A quick calculation of the IMC visibility:

Before power outage:

IMC refl when offline = 46.9

IMC refl when online at 2 W = 0.815

1 - 0.815/46.9 = 0.982

After power outage:

IMC refl when offline = 46.5

IMC refl when online at 2 W = 2.02

1 - 2.02/46.5 = 0.965

So we think we have lost 2.6% of the visibility