[vsnet-chat 1028] Re: [vsnet-obs 13026] Re: (fwd) On SV Sge magnitudes

[Taichi Kato <tkato>]

   The present problem reminds me of some previous occasions, both of which
were associated with R CrB-type(like) fadings.

   One example is FG Sge, for which we had been aware of the existence of
a close companion.  But the quoted magnitude of the companion in the GCVS
Remark actually confused observers.  The actual V magnitude is around 12.5,
while the GCVS statement suggested a magnitude around 14.  At the time of
the first fading of FG Sge, many visual observers (including me and my
friends) supposed FG Sge stuck around 12.5.  Another example was V482 Cyg,
for which we later knew the existence of a nearby confusing star.
Observations tended to disagree near minimum; this was even true for
photographic observations.

   I had experiences, on some occasions, that close doubles near the
visibility limit are easier to recognize than those of solitary stars having
equivalent magnitudes.  In making actual comparisons, this effect may have
led to brighter estimates than what the actual magnitudes of the component
were.  With the help of close (suitable) companion, I could even locate
the faintest variable, such as HT Cas in quiescence (IR Gem at intermediate
brightness, etc.).  These estimates (or detections) may have been biased
somewhat brighter.  This effect may explain some systematic tendency of
recent SV Sge estimates.

   The actual number of audiences of vsnet-obs is something around 240.

Regards,
Taichi Kato

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