+Photodiode:
+5 V, 1M5 resistor + photodiode: voltage at the photodiode
+darkness: 3.71 V => 4.31 MOhm
+bathroom without lights, only outside lights: 3.68 V => 4.18 MOhm
+kitchen light: 3.29 V => 2.89 MOhm
+bathroom halogen lights 0.02 V => 6 KOhm
+battery light: 0.01 V => 3 KOhm