Merge pull request #503 from lsst/tickets/DM-49576

DM-49576: Compare DateTimes for straylight

Author: timj

python/lsst/obs/subaru/strayLight/yStrayLight.py

@@ -16,13 +16,13 @@
 
 __all__ = ["SubaruStrayLightTask"]
 
-import datetime
 from typing import Optional
 
 import numpy
 from astropy.io import fits
 import scipy.interpolate
 
+from lsst.daf.base import DateTime
 from lsst.geom import Angle, degrees
 from lsst.daf.butler import DeferredDatasetHandle
 from lsst.ip.isr.straylight import StrayLightConfig, StrayLightTask, StrayLightData
@@ -33,6 +33,10 @@
 
 BAD_THRESHOLD = 500  # Threshold for identifying bad pixels in the reconstructed dark image
 
+# LEDs causing the stray light were been covered up by his date.
+# We believe there is no remaining stray light.
+_STRAY_LIGHT_FIXED_DATE = DateTime("2018-01-01T00:00:00Z", DateTime.UTC)
+
 
 class SubaruStrayLightTask(StrayLightTask):
     """Remove stray light in the y-band
@@ -61,9 +65,7 @@ def check(self, exposure):
         if detId in range(104, 112):
             # No correction data: assume it's zero
             return False
-        if exposure.getInfo().getVisitInfo().getDate().toPython() >= datetime.datetime(2018, 1, 1):
-            # LEDs causing the stray light have been covered up.
-            # We believe there is no remaining stray light.
+        if exposure.visitInfo.date >= _STRAY_LIGHT_FIXED_DATE:
             return False
 
         return True