I have been downloading DR_7 and DR_6 images for the g, r, and z bands using the DataLab image query for a list of known objects using RA/DEC and I've been having a few issues.
1) For about 1/2 of the objects this is working great, returning the 5'x5' cutout, but for the others I am getting only small parts of the image. I thought this could be an edge issue at first but that shouldn't be the case for so many of them.
2) The images I downloaded are "N up, E right", instead of "N up, E left", is this how they are actually calibrated or is there an error in how I am downloading them?
3) For DR_6 I have been able to get images for the g and z bands but using the same coordinates and code nothing is returned for the r band.
Here is the code I am using:
DEF_ACCESS_URL = "http://datalab.noao.edu/sia/ls_dr7"
svc = sia.SIAService(DEF_ACCESS_URL)
fov = (5./60)
for ra,dec,ID in zip(R_A,D_EC,I_D):
imgTable = svc.search((ra,dec),(fov/np.cos(dec*np.pi/180),fov),verbosity=2).to_table()
sel0 = startswith(imgTable['obs_bandpass'].astype(str),'g')
sel = sel0 & ((imgTable['proctype'].astype(str)=='Stack') & (imgTable['prodtype'].astype(str)=='image')) # basic selection
Table = imgTable[sel] # select
row = Table
url = row['access_url'].decode() # get the download URL
urllib.urlretrieve(url, ID + "_g.fits")
Please let me know how I can resolve these issues.