Left panel: image of the dwarf galaxy Do I taken with a Takahashi FSQ106 refractor at f/3.6 and a commercial CCD camera QHY90A on 27 November 2016 at the Avalon Merlino Remote Observatory. The total exposure times were 24 300 s in the Luminance filter. The field of view of this cropped image is 123′×123′ with a pixel scale of 2.89 arcsec pixel⁻¹ (credits: Matteo Collina & Giuseppe Donatiello). The inner zoomed panel shows the TNG g-band image of the galaxy (see Sect. 2.1). Right panel: r-band image of Do I obtained from GTC observations (see Sect. 2.2). The total field of view is 4.30′×4.30′. North is up, east is left.