MODS Target Visualization and Guide Star Selection Tool
modsView is a Python program that uses DS9 to view and verify the target and guide star information in a MODS target acquisition (.acq) or imaging (.img) script. It displays a digitized sky survey image of the field in DS9 and overlays the outlines of the MODS focal plane (science field, AGw patrol field, and any slit apertures), as well as marking the guide star and overlaying NOMAD catalog stars labeled with their magnitudes.
While by default it uses digitized sky survey (DSS) images, it can also accept a user FITS image with a valid world coordinate system (WCS) in its header as the finder image.
modsView will test to make sure the guide star is inside the MODS AGw unit's guide patrol field. If any offset commands follow the telescope preset in the .acq or .img files, it also will test the post-offset position of the guide star to make sure it does not move out of the patrol field. The final MODS focal plane position drawn over the sky image will be at the offset position, allowing users to verify that they have the signs of blind offsets correct.
If a standard slit mask is used (long-slit or spectrophotometric slit), it will also overlay a view of the slit. The --mms option is used to allow display of multi-slit mask apertures given an MMS file.
The --shadow option will overlay a depiction of the region of the focal plane shadowed by the AGw guide pickoff probe, and show the effective fields-of-view of the guide camera and wavefront sensor cameras.
The --finder option creates a PNG-format finding chart suitable for use with Phase 2 program submission.
Other command-line options allow users to use different catalogs or image servers, add a grid, and make other minor changes.
An illustrated user's guide and downloads of the latest version are available online at www.astronomy.ohio-state.edu/MODS/ObsTools/modsView/, but will migrate off that platform in the future.
modsView is written in Python 3 and has been tested on Linux and macOS. Python 3 is required, and the programs have been used primarily with Python v3.7 and up.
The latest version requires the most recent versions of ds9 and xpa, since there were significant internal changes in 2021.
modsView requires the following packages:
With Python 2 sunsetting on 2022 Jan 1, we now require Python 3 for all versions of modsView moving forwrd. The current version has been verified to run on Python 3 (v3.9.13, anaconda distro), using the latest releases of pyds9. We no longer support modsView under Python 2.
You have two options: Personal or Public installation
For a personal installation, you have two ways to install the files to use:
- Keep the modsView Python programs in place, and put the modsView directory in your default execution path.
- Copy the executable Python programs into your ~/bin/ or ~/programs/ directory where you put executables in your default execution path.
For a public installation, e.g., on a central disk to share one copy of the package among many users, we suggest logging in as root and unpacking the tarball in your usual place for public add-on programs, e.g., /usr/local/, and then installing the executables in, e.g., /usr/local/bin/.
If you used modsView in your research work, we ask that you follow emerging software citation principles being adopted by the astronomical community to ensure the proper citation of software in scientific publications.
modsView was developed for the MODS1 and MODS2 instruments at the Large Binocular Telescope Observatory, which were built with major support provided by grants from the U.S. National Science Foundation's Division of Astronomical Sciences Advanced Technologies and Instrumentation (AST-9987045), the NSF/NOAO TSIP Program, and matching funds provided by the Ohio State University Office of Research and the Ohio Board of Regents. Additional support for modsView was provided by NSF Grant AST-1108693.
We've tested this on macOS 10.14 and later, and macOS 11 and 12. It does require having ds9 v8.2 or later and xpa v2.1.20 or later. It appears to work better with the X11 versions of ds9 instead of Aqua, and confirm that BigSur ARM64 X11 works fine with macOS Monterey (on Intel and M1).
These notes are chronological from most recent to oldest releases. Older copies of modsView are available below, but we strongly recommend that you only download the latest version. This is the version that is installed at LBT.
This is the current operational version of modsView to support MODS1+MODS2 Binocular operations
- Version 2.2.1 (2022 Nov 11) - Python 3 version
- Now only supporting Python 3, and made changes to XPA commands needed to match syntax changes in ds9 and XPA in 2021.
- Version 2.1.7 (2019 Nov 24) - AGw patrol field update
- Updated the coordinates of the AGw patrol field to better match the current least-common denominator patrol field for MODS1 and MODS2.
- Version 2.1.6 (2018 Sep 05) - Python 3 fixes
- Fixed bug in Python 3 compatibility (raw_input instead of input). Caught by Johnny Greco, tested on iMac running MacOS HighSierra and anaconda python 3.6.5
- Verison 2.1.4 (2018 May 22) - SNS Masks
- Support for experimental SNS masks, will not impact normal users
- Version 2.1.3 (2016 Dec 04) - Cosmetic Patch
- This is a patch for version 2.1 that addresses a minor cosmetic issue in one print statement that elicited comment from some users.
- Version 2.1.2 (2016 Nov 15) - min/maxmag Patch
- This is a patch for version 2.1 that addresses a problem whereby users could not change the minimum (faint) and maximum (bright) catalog star magnitudes for display with --minmag/--minmax.
- Version 2.1.1 (2016 Oct 15) - ds9 Patch
- This is a patch for version 2.1 that addresses a problem encountered by users with an older version of pyds9. While we urge people to update to the latest version of pyds9, this patch will bridge the gap.
- Version 2.1 (2016 Oct 12) - MAJOR UPDATE
- Version 2 is a major update to support MODS1 and MODS2 binocular operation starting with LBT Semester 2016B when the MODS1 WFS pickoff optic was updated so that it is the same as in MOD2. As a result, there is now no practical distinction between MODS1 and MODS2 for modsView, but, you should check all pre-2016B MODS1 scripts with modsView to verify that your guide star selections are still valid with the reconfigured MODS1 guider (MODS2 scripts will not have this problem).
These are notes on Version 1 which was pre-binocular MODS operation.
- Version 2.0 (2015 Nov 20) - Initial MODS2 support
- Version 2.0 added support for MODS2, and correctly drew the MODS1 and MODS2 guide-probe positions for the different WFS pickoff optics then in MODS1 and MODS2. After we updated the MODS1 WFS pickoff optics to be the same as MODS2 in October 2016, this version was retired, and must not be used.
- Version 1.6 (2015 Jan 22) - new features
- Added additional interaction to the --find feature for guide star selection. It now requests you confirm the new guide star choice or allow you to repeat the selection or abort. This makes modsView more convenient for initial guide star selection, and at the telescope. Added some additional script syntax checking - for example it now requires that OBJNAME and GUINAME have an argument (at least "None") otherwise it aborts. A blank OBJNAME/GUINAME will cause an acq script to fail at the telescope.
- NOTE: Version 1.6 is the last release of modsView before
Version 2.0. It only supports MODS1. Use Version 2 to pick
guide stars for MODS1 and MODS2.
- Version 1.4.3 (2014 Feb 23) - bug patch
- Bug found in plotting the guide patrol field that would allow selection of stars that are outside the AGw stage Y-axis limits after an offset of ~13mm to put the guide star into the WFS hotspot. Also found a place where the dimensions of the guide patrol field had been entered twice and different. This bug patch Addresses issues encountered at the telescope during engineering tests that selected guide stars as far as possible away from the optical axis on UTC 2014 Feb 23.
- Version 1.4.2 (2013 Apr 11) - bug patch
- Allows for the case of MMS files with no + signs on declinations. While this technically not permitted in well-formatted MMS files, it can still happen, especially in MMS files that might be altered by hand. We now test for and allow this case. Also fixed a hitherto undetected bug in the rendering of the guide probe shadow under RA/Dec offsets.
- Version 1.4.1 (2013 Mar 19) - bug patch
- Fixed a bug in the offsetting logic that would only have been apparent in certain RADEC offset combinations at high declinations.
- Version 1.3.4 (2013 Jan 7) - incremental bug patch
- Fixed a bug in --minmag/--maxmag whereby it was possible to give modsView nonsensical magnitude limits (bright limit fainter than the faint limit). This condition is now trapped at startup and the crash-point it causes in findStar() patched.
- Version 1.3 (2012 Dec 19) - feature update and bug patch
- Fixed bugs in instrument view after offsets. Added the ability to display tilted MOS slitlets with --mms and restored the --rotate feature. A patch added Dec 19 addresses a minor problem with python 2.7 with the --find option.
- Version 1.2 (2012 Dec 03) - major release
- Added numerous (mostly transparent) enhancements to execution. Added --find to print a candidate list of guide stars to select from, and the NOMAD1 catalog is now the default star catalog. The AGWFILT value in the acq script is used to select B magnitudes to display on the finder if AGWFILT=B_Bessel. The summary report has been expanded to give more details, including star catalog data (R and B mags) for the guide star if available. Also fixed a number of bugs, cleaned up some ds9 setup, and updated the webpages.
- Version 0.6.6 (2012 Jun 10) - incremental bug patch
- Fixes a bug in the display of the guide probe shadow when a blind RADEC offset is requested in the acquisition script.
- Version 0.6 (2012 May 21)
- Introduces MMS file overlay and user FITS image support, customization of the DS9 window appearance, and quick fixes for some ugly bugs that snuck into v0.5. This is the last beta testing release before v1.0 (the full public version) is launched.
- Version 0.5 (2012 May 20)
- Second beta release. Adds the --shadow option to overlay the outline of the nominal guide probe shadow and OBJNAME labeling.
- Version 0.4 (2012 May 4)
- First beta release of modsView.
modsView was based on an earlier, nasty bit of Perl code that made a DS9 regions file you could read into ds9 by hand (or via xpaset from the shell). It was developed mostly for planning purposes early in the MODS project, but not developed further until we started MODS on-sky operations. An intermediate version named luciView was developed at OSU for checking LUCI scripts, as syntax and guide-star errors in LUCI scripts was a major problem early on in OSU/RC queue operations.
The need for a similar capability for MODS led to reviving modsView and rewriting it in Python, building off our experiences with the modsDisp program deployed for a quasi-realtime display of raw MODS images at the telescope, and our experiences (good and bad) developing the lbtView program for selecting guide stars for MODS and other LBT instruments using the ESO skycat package. The success with modsView led us to halt all development of lbtView, which was phased out completely in 2013.