(a) Photograph of the system in its MacroZoom configuration (b) Zoom-in on the core system with labeling of the core parts; galvanometric mirrors (Galvo xy) for tracking, the electrically focus-tunable lens (ETL) for focusing, as well as the objectives used for excitation and detection by the two imaging channels (Beam splitter (BS) and dichroic mirror (DC)) (c) Drawing of the main components and the optical path to supplement the schematic in Figure 1. The inset on the upper right shows galvanometric scanning of a transparent composite resolution chart (with a fluorescent plastic slide placed underneath, 1951-USAF part: 3.7 x 3.7 mm) via the 15-fold magnified fluorescent channel. Individual tiles were acquired with overlap to allow for image stitching as shown below. The image on the lower right shows cellular features resolvable in a reporter line with sparse labeling of neurons throughout the anterior-posterior axis tg(OMP4; GCaMP1.6 x mnGFF7; UAS:eGFP). The scale bars represent 100 μm. All parts of NeuBtracker are compiled in a parts list that can be found in Supplementary Table 1 and together with 3D CAD assemblies on neubtracker.org.