metpaper@Safe-mail.net Mar 4, 2012
> NOW, the main reason for this update though is the above file is also for running PPMXL from hard disk. The data files for PPMXL can be downloaded here :-
>
> ftp://cdsarc.u-strasbg.fr/pub/cats/I/317/dat/
>
> the tdf is expecting them to live in guide\ppmxl\ subdirectory, the tdf of course goes into the Guide directory, and contains links to the ppmxl data as well as the vizier download...
>
> But not fully. For various reasons I use UCAC2, not 3, and CMC14. These end at about 50 degrees North declination. Previously I used UCAC3, once it became available, North of there. UCAC3 takes a lot of cleaning and special care, such as Bill has taken with the Guide 9 DVDRom version.
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> I've got fed up with it. PPMXL is also "better" than USNO B1.0 as it has USNO B1.0 object linkage via 2MASS (ties it down better, gives 2MASS J and K magnitudes as bonus info) where stars are bright enough, and makes some attempt to merge the false multiple entries into one object at the faint end.
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> So, the tdf in the above zip file only works for +50 degrees to the North Celestial Pole. This was a download of only a few Gigs, and takes up 13.4 Gb of disk space. UCAC2 and CMC14 look after most of what else I need, with PPMXL from vizier should I need to go fainter (I also have USNO A2.0 on hard disk).
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> Anyone preferring full PPMXL to full USNO B1.0 on their hard drive can use the above. If the ppmxl files are placed elsewhere rather than in the guide directory, the lines beginning with the word "file" need to point to them, have the pathname to them.
>
> And the above tdf can be extended all sky by just adding the entries for each additional PPMXL dat file. These can be entered at the end, but the end tdf segment is for the vizier download of ppmxl, so you may want to include them just before that one in order for ease of finding things, though if one segment works, they all should, as long as you include all the file names and just once for each.
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> Full download is ostensibly 39 Gb utilising 89 Gb of hard disk space. Given some drives nowadays, and their speeds, this isn't too evilly bad. Guide can cope with big datasets very well anyway, and has done so for a long time, as it takes note of where you are looking and only looks through data relevant to that point. Having said that I have not bothered using the declimit command here as things are fast enough without it.
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> I've used automag filtering you see.
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> Right click and More Info and outlinking are just as with the vizier version.
>
> Cheers