This is not for the faint hearted, so any doubts whatsoever do not
even attempt it.
It is actually quite simple and straightforward, but if you don't
understand it it's likely best not to try it.
Now, this past couple of days VizieR has upgraded the SDSS data
release 3 photometric catalogue to data release 4, dr 4.
This will show a way of downloading and displaying these objects, the
display giving the SDSS magnitudes, their errors, positional
information, date of observation, a link to a more in depth page on
the SDSS server, inclusive of an image, and the automatically
estimated type of object.
First you need to download sdss.zip from the Guide-user yahoo groups
file section
http://tech.groups.yahoo.com/group/guide-user/files ,
it's been successfully passed on a virus test this end, but feel free
to test it again.
Now to the procedure :-
[Note that if any of this goes wrong, simply reinstalling the latest
Guide 8 update you are using from Guide8.zip will fix all and return
things back to as was.]
Find gsc22.exe in your Guide directory and _copy_ it to the UTILS
subdirectory that lies within the Guide directory. It is important to
ensure you do not move it, you need to have gsc22.exe existing in both
the GUIDE directory and the GUIDE/UTILS directory. Think of it as
your backup of gsc22.exe.
Copy s.exe to this UTILS directory.
Copy sdssdr4.tdf to the Guide 8 directory.
Copy sdss.bmp to the Guide 8 directory.
sdssdr4 can be copied to the Guide 8 directory or not, it is merely
some predownloaded data for testing the TDF and is not essential.
Future downloaded data files will be appended to this file, but if it
does not exist a new one should be made. However, if that doesn't
happen for whatever reason, including this file will give further
downloads something to append to. GO TO RA 172644.63+583745.8 to
test, clicking on coloured stars
Now to make some dos batch files, this is simple enough, and works on
my machine using win2k. Whether it works in ME or XP I don't know,
but it should work in any Windows flavour that is capable of launching
a dos box. The batch files will be accessed via
START in bottom left of screen, normally, far left of Task Bar
RUN
In RUN entering s in the dialogue box and pressing okay will turn on
SDSS download, entering g will put things back to default.
Open Notepad
enter the following lines, adapted for your computer
@echo off
copy d:\fullpath\guide\utils\s.exe d:\fullpath\guide\gsc22.exe
if you store guide in a drive different from D:, edit accordingly, and
replace the words "fullpath" with the full file path to your Guide
directory.
The simplest version would be c:\guide\gsc22.exe for example for
someone who has isntalled Guide directly to drive C:
Save those two lines as a file named s.bat in your Windows directory!
That'll be in c:\windows or c:\winnt or similar. It can alternatively
be saved in the system32 directory. Basically any directory that is
listed in the system variables' path will suffice for those in the
know, otherwise just do the above.
Do all the above with a second file except in Notepad type
@echo off
copy d:\astro\guide\utils\gsc22.exe d:\astro\guide\gsc22.exe
and save it as g.bat in the windows or other appropriate directory.
Now to edit TOOLBAR.dat. You may wish to make a copy of this and call
it toolbar.bak first, however it is usually replaced with Guide 8
upgrade zipfiles anyway, so recoverable. Unless, of course, you keep
a personally modified version, then back it up.
At the top of Toolbar.dat is a number. In your text editor, possibly
notepad will suffice, increment this number by 1. ie if it says 0304
change it to 0305.
You can add the following line anywhere, but if you add it near other
internet download toolbar buttons it'll be easier to find in future.
So, in notepad for example, EDIT->FIND usno.bmp or gsc22.bmp or similar.
Insert a line and add in this line
2550 !sdss.bmp SDSS data via Internet
such that the local arrear of this list now looks something similar to
this
# 2161 !rs.bmp RealSky image
# 2119 !dss.bmp DSS image
# 2378 !gsc22.bmp GSC 2.2 data via Internet
# 2410 !web_dss.bmp Grab DSS image via Internet
# 2411 !web_a20.bmp A2.0 data via Internet
2550 !sdss.bmp SDSS data via Internet
2457 !usno.bmp B1.0 data via Internet
2458 !2mass.bmp 2MASS data via Internet
# 2413 !a10.bmp Get A1.0 data from CD-ROM
# 2414 !a10.bmp Get A2.0 data from CD-ROM
You will likely also have an UCAC2 data via Internet link, which I
have removed.
Save toolbar.dat
Basically this simply works because s.exe is a version of gsc22.exe
which has been hex edited to get sdss dr 4 data from vizier instead of
getting ucac2 data from vizier.
OPERATION
Guide will now have an SDSS toolbar button, possibly also an ucac2 one
depending on personal preference.
When s.bat is run by using START->RUN->s the file s.exe copies over
gsc22.exe such that when the SDSS toolbar button is pressed SDSS data
release 4 data is returned via VizieR. Incidentally, SDSS data
release 4 data will also be returned if the UCAC2 button is pressed in
this cirumstance. This is a dirty little kludge and simply replaces
the ucac2 fetch with an sdss fetch. There is no download progress box
for SDSS retrieval, incidentally.
To return Guide 8 to UCAC2 download simply use START->RUN->g which
copies the default gsc22.exe stored in the UTILS directory back into
the Guide directory and returns the normal situation. Again, in this
situation pressing on the SDSS button returns UCAC2 data as does
pressing on the UCAC2 button. The 2550 tells you that in toolbar.dat
This is a _kludge_, not a fix or addition.
The SDSS data is returned as coloured stars where g' and r' are
interpreted as B and R using "photo" in the TDF as this seems to give
the most accurate matches. The stars are plotted to the r', or red,
mag. Right click gives mag info and object type and more info
additionally errors on mag and date when imaged and a link to the SDSS
data release 5 summary page and image for that star at the SDSS webserver.
SDSS data fills half the northern sky, plus an near complete
equatorial strip, is good between mags about 15 and 20+, and is of
decent astrometry, and better than USNO B1.0, so makes a nice
complement to UCAC2 where it is available, but avoids dense star
regions so lies mainly away from the Milky Way.
High quality V can be calculated for good g' and r' values using
V = r' + 0.44*(g'-r') - 0.02
for stars that are not too red.
Again, if you can see a need for this, try it, if it works, fine, if
not reinstall your personal latest upgrade file and ignore. Therefore
there must be a willingness and ability to reinstall the latest
upgrade file the user is using before any attempt is made to try this,
ie it's the users own responsibility, it's a kludge, if it doesn't
work you've to be aware of how to return to where you were.
On the other hand, it's simple and straightforward enough, if a little
fiddly, and it works a doddle, I've been using it ages (albeit with
vizier SDSS data release 3 until the data release 4 upgrade yesterday).
Finally, for those who can hex edit files, you could replace the sdss
vizier url, and download file name (sdssdr4), in s.exe with any other
vizier list, such as DENIS or CMC14, easily enough, but you'll have to
write a TDF to plot up the downloaded datafile in Guide and create a
.bmp file for the toolbar using 2550 as anchor, but most of the rest
of the above will be just the same, though s.bat and s.exe will no
longer be mnemonic, of course.
Cheers
John