12 | | • In closed-loop, we optimize the PSF shape on SCICAM using the trial & error algorithm used by the LBTO team during LUCI calibrations changing M2 reference shape applying modes coefficients (this is the baseline approach). |
13 | | • We also perform the phase-diversity tests using the same light source and look at the NCPA output produced (in case the NCPA produced by the baseline approach is not stable enough for a longer period and/or if more correction seems necessary for high contrast). |
14 | | • Depending on the two results and the quality of PSF, we may choose one or the other or the combination of both. |
15 | | * There is also the NCPA test to be performed using the Wollaston prism + direct imaging in dual-band imaging mode. In the daytime, this may be performed using the ARGOS swing arm calibration unit light source (for zenith, and if required using RR on other elevation angles) |
16 | | • Note that we may do this for different elevation angles. |
17 | | |
| 12 | • Go to a specific elevation of the telescope. |
| 13 | * In closed-loop, the Arcetri team optimizes the PSF shape on the SCICAM using the trial & error algorithm (used by the LBTO team during LUCI calibrations) changing M2 reference shape applying modes coefficients. [Currently, this is the baseline approach]. |
| 14 | • For the same elevation, keeping the M2 flat, using the same source, perform the phase-diversity test script which will make use of the Wollaston prism and dual-band imagers lens configuration. Apply the obtained NCPA on the ALPAO DM within SHARK. Take SCICAM images to see the improvement. [In case the NCPA produced by the baseline approach is not stable enough for a longer period and/or if more correction seems necessary for high contrast, we will be implementing this approach (for which we will be using the star itself as the source during nighttime)]. |
| 15 | • Make the ALPAO DM flat and using the internal calibration sources, run the phase-diversity script. Apply the obtained NCPA on the ALAPAO DM. Take SCICAM images. Note that this NCPA correction does not account for any aberrations caused by the Dichoics and internal TT mirror within the deployable arm. [This NCPA will only be used if the previous two options are not possible or good enough for a given case/target.] |
| 16 | * Repeat these measurements for decided discreet zenith angles (or elevation of the telescope), SHARK-NIR DROT angle (fixed), and star (source) brightness. |