I never really messed with Daz Studio much. I just don't like it.
As for what you want to do with Poser, believe you me, there's no shortage of information out there, and you can count on getting good answers to technical questions, right here.

Don't let what I said about the manual dissuade you though. It's all true, but I thought you ought to know, since you specifically asked about it. But the overall lack of detail in the Poser manual has been an issue for as long as Poser has existed. Like I said, it's gotten better, but it will never be a step-by-step "how to" to any great degree. Software manuals rarely are.

Simply put, the best resource is the internet and the forums, where it comes to Poser technical specifics. And, as I mentioned, seriously consider getting some photography and digital lighting books, or at least search the 'net for info. There's plenty out there.