Check out the QHY178M data; they both use the same Sony IMX178 sensor.
I see from published data (per pixel):
-20C .0058 e-/s
-15C .0067 e-/s
-10C .0070 e-/s
-5C .0085 e-/s
0C .0098 e-/s
+5C .0138 e-/s
+10C .0204 e-/sec
The knee appears to be about 0ºC; the dark current noise decreases slowy when colder than 0ºC and increases rapidly when warmer than 0ºC.
Chen
