Merge pull request #412 from lsst/tickets/DM-50838

DM-50838: Add monitoring of HVBIAS keyword for IsrTaskLSST.

Author: erykoff

python/lsst/ip/isr/isrMockLSST.py

@@ -820,6 +820,7 @@ def makeImage(self):
             exposure.variance.array[:, :] = np.abs(np.median(exposure.image.array)/10.)
 
         exposure.metadata["BSSVBS"] = 50.0
+        exposure.metadata["HVBIAS"] = "ON"
 
         if self.config.doGenerateAmpDict:
             expDict = dict()

python/lsst/ip/isr/isrTaskLSST.py

@@ -271,6 +271,12 @@ class IsrTaskLSSTConfig(pipeBase.PipelineTaskConfig,
         doc="Back-side bias voltage header keyword. Only checked if doCheckUnprocessableData is True "
             "and bssVoltageMinimum is greater than 0.",
     )
+    hvBiasKeyword = pexConfig.Field(
+        dtype=str,
+        default="HVBIAS",
+        doc="Back-side bias voltage on/off header keyword. Only checked if doCheckUnprocessableData is True "
+            "and bssVoltageMinimum is greater than 0.",
+    )
 
     # Amplifier to CCD assembly configuration.
     doAssembleCcd = pexConfig.Field(
@@ -1748,7 +1754,15 @@ def checkBssVoltage(self, exposure):
             )
             return
 
-        if voltage < self.config.bssVoltageMinimum:
+        hv = exposure.metadata.get(self.config.hvBiasKeyword, None)
+        if hv is None:
+            self.log.warning(
+                "HV bias on %s not found in metadata.",
+                self.config.hvBiasKeyword,
+            )
+            return
+
+        if voltage < self.config.bssVoltageMinimum or hv == "OFF":
             detector = exposure.getDetector()
             raise UnprocessableDataError(
                 f"Back-side bias voltage is turned off for {detector.getName()}; skipping ISR.",

tests/test_isrTaskLSST.py

@@ -2085,6 +2085,99 @@ def test_overrideMaskBadAmp(self):
         mask_array = result.exposure.mask.array
         self.assertFalse(np.all((mask_array & bad_mask) > 0))
 
+    def test_hvBiasChecks(self):
+        """Test the HVBIAS checks."""
+        # We use a flat frame for this test for convenience.
+        mock_config = self.get_mock_config_no_signal()
+        mock_config.doAddDark = True
+        mock_config.doAddFlat = True
+        # The doAddSky option adds the equivalent of flat-field flux.
+        mock_config.doAddSky = True
+
+        mock = isrMockLSST.IsrMockLSST(config=mock_config)
+        input_exp = mock.run()
+
+        isr_config = self.get_isr_config_electronic_corrections()
+        isr_config.doBias = True
+        isr_config.doDark = True
+        isr_config.doFlat = False
+        isr_config.doDefect = True
+
+        # Set the voltage.
+        input_exp.metadata["HVBIAS"] = "OFF"
+
+        # Check that processing runs with checks turned off.
+        isr_config.doCheckUnprocessableData = False
+
+        isr_task = IsrTaskLSST(config=isr_config)
+        with self.assertNoLogs(level=logging.WARNING):
+            _ = isr_task.run(
+                input_exp.clone(),
+                bias=self.bias,
+                dark=self.dark,
+                crosstalk=self.crosstalk,
+                ptc=self.ptc,
+                linearizer=self.linearizer,
+                defects=self.defects,
+                deferredChargeCalib=self.cti,
+            )
+
+        # Check that processing runs with other way of turning checks off.
+        isr_config.doCheckUnprocessableData = True
+        isr_config.bssVoltageMinimum = 0.0
+
+        isr_task = IsrTaskLSST(config=isr_config)
+        with self.assertNoLogs(level=logging.WARNING):
+            _ = isr_task.run(
+                input_exp.clone(),
+                bias=self.bias,
+                dark=self.dark,
+                crosstalk=self.crosstalk,
+                ptc=self.ptc,
+                linearizer=self.linearizer,
+                defects=self.defects,
+                deferredChargeCalib=self.cti,
+            )
+
+        # Check that processing runs but warns if header keyword is None.
+        isr_config.doCheckUnprocessableData = True
+        isr_config.bssVoltageMinimum = 10.0
+
+        input_exp2 = input_exp.clone()
+        input_exp2.metadata["HVBIAS"] = None
+
+        isr_task = IsrTaskLSST(config=isr_config)
+        with self.assertLogs(level=logging.WARNING) as cm:
+            _ = isr_task.run(
+                input_exp2,
+                bias=self.bias,
+                dark=self.dark,
+                crosstalk=self.crosstalk,
+                ptc=self.ptc,
+                linearizer=self.linearizer,
+                defects=self.defects,
+                deferredChargeCalib=self.cti,
+            )
+        self.assertEqual(len(cm.output), 1)
+        self.assertIn("HV bias on HVBIAS not found in metadata", cm.output[0])
+
+        # Check that it raises.
+        isr_config.doCheckUnprocessableData = True
+        isr_config.bssVoltageMinimum = 10.0
+
+        isr_task = IsrTaskLSST(config=isr_config)
+        with self.assertRaises(UnprocessableDataError):
+            _ = isr_task.run(
+                input_exp.clone(),
+                bias=self.bias,
+                dark=self.dark,
+                crosstalk=self.crosstalk,
+                ptc=self.ptc,
+                linearizer=self.linearizer,
+                defects=self.defects,
+                deferredChargeCalib=self.cti,
+            )
+
     def get_mock_config_no_signal(self):
         """Get an IsrMockLSSTConfig with all signal set to False.