0 votes

I am unable to obtain the combined DECaLS, BASS, and MzLS photometry from the NOAO Datalab using the crossmatching tools or direct SQL queries.  According to the website, the BASS photometry (covering declinations > +29) should be included in Legacy Survey DR7, but queries against this database (such as the ls_dr7.tractor or ls_dr7.galaxy tables) return nothing for these higher declinations, where BASS covers.  Oddly enough, the Legacy Survey SkyViewer even shows the BASS images as part of the Legacy Survey DR6+DR7 when querying for a dec > +29 object, but the photometry measurement database itself does not seem to link up.  

Thanks a bunch!

by jnburchett (120 points) | 207 views

1 Answer

0 votes
Hi Joe,

   So Legacy Survey DR7 contains only DECaLS photometry, as per the description here: http://legacysurvey.org/dr7/description/ .  If you need BASS/MzLS photometry, then LS DR6 contains the latest photometry for the northern part of the LS footprint.  LS DR8 will be the first release that combines DECaLS with BASS/MzLS, stay tuned for its availability.  If you need combined measurements, then for the moment the thing to do is to query DR6 and DR7 separately.


Knut Olsen
by kolsen (2.7k points)

437 questions

451 answers


651 users

Welcome to Data Lab Help Desk, where you can ask questions and receive answers from other members of the community.