When they talk about "mag" or sometimes "V-mag" they are usally 
referring to Visual magnitude. Just like it looks to eye. B-Vmag is 
usually the Color Index relating to blue. It is a number with the 
lower ones being more blue and higher more red. Photographic 
magnitude is how bright the star is to a camera. Sometimes referred 
to as Blue magnitude or B-Mag, not to be confused with B-V mag.
What all this means is:
"5- 8 F4.2 mag ci color index": translates to columns 5 through 8 
contain a floating point number with 4 digits and has 2 decimal 
places. This is the color index or B-V mag of the star.

"9- 14 F6.2 mag Ptm Photovisual magnitude" Would be columns 6 through 
14 contain a 6 digit floating point number with 2 decimals that is 
the B-Mag or photographic magnitude of the star.

Hope this helpes.

bob




--- In [email protected], "R Arber" <[EMAIL PROTECTED]> 
wrote:
> Hello,
> I'm finding when I try to match fields in window #3 in CatGen with 
catalog, i.e. I'm using <I/90  Positions of 502 Stars in Pleiades 
Region     (Eichhorn+ 1970)> that the CatGen fields, i.e Mag(mag); B-V
(mag); Mag B (mag); Mag R (mag)., do not match description as per the 
catalog.  
> As an example the catalog I-90 calls for: mag CI; mag Ptm., as its 
definition of magnitude, right? (Please see below):
>  5-  8  F4.2  mag     CI        Colour index
>  9- 14  F6.2  mag     Ptm       Photovisual magnitude
> 
> The preceding is an example of one situation in one catalog, I'm 
having other mis-matches in other catalogs.
> Is there a method of interpreting, or a glossary of terms of these 
many various field definitions that one encounters; so that the 
uninitiated can recognize and translate them so that they fit into 
the appropriate fields in CatGen.
> 
> Please accept my thanks for your kind help in advance,
> Thank you,
> Bob 
> 
> [Non-text portions of this message have been removed]



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