Nige,

That may be part of the problem. I have been trusting the camera to "choose" the appropriate exposure settings for me. I probably haven't been paying enough attention to what it is doing. Like I said, it works fine for using diffused and reflected light when I'm doing Macro work. I'm not sure if the problem is weak flash, poor geometry (I'm simply not getting the light to the subject), or poor exposure settings and am unsure how I should go about figuring it out.