Allow translator subclass to specify list of on-sky observation types

python/astro_metadata_translator/translator.py

@@ -141,6 +141,16 @@ class MetadataTranslator:
     `PropertyDefinition`.
     """
 
+    _sky_observation_types: tuple[str, ...] = ("science", "object")
+    """Observation types that correspond to an observation where the detector
+    can see sky photons.  This is used by the default implementation of
+    ``can_see_sky`` determination."""
+
+    _non_sky_observation_types: tuple[str, ...] = ("bias", "dark")
+    """Observation types that correspond to an observation where the detector
+    can not see sky photons.  This is used by the default implementation of
+    ``can_see_sky`` determination."""
+
     # Static typing requires that we define the standard dynamic properties
     # statically.
     if TYPE_CHECKING:
@@ -1245,9 +1255,9 @@ def to_can_see_sky(self) -> bool | None:
         if obs_type is not None:
             obs_type = obs_type.lower()
 
-        if obs_type in ("science", "object"):
+        if obs_type in self._sky_observation_types:
             return True
-        if obs_type in ("bias", "dark"):
+        if obs_type in self._non_sky_observation_types:
             return False
         return None
 

python/astro_metadata_translator/translators/decam.py

@@ -80,6 +80,10 @@ class DecamTranslator(FitsTranslator):
     # the same offset used by the Vera Rubin Observatory of 12 hours.
     _observing_day_offset = astropy.time.TimeDelta(12 * 3600, format="sec", scale="tai")
 
+    # List from Frank Valdes (2024-03-21).
+    _sky_observation_types: tuple[str, ...] = ("science", "object", "standard", "sky flat")
+    _non_sky_observation_types: tuple[str, ...] = ("zero", "dark", "dome flat")
+
     # Unique detector names are currently not used but are read directly from
     # header.
     # The detector_group could be N or S with detector_name corresponding