If you are new to cameras, let me give you a quick tip for the holidays.
When you shoot pictures of your family, use “slow flash” (enable “slow” on Nikon, or use Av mode on Canon) and an ISO of 400 or even more if it is dark indoors. That allows the background light to show, as well.
You will need flash, too, around the tree. But rather than the popup flash, use an external flash. And above all, do not do this with that flash:
Instead, do this:
That’s right – point the flash backward above you. Your happy snaps (photojournalists call them “grip and grins”) will be infinitely better.
Is that a trick that only the 580 EX II can pull off?
Nope: the 430ex can do that just as well. As can the 420 (the older version of the 430).