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\IBVShead{4116}{24 November 1994}                      % Use it with dummy or empty arguments

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\centerline{\ft CF Cas = NSV\,14787}
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During my work on {\em PICA project\/} (Precise Identification and
Coordinate Adjustment of about 7000 variables) I have found that
{\em CF~Cas\/} is identical with {\em NSV~14787}.
 
{\em CF~Cas\/} = {\em 347.1931\/} = {\em SVS~256\/} is a well known
classical cepheid located in the open cluster NGC~7790. It was discovered
by Beljawsky (1931) and soon received its final designation (Guthnick,
Prager, 1934). From the time of its discovery the star was included in
many photometric and spectroscopic researches.
 
{\em NSV~14787\/} is listed as star No.\,750 in a catalogue of proper
motions of stars in the region of open clusters NGC~7788 and NGC~7790
(Ishmukhamedov, 1966). Neither chart nor equatorial coordinates were
published for this star in his paper. Later it was included in the New
Catalogue of Suspected Variable Stars (Kholopov et al., 1982).
 
While working on field variable stars around {\em QX~Cas\/} I have noticed
that coordinates reported in NSV for {\em NSV~14787\/} are about 1' north
of the star I have earlier identified as {\em QX~Cas\/}. To find additional
information, usable for correct identification, I have checked 
Ishmukhamedov's paper (the only one found for {\em NSV~14787\/} at all). He
gives there the used procedures and also a catalogue, listing star sequence
number, photographic magnitude, approximate {\em xy\/} coordinates in mm,
proper motion components and a short remark. From the {\em xy\/}
coordinates and magnitudes I have plotted a chart, covering field around
star No.\,750 (see Figure 1, in the middle). Comparison of this plot with
scanned paper copy of POSS plate O-1233 (Figure 1, left) gave following results :
\begin{list}{}{\itemsep=-1.5mm \leftmargin=6mm \rightmargin=0mm
   \itemindent=-6mm}
\item --- star No.\,692 without {\em var} remark was identified as
   {\em NSV~14781\/}.
\item --- star No.\,705 without {\em var} remark was identified as
   {\em CEab~Cas\/}.
\item --- star No.\,840 with {\em var} remark was identified as
   {\em QX~Cas\/}.
\item --- star No.\,750 = {\em NSV~14787\/} with {\em var} remark has no
   suitable optical counterpart at the plotted position.
\end{list}
From this it is clear that {\em NSV~14787\/} cannot be identical with {\em
QX~Cas\/}. From the comparison one can also see that the coordinates given
in NSV for {\em NSV~14787\/} are erroneous. So where is this star ?
 
Another comparison of plot and scanned POSS shows that while star
No.\,750 is superfluous in it's location, one bright star (by chance
variable {\em CF~Cas\/}) is missing on the plot. Close look shows that
plotted stars do NOT exactly match their counterparts on the sky. This can
explained partly by the fact that catalogue {\em xy\/} coordinates are only
approximate, having the precision stated to be 0.1 mm, but in fact a
bit worse. But such errors can't help us. Therefore I have checked the
whole catalogue for evident misprints -- and found 13 of these (stars
Nos.\,87, 113, 161-165, 282, 609, 793, 847, 1055 and 1072), out of 1088
listed stars. I have found also some other misprints in the text part so I
have checked the possibility there is a misprint in {\em xy\/} coordinates
of stars No.\,750 and I have found a solution. The printed {\em y\/}
coordinate is $-6.0$, while at $-2.0$ (and same {\em x\/} coordinate) is
the
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Left: Scanned POSS plate O-1233.  The picture was processed after
scanning to eliminate the faintest stars. Middle: Plot from catalogue of
Ishmukhamedov (1966). The open circle marks the position of star  No.\,750
on its original place. Right: Plot from GSC. Arrowed stars are CEab~Cas, CF~Cas,
QX~Cas and NSV~14781, while crossed circles mark the (bad) GCVS and NSV
positions for QX~Cas and NSV~14787. The area covered by all the charts
is the same -- about 15'$\times$20' with north up.
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Table 1. Comparative table of {\em original} data for NSV\,14787, 
GSC\,4281.1902, GSC\,4281.1230, CF~Cas and QX~And.
CF~Cas and QX~And. Data concerning NSV\,14787 are from NSV, data for CF~Cas and
QX~Cas are from GCVS, data for CF~Cas (Plaut) are by Plaut (1977) and data for 
GSC\,4281.1902 for GSC\,4281.1902 and GSC\,4281.1230 are from GSC.
Photometric system code 1 for GSC represents the Kodak IIa-D plate with W12 filter.
Coordinates printed in italics were computed from the above stated data sources.
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\noindent bright star, having up to this moment no counterpart in catalogue. I
suppose these stars are identical for these reasons :
\begin{list}{}{\itemsep=-1.5mm \leftmargin=6mm \rightmargin=0mm
   \itemindent=-6mm}
\item -- after correction the match with real star is quite good.
\item -- misprints are often in the paper of Ishmukhamedov.
\item -- star No.\,750 has a {\em var} remark and {\em CF~Cas\/} is
   variable.
\item -- the photographic magnitude of star No.\,750 does not contradict B
   magnitudes of {\em CF~Cas\/}.
\end{list}
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Summary information can be found in Table 1.
Following cross-identifications are valid:
\begin{list}{}{\itemsep=-1.5mm \leftmargin=6mm \rightmargin=0mm
   \itemindent=-6mm}
\item CF~Cas = 347.1931 = SVS~256 = NSV~14787 = Vat ph 23\fh 52\fmm
+61\degr No.\,39660 = \\
\hspace*{14mm}GSC~4281.1902\\
\item QX~Cas = SVS~969 = CSV~5816 = GSC~4281.1230
\end{list}
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% Call for macros \authors - \authorsrightcol - \endauthors
\beginauthors
\authorsrightcol
Jan M\' ANEK
\v Stef\' anik Observatory
Pet\v r\' \i n 205
118 46\ \ Praha Czech Republic
Internet : {\tt observ@earn.cvut.cz}
\endauthors

% Call for macro \references
\references

Beljawsky, S., 1931, {\it Astronomische Nachrichten}, {\bf 243}, 115

{\it Guide Star Catalogue v1.1}, 1992, {\it The Space Telescope Science
   Institute}, Baltimore, Maryland, USA, on CD-ROM

Guthnick, P., Prager, R., 1934, {\it Astronomische Nachrichten},
   {\bf 251}, 257

Ishmukhamedov, Kh., 1966, {\it Circular Tashkentskoi Astr. Observatorii},
   No.\,345

Kholopov, P.N., et al., 1982, {\it New Catalogue of Suspected Variable
   Stars}, Nauka, Moscow
   
Kholopov, P.N., et al., 1985, General Catalogue of Variable Stars,
   4th ed., Nauka, Moscow
   
Plaut, L., 1977, {\it Astronomy} \& {\it Astrophysics Suppl.}, {\bf 28}, 169

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