Affiliation
American Association of Variable Star Observers (AAVSO)
Tue, 09/16/2014 - 20:56
I tried accessing five of the Landolt Fields listed at - http://www.aavso.org/standard-stars-vsp - using VSP and selecting a standard field chart. All came up empty... Is there a change to the fields currently in VSP?
Hi Gordon,
Those fields were entered before we created the "standard field" clickbox on the VSP input form. So you need to do two things:
1) select the field by entering RA and DEC of the center; the field name is not implemented yet.
2) do NOT click on the standard field option. The normal comp stars that show on the chart will have notes in the photometry table indicating that they are Landolt standards.
We will clean this up in the near future.
Arne
Gordon:
There are comps just NOT standard comps. Uncheck standard comps. This relates to a difference in terminology at this point. So far only M67 and NGC 7790 have standard comp fields. Four more open clusters will have standard comps at some point. Not Landolt fields.
BTW, since the Landolt fields have generally small numbers of standard comps, I think they will be of limited use for tranforms with PTGP.
Comments?
Ken
Ken,
Thanks. After looking deeper I realize you're right, there are not enough standard stars in most of the fields to make them useable for creating transforms. So I'm going to hold up adding any of them to PTGP unless directed otherwise. I'll wait for the four other open clusters you mentioned. Now that PTGP directly accesses VSP, adding additional standards fields will be quite easy.
Gordon