have concerns about the validity of some of the calibrated images in this data set. The data set will be re-calibrated, and the data directories will be reorganized by image number prior to release for peer review.
• Re-calibrated volumes may be available as early as the beginning of November, 2008. ".tar.gz" bundles of the peer review volumes will be placed on line by the beginning of December, 2008.

• Preliminary version, only contains uncompressed, raw images and limited documentation. The data directories are sorted by target (original structure) not by image number.
• ".tar.gz" bundles of the raw volumes may be placed on line by the beginning of November, 2008.
• Reorganized, calibrated volumes will be placed on line as they are produced, perhaps as early as the end of calendar year 2008.

Identifying the Data You want

The one-to-one correspondence between the calibrated volumes and the original raw image volumes, means that one can use the existing Rings Node Search options. These use the original raw image catelogs. Once you identify the desired raw images or raw image volume, then merely adjust the filename or volume ID to obtain images from the calibrated data set (e.g., VGISS_0004 covers exactly the same FDS range as VG_0004).

Naming conventions

For details on the volume structure and file naming conventions, please review a Voyager calibrated ISS AAREADME.TXT file (especially section 4). This file (with minor header variations) appears in the root directory of every volume. NOTE: AAREADME files in preliminary volumes maybe incomplete.

Getting the Data You want

The individual volumes, even compressed for download, are very large; consequently we have divided each volume into separate bundles for downloading. Each bundle is in .tar.gz format. For information on opening files of this type, click here.

Each bundle contains all documentation files from the full volume and all the data files at one of the four processing levels: raw, cleaned, calibrated, or geometrically corrected. The first two types are typically ~ 500MB, the last two are ~1-2 Gbytes.

The table below provides direct access to the calibrated volumes and to available bundled subsets of the calibrated volumes. Not all will be available in bundles immediately; this page will be updated as more become available. Generally we do not prepare bundled versions until the volume is ready for peer review. However, we will respond as quickly as possible to user requests for bundles of preliminary volumes.

• Clicking on the VOLUME_ID will take you to the root directory of the volume.
• To download an entire single processing level subset of a given volume, right click in the appropriate 'bundle' column.
• Browse links go to directories of 200 X 200 pixel GIF images.
  • Browse images for VG_0001 & VG_0002 are on VG_0003.
  • Browse images for VG_0004 are on VG_0005.
  • Browse images for VG_0006 & VG_0007 are on VG_0008.
  • Browse images for VG_0009, VG_0010 & VG_0011 are on VG_0012.
• Clicking on INDEX.TAB will take you to the index file for that volume. The index file is a twenty one column, ASCII table listing each image on the volume along with some information extracted from that image's label file. Descriptions of the columns can be found in the INDEX.LBL file in the INDEX subdirectory on each volume.

* Volume VGISS_0038 also contains a selection of images in the FDS range 42286.05 to 43568.49 that were missing from earlier volumes