DP0 delegates will soon notice a new tutorial notebook appear in their tutorial-notebooks directory, titled 09_Single_Star_Lightcurve_with_Butler.ipynb.
This notebook will be presented during a breakout session at the DP0 Delegate Assembly on Fri Jul 30.
We know a lot of people want to do time-domain science with DP0, but first let’s set expectations.
- Multi-epoch forced photometry was not run in DP0.1, and so DP0.1 does not provide an accurate preview of how time domain science will be done with the LSST data products.
- The new notebook is a temporary work-around to be used for a small number of objects (one to ten), and it is very, very slow (~30 minutes per object).
- This notebook is not representative of how lightcurves will be served or accessed in later Data Previews or Operations. Using this notebook is not teaching you the “right” way to build LSST lightcurves.
- In fact, this new notebook was designed to clearly demonstrate the limitations of attempting to make LCs during DP0.1
The recommendation is that delegates interested in time-domain astronomy wait for DP0.2, or at least limit themselves to only examining a few objects. Consider sharing the few LCs that are made via the “delegate-contributions-dp01” repo (see the readme for instructions on sharing).
How will DP0.2 be different?
DP0.2 will contain a ForcedSource table that will contain lightcurves obtained by forcing PSF photometry at the positions of all Objects on both PVIs and Difference Images (where Objects are the union of detections on difference images and detections on deep CoAdds, and PVI stands for Processed Visit Image).