Abridged version of Pegasus Release 9402

31 January 1995

This is a summary of the changes made to the Pegasus software in the latest release. All modifications are in effect as of the above date. See the "News" button in the Pegasus sessions for the most current information.

Highlights of PEGASUS 9402 Release

The priority of 9402 was to improve the PEGASUS code which impacted session-wide development and to provide better user feedback. Call it infrastructure development if you like. As such, individual data acquisition sessions will need further reviewing to take advantage of the rich set of features the 9402 release has provided.

Groundwork has also been layed for the soon to be released multiple-screen workstations. These workstations will allow the users to better make use of screen real estate.

o Exposure sequencing modified

In the previous versions of sequence control software, most errors reported by the various sub-system processes were ignored. The end result was often an incorrect exposure if a piece of hardware failed to be commanded properly.

9402 corrects this such that any pre-exposure failure will halt the exposure sequencing process. What is deemed a fatal pre-exposure error is determined by the Project Scientist and application programmer.

Any sub-system failures after the exposure completes do not impact the sequencer.

o User feedback improvements

In general, the user feedback has improved in many ways. First of all, the feedback window now includes color-encoded messages: red for fatal and yellow for warnings.

Secondly, much of the feedback window information has been edited out and sent to the system log files instead. The end result is a much "quieter" feedback window.

Real-time range checking has been incorporated into the Xforms. This means less time lost to illegal values entered by the user. Also, what were considered illegal characters before, such as the abbreviation for arc-seconds ("), are now valid to be entered.

And finally, the other really noticable improvement is in the session startup: fewer debugging messages and more positive indications of the session's startup health.

o IQE improvements

IQE has been modified to better equip it to evaluate all of our detectors' data. A new IQE algorithm was chosen over the IRAF algorithm because it provides a FWHM for the major and minor axis of elliptical images, as well as an orientation angle. The new IQE is not prone to large position dependant errors for single pixel FWHM, offers a more robust background determination and it's FWHM determination should be more resistant to noise. The focus and autofocus routines will benefit from IQE's enhancements too.

o New detector status windows

This includes feedback for the detector temperature and useful information about the detector in use.

o Correction of cassegrain bonnette central mirror actions for calibrations

After yet another go-around of discussions, the central mirror is now being left in its current position unless the latest activity specified by the user requires it to be moved into a new position. The previous revisions had the mirror repositioning automatically for each individual calibration exposure or for each sequence of exposures.

o OCS upgrades

Many enhancements were done to the Observatory Communications System to make it more robust and easier to interact with programmatically.

o Code cleanup

A positive move towards embracing the ANSI version of 'C' has been taken. As a result, many of those transient, hard to reproduce, bugs have been flushed out and subsequently eliminated.

o New sessions

New observing sessions were established for the detector group to allow them to work in Waimea completely autonomous from the summit operations.

o FITS card DATEOBS changed

This card is now DATE-OBS and is in the format of dd/mm/yy to be compliant with FITS standards.

Partial List of Outstanding Problems

) Stop, Hold, Abort may exhibit problems for CCDs and Redeye.

) Zooming SAOimage too many times causes a core dump, ie, crash. (Sorry, its not our software to fix in-house, but that may soon change.)

) Video focus on GenIII detectors (loral3, redeye, bear) is not yet available; use iterations of object.

) IQE does not work with images which have been "combined" or "preprocessed". However, Grapher does and it may be able to provide the information you seek.

) Several buttons on the preprocessing forms have a strange "feature" -- the left-half seems to be insensitive to button pressing. If in doubt, click on the right-half of the button!

) Grapher X-axis tic marks need improvement.