Thanks for the extra info. So there isn't actually a bug here, I think, but there are some confusing points.
First, on the subject of the RA and Dec in the table that is returned, these are of the center of the tile that contains the postage stamp that you want. The default behavior of the SIA service is to query the image metadata table for any image that overlaps with the position and field of view that you gave, and then return the row for that table. That row will report the parent image coordinates. It also contains an entry in the access_url column that contains the URL needed to generate the cutout. So this notebook cell:
fov = 0.1
ra = 7.139569
dec = -1.180077
imgTable = svc.search((ra,dec),(fov/np.cos(dec*np.pi/180), fov),verbosity=2).votable.to_table()
generates a table that contains e.g. this access_url:
where your RA, Dec, and FOV parameters are in the arguments of the cutout URL.
To download the z-band image from this table, I did:
sel = (imgTable['prodtype'] == 'image'.encode()) & (np.char.startswith(imgTable['obs_bandpass'].data.data.astype('str'),'z'))
to select rows with 'image' as the prodtype and 'z' at the start of the filter name, and then:
Table = imgTable[sel]
row = Table[np.argmax(Table['exptime'].data.data.astype('float'))]
url = row['access_url']
img = io.fits.getdata(utils.data.download_file(url.decode(),cache=True,show_progress=False,timeout=120))
hdr = io.fits.getheader(utils.data.download_file(url.decode(),cache=True,show_progress=False,timeout=120))
to get the image and header for that image.
If you look at the header, you'll notice that there is no exptime keyword, which is because for these image stacks, that quantity is not well-defined (and so the table schema records it as zero). Instead, the units of the image are recorded in the BUNIT keyword as nanomaggys, hence what appear to be low counts.
Anyway, to your specific questions:
1. Yes, you have the correct service URL.
2. As you can tell from the table, the cutout is made available as a URL with parameters for the ra, dec, and FOV that you provide. You could e.g. access a list of these with wget or curl, or download them through your notebook and store in your VOSpace.
Hope this helps...