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Summary of the validation testing performed on the Data Preview 0.2 processing.
1 Visit Plots¶
1.1 Initial Data¶
Initially the data in a number of precursor collections was studied while the plots were being developed. During this investigation an offset in the photometry was found as shown in the Figure below. This was then corrected for in the later processing.
Figure 1 This plot shows the magnitude offset for HSC data, while this is not the DP0 data it was processed with the same pipeline and shares the same issues.
This issue was fixed before the main processing began.
1.2 Large Scale Processing¶
Once the initial data had been studied the large scale processing started. Plots were made of this data at the visit level. Plots for one, representative, visit are included here.
Figure 2 The magnitude for a 12 pixel circular aperture - the PSF magntiude for stars and galaxies.
Figure 3 The magnitude for a 12 pixel circular aperture - the PSF magnitude for just galaxies.
Figure 4 The magnitude for a 12 pixel circular aperture - the PSF magntiude for stars that were used as calibration sources for the PSF.
Figure 5 The magnitude for a 12 pixel circular aperture - the PSF magntiude for stars.
Figure 6 The magnitude for a 25 pixel circular aperture - the PSF magntiude for stars and galaxies.
Figure 7 The magnitude for a 25 pixel circular aperture - the PSF magntiude for galaxies.
Figure 8 The magnitude for a 25 pixel circular aperture - the PSF magntiude for stars.
Figure 9 The sky distribution of the magnitude for a 12 pixel aperture - the PSF magnitude for galaxies.
Figure 10 The sky distribution of the magnitude for a 12 pixel aperture - the PSF magnitude for stars used as PSF calibration sources.
Figure 11 The sky distribution of the magnitude for a 12 pixel aperture - the PSF magnitude for stars.
Figure 12 The sky distribution of the PSF flux SN for all sources.
Figure 13 The sky distribution of the sky object fluxes.
This plots show that the offset seen before has been fixed and don’t show up any other obvious issues. Plots studying the ellipticity were also made and some examples are given below.
Figure 14 The sky distribution of E2 (2ixy/(ixx + iyy)) calculated for the PSF.
Figure 15 A scatter plot of E2 (2ixy/(ixx + iyy)) calculated for the CModel shape.
More plots are available for a variety of visits and can be viewed through the plot viewer in the u/sr525 collections.