Hmmm... why no more answers on this? I'm at work so I can't open my Poser7 to check, but if I remember correctly you will find the adaptation threshold in the Parameters, on the Render tab.

"If I were a shadow, I know I wouldn't like to be half of what I should be."
Mr Otsuka, the old black tomcat in Kafka on the Shore (Haruki Murakami)