I have a D70 with the "kit" 18-70 zoom. I'm getting a 70-300mm f/4.0-5.6D ED. I want one more - what should it be? The objective is to cover low-light and indoor situations, museums, people etc. It needs to cost no more than the 70-300. I'm considering the 50mm f/1.4D, or 50mm f/1.8D. I'm just an amateur, not a pro. My wife and I do a lot of travel, I take landscape/animal/flower pictures, and my wife drags me to museums quite a bit. Comments? Suggestions? Anything else I should consider? Thanks in advance for your opinions.