Okay, so I guess there is little to worry about in terms of compensation.

I did end up on wiki on the photoresistor page
http://en.wikipedia.org/wiki/Photoresistor
where it describes 2 main types of photo electric devices

one type gooses the response to lower frequencies/wavelengths but I think this may allow some to read lower light levels but I'm still digesting it.

Sam, thanks for the encouragement.