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Video astrometry of comet C/2017 T2 (PanSTARRS)

Watec 910 video camera
IOTA-VTI GPS time inserter
OccuRec (recording)
Tangra (reduction)
Comet C/2017 T2 (PanSTARRS) has been trundling through the northern constellations for several months and I've been doing astrometry of it since late October 2019. I've obtained 90 measures of its position on 32 nights. The comet reached perihelion on May 4 when it was 1.6 AU from the Sun.
I downloaded all astrometry for this period from the MPC website (including my own) and processed them with online Find_Orb to determine the RA and Dec residuals for each observation. The attached plots show the astrometric residuals (arcsec, in RA and Dec) for all CCD measurements (in grey) and video measurements from my location, Z92 (in black). It's interesting to see the comet's movement in recent weeks, meandering around its mean nominal position.
C/2017 T2 is now nicely located above the Plough asterism and I hope to measure it for some weeks yet.