Results of the PSF fitting procedure. (a) Component distance D as defined by Eq. (1). Open symbols indicate that the brightness relation between the components cannot be determined (overlapping error bars in panel b). (b) Absolute magnitudes: open symbols indicate that D < 0.04′′, implying significant PSF overlap; the denomination as “leading” and “trailing” components does not identify them as unique physical entities between epochs, because their relative position w.r.t. the heliocentric orbital motion changes as they orbit about each other. (c) Sky position angles (ccw from north) of the line connecting the components (black) and of the projected heliocentric orbital velocity vector of 288P (red). (d) Mean fit quality Q as described by Eq. (3). The horizontal lines indicate fit qualities where the model reproduces the data within 2σ and 3σ of the expected photon noise on average. Error bars on the data points are 3σ in panels a and c, 2σ in panel b, and 1σ in panel d.