Ever seen the moon HDR'd? Well now you have. I learnt that the moon is extremely bright so when your setting up for a set of bracketed shots, your shutter times need to be real quick. Otherwise you'll end up with an overexposed moon which has no detail at all. To force my exposure time down, I simply just adjust my exposure compensation. Quick shutter times were also a good thing because the moon moved surprisingly fast as it rose. When your shootin for HDR, the less movement an object makes the easier post processing becomes.