View source for Finding images using Skyview


Skyview pulls together some huge number of surveys in one place and makes them accessible to you in an easy, fast interface. It will resample and regrid and remosaic all sorts of surveys for you, from gamma rays to the radio. (That is, as we will see, both a strength and a weakness.) I don't know exactly if it conserves flux (e.g., if one can still do photometry off of the mosaics it provides); I would err on the side of caution and NOT use this for anything other than morphology, e.g., do science by eye with the mosaics, and you can use them for distance measurements on the images, but don't do photometry on these mosaics. 

For [https://skyview.gsfc.nasa.gov/current/cgi/titlepage.pl Skyview], you should use the full Query form, not Quick View and not Non-Astronomer's page. 

Skyview will always spawn the same second window for the results. The first time you call it, it will spawn a second browser tab or window (depending on your local configuration), and then, if you don't close that second tab or window explicitly, the next search results will go into that same window, even if it's hidden below where you are currently working. ''It will make it seem as if nothing has happened when you submit your search request.'' 

In Skyview, you can ask for more than one survey at the same time, but it uses the same 'common options' you specify on the query page. To select more than one survey that are not adjacent in the list, hold down the command key while clicking. (That is, at least, on a mac. Your mileage may vary.) 

Skyview will allow you to download both the JPG and the FITS file (click on "FITS" to download it). You want FITS, as per above. :)
The four most important parameter choices Skyview gives you are:
*center position 
*survey (wavelength) 
*image size in pixels 
*image size in degrees 

Skyview will happily and without complaint or warning resample and regrid the pixels to whatever scale you want. What do you need to do to get ‘native pixel’ resolution out of Skyview? You should figure out how many pixels you need to cover your region, and the native pixel sizes, so go and do the math, and ask Skyview to give you a full-sized image of your desired size. Note that you can request more than one survey at a time, but Skyview will use the same parameters for each of them.

If, in the future, you need to find Skyview, you will probably need to google "Goddard Skyview" as there is at least one other software package called Skyview (including one at IPAC that is mentioned more than once in the wiki) that does something else entirely.