Project

General

Profile

Cal-G5

"We have initial measure of what RASICAM outputs are indicative of >0.01 mag degradation of relative photometry across FOV."

Prerequisites

  • Working RASICAM images and quantitative outputs from it.
  • Accurate starflat and ubercal-type solutions for many overlapping exposures in Minisurvey or other fields.

Procedure

  • Examine each exposure for variation of relative photometric residuals across the FOV (or e.g. if independent zeropoints per CCD per exposure, find exposures where CCD's zeropoints are not varying in concert). Assign some value of photometric inhomogeneity to each exposure.
  • Correlate photometric inhomogeneity with RASICAM quantitative outputs.

Verdict

  • Determine RASICAM outputs that are indicative of measurable photometric inhomogeneity

Consequences

  • Can be used in future ubercal / photometric solutions to determine when relative photometry should be reliable across full FOV. No corrective actions on hardware.