1. save ps files
set_plot,'ps'

device,filename='a.ps',/portrait,xsize=5,ysize=5,$
xoffset=2.5,yoffset=10.,bits_per_pixel=16

device,/close
set_plot,'win'; for windows
set_plot,'x'; for Linux

2. to avoid idl graphs to be erased
device,retain=2

3. download SDO/AIA fits files
 - go to <a href="http://jsoc.stanford.edu/ajax/lookdata.html" target="_blank">JSOC data page</a></p>
 - enter keywords to get the data, e.g. aia.lev1[2012.03.03_17:40_TAI/240m][? WAVELNTH = 304 ?]{image_lev1}
 - export the data as "url", providing the email address, it will give a requesting ID, wait
 - after processing is completed, go to the url address it gives 
 - use "wget" to download the fits files into a local directory, e.g. wget -c -r -A .fits url