Both the following images were done with ArtRAge 2.5 in about 40 minutes. The first one with light switch (F5) off and the second one with F5 on - my humble way of highlighting the value of F5.

Brook 1.0

Brook 2.0

P.S: As there was no indication to show about the on/off status of the light switch, I started making a small search. I could not get much info on its fantastic feature. Hope someone would come out with an exclusive post on F5 soon.