Home of MagAO and MagAO-X.
After our pre-ship review, we had a few things to fix – the only difficult one was a misbehaving actuator in the ASM. These have all been dealt with, and after a final review by the director we today received permission to ship the Magellan AO system to Chile.
LCO here we come!
Some packing pictures courtesy of Carmelo Arcidiacono:
The Magellan AO VisAO camera includes a novel system for performing “frame selection”, which is the technique of using only periods of good seeing and/or AO correction in the final science image. Traditional “lucky imaging” does this by reading short exposures and selecting in post processing. In our system, we use measurements of Strehl ratio in real time and open and close the shutter based on those measurements. This video shows our shutter working with the AO loop closed in the Solar tower in Arcetri, Italy. It was taken during the week after our pre-ship review.
The Strehl time series is derived from our custom wavefront reconstructor (calculations are done on a GPU). During this testing the shutter decisions were based only on the most recent Strehl measurement, meaning that we did not use any predictive algorithms. Note the fleeting moments of a clear Airy pattern as the shutter finds the highest peaks in the Strehl ratio time series.
The real question is: does it do any good? We’re still analyzing all the data we took, but for now this demonstration is an important step showing that our telemetry and hardware systems can do real-time frame selection.
The MagAO project hosted our Pre-Ship Review (PSR) last week at Arcetri Observatory in Florence. The purpose of this review was to ensure that lab work on the AO system is complete and that MagAO is ready to move to the telescope for on-sky commissioning.
Six external reviewers (4 in person and 2 by videocon) gave us their time and attention for 2 days in real time, as well as studying up beforehand and writing a report after the fact. The scope of their expertise covered subjects from large telescopes, commissioning AO systems, instrument development, logistical implementation, real-time software, and adaptive secondaries.
The review lasted 2 days and included presentations, discussions, and a demonstration of the AO system in the tower, controlled from the chem. lab. Topics included a description of the Magellan telescope, an overview of the MagAO project and instrument, the scientific justification, detailed technical descriptions of all subsystems, logistical considerations, and our plans for commissioning. The reviewers considered everything in detail and gave us a report in the format of Findings, Comments, and Recommendations.
The review went very well — the reviewers were extremely thorough and helpful. They included three requirements and four recommendations, as well as findings and comments. We are working to address the requirements identified by the panel, before we ship to Chile. Two have been addressed already this week, and the third is waiting for next week.
Here are some photos from the review:
Due to the always too short amount of time we get to spend with our instrument here, we work some long hours. Late at night and on weekends the front gate to Arcetri is closed, so we have to go around the back way. It is actually a nice walk, and we discovered the last remaining snow in Florence. In the picture you can see the top of the Solar Tower, where our adaptive secondary mirror is mounted. It is performing very well, and we are putting the last touches on the amazing automation that was developed here at Arcetri.
The MagAO team (or at least part of it) has returned to Florence for another round of integration and testing. I (Jared) have been here for 2 weeks, and Laird and Derek just arrived. As soon as I arrived we successfully closed the loop again, with only minimal adjustments of the alignment using the X-Y-Z stages. The system came right back up, with less than 5 minutes of work, after 3 months of down time.
The last two weeks have been mostly uneventful, consisting of a lot of software development and debugging. In preparation for the next 2 weeks of work on the ASM and the CRO tests we removed the NAS from the tower on Friday. The two videos below show the process of lowering, and then tilting the NAS upright on its handling cart.
While the NAS is off the tower we will be fine tuning the WFS and VisAO camera alignment, as well as testing the AO to Magellan software interface. In about two weeks we’ll reverse the process, and mount everything back in the tower for some more exciting closed loop action.