[Aavso-photometry] SX Lib sequence star 114!

[arne]

Yenal Ogmen wrote:
> Hi all,
> Last night I observed SX Lib through v-band and while doing photometry I realized that my check star's mag differs from its seq value. This is 114 star with seq value 11.355 for V-band. I checked my previous obs of field and I got approx. same value of 11.15. This means 0.2 mag of difference. This cant be due to error I think. I didnt submit this as an chart error and wanted to ask you all first. Anyone noticed this before?
> 
The 114 star, AUID  000-BBV-615, has B and V magnitudes as converted
from the Tycho2 catalog.  This is near the faint limit of Tycho2, as
evidenced by the quoted photometric error of 0.109mag.  I could believe
that its true magnitude is 0.2mag brighter than this.  Remember that
the original chart, a preliminary chart from 1981, had this star
with a magnitude of 10.6, so we are certainly closer to the correct
magnitude!  SX Lib is on the SRO calibration program and so all of
its photometry will be updated in a future release.
Arne