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A Multi-Conjugate Adaptive Optics (MCAO) testbed has been developed at the Instituto de Astrofísica de Canarias (IAC) as a prototype of the Adaptive Optics (AO) system for the European Solar Telescope (EST). EST is a 4.2-m telescope that will provide high resolution in a 60 arcsec circular Field of View (FoV). For this purpose, EST will be equipped with an MCAO system that will be integrated into the telescope's optical path. The aim of the testbed is to analyse different sensing and wavefront correction strategies in order to check their suitability for EST. The testbed is a downscaled version of the telescope that has been designed to replicate its main features, including the telescope aperture, the FoV and the atmospheric conditions representatives of the telescope site. It allows to set up of Single Conjugate Adaptive Optics (SCAO), Ground Layer Adaptive Optics (GLAO) and MCAO configurations, both for point-like and extended sources. For this purpose, three Shack-Hartmann Wavefront Sensors (SH-WFSs) have been developed and installed in the testbed. A High-Order Wavefront Sensor (HO-WFS) with 33x33 subapertures senses the on-axis 10 arcsec FoV. Additionally, a Multi-Directional WFS (MD-WFS) estimates the turbulence over the entire atmospheric volume. This WFS provides two possible configurations: one high-order spatial resolution (HO-MD-WFS) and another low-order spatial resolution (LO-MD-WFS). A pupil-conjugated deformable mirror (DM) with 820 actuators is currently available for SCAO and GLAO configurations. The introduction of two DMs conjugated to different altitudes will allow the correction of the wide field. The main aim of this contribution is to present the current state of the testbed and the first tests using a Multi-Directional WFS to perform the wavefront reconstruction. The test results show a possible approach to analyse the behaviour of the control loop of an adaptive optics system. It is discussed whether control quality metrics can be used as an alternative to classical optical quality metrics that are especially hard to standardize for solar observation. These metrics are relevant due to the amount of data for GLAO.
