I've been using the AAVSO target tool to work out a program of observations and I've noticed that there are discrepancies between the magnitude range quoted in VSX and that of the target tool. Although the discrepancies are not great they are significant. I had assumed that the target tool would pick up magnitude data from VSX data base but it seems not. Some examples are -
s cep (12.9-7.4) (12.5-6.6)
w cas (12.5 7.8) (13-8.2)
w per (11.8-8.7) (11.0-8.6)
They are all quoted as V filters. The first pair comes from the AAVSO target tool and the second pair from VSX.