Add gamma_curve to metadata

src/openflexure_microscope_server/things/camera/picamera.py

@@ -718,6 +718,11 @@ class StreamingPiCamera2(BaseCamera):
             copy_from=self.default_tuning,
         )
 
+    @lt.property
+    def gamma_correction(self) -> float:
+        """Return the gamma correction from the tuning file."""
+        return tf_utils.get_gamma_curve(self.tuning)
+
     @lt.action
     def set_static_green_equalisation(self, offset: int = 65535) -> None:
         """Set the green equalisation to a static value.
@@ -931,5 +936,6 @@ class StreamingPiCamera2(BaseCamera):
             "exposure_time": self.exposure_time,
             "colour_gains": self.colour_gains,
             "analogue_gain": self.analogue_gain,
+            "gamma_correction": self.gamma_correction,
         }
         return state