The lamp PF varies also by the individual lamp spec within the same lamp type. The ballast have some losses that vary by lamp type and power, and by the ballast efficiency class. Those two would further close the gap between the current calculator results and the standard specs
For ballasts here are some examples i recall (all 230V 50Hz chokes)
FL 36W T8/40W T12 :
- ~1960s 70s ballasts : Seen 10W quoted in a book printed in the early 80s, but i think that "open core" ballasts (which production was ending around that time, but were probably still the most common in installed luminaires) may be less efficient than this
- Standard from the 80s onwards : Typical 8W
- Lowloss from the 80s onwards : Typical 6W
MBF 400W (used also for Halides) :
- Seen 40W in multiple sources. Probably does not vary that much between old and new ballasts
For a fairly big set of measurements of ballasts (power consumption of lanterns or other luminaires) go to Mike Barford's site at https://streetlightonline.co.uk/ , go through the lanterns and other luminaire types in the collection
The website you used for the calculator seems to replicate some of the features of Kmplot - a local (offline) program that has drawing plots with parameters and an expression calculator
for example F40T12 103V 430mA PF 0.87 220V Mains gives me an impedance of 402 Ohms,