MODS  Controller Upgrade – Instrument Availability Delayed
update: Jan 19th

The MODS instruments underwent controller upgrades this summer, replacing the legacy head electronics and a set of aging computers. These upgrades were carried out to ensure the long-term reliability, robustness, and stability of the instruments. Additionally, preliminary testing shows a significant reduction in readout overheads.

Both MODS are mounted on the telescope. The AGW checkout, which uses just the guide and wavefront sensor cameras, was completed during the ECD nights on Dec 23 and Dec 31 UT, and much progress was made at the start of 2026 with closed dome tests of the IMCS (image motion control system) and the data acquisition chain from detector to archive staging disk. 

On Jan 19 UT, we collected on-sky data with the MODS detectors for the first time since the upgrade. Imaging and acquisition scripts were successfully run through the GUI in monocular and binocular mode, and the updated display and alignment software tools were used. Data for an AGW stage to PCS transform were collected. There is still work to do to address issues that arose and to refine the controller configurations for reading out the detectors, so MODS is not yet ready for science. Much of this work can be done closed-dome, and the next ECD night will be on Feb 1 UT.