Re: [guide-user] DSS images

Bill J Gray Nov 25, 2003

Hi Mark,

A couple of things to try:

Zoom in _very_ far (say, one arcminute or so) and see if you can
get an image. The images tend to be bulky, and the server not very
brisk. Getting large images via Internet tends to be a pain.

If you don't have the Internet connection going, then just clicking
on "Get DSS Image via Internet" may not get it started. (Similarly
for other "get data via Internet" functions in Guide.) I think this
is mostly fixed, but if you find that your dialup (or similar) connection
doesn't do anything when using these functions, try starting up the
connection separately, and _then_ using the Guide function(s) to get
data via Internet.

In a similar vein, if you select DSS-1 (with pixels 1.7 arcseconds
on a side), your downloads will be faster than with the other surveys
(with 1.0 arcsecond pixels), because you're getting 2.89 times fewer
pixels.

Assorted servers have been known to be down at one time or another,
so "wait and try again" is an option. Also, try the other functions
such as "get A2.0" (or GSC2.2, or 2MASS, or B1.0) "via Internet".
These use the VizieR or a different STScI server, so you may find
that they succeed. (Also, because they're just grabbing star
catalog data, they are much faster and can be used over wider fields
of view... not so many bytes to grab. And you'll get a progress
indicator, something that's not implemented yet for DSS images.)

Also, make sure that you have images turned 'on' and that they're
shown at your current field of view. (Controls for both of these are
given in the same "Extras... DSS/RealSky Images" dialog in which you
select the survey and click on "DSS via Internet".)

-- Bill