If I were going to an event like Comic-con, I'd take my D300, 17-55 2.8 and 85mm 1.8. Those two lenses would probably cover the vast majority of what I needed. I'd most likely live at around 800-1600 ISO, except while I was outdoors.
For a Nikon shooter, the 17-55 and 24-70 are the workhorse event lenses, along with older iterations of same. An indoor event is where something like a D700/5D Mark II earns its keep, particularly when paired with good glass.
But, pro-level glass is only the beginning. You have to know how to capture the images, or else all you're holding in your hand is a fine piece of craftsmanship and not much else.
For a Nikon shooter, the 17-55 and 24-70 are the workhorse event lenses, along with older iterations of same. An indoor event is where something like a D700/5D Mark II earns its keep, particularly when paired with good glass.
But, pro-level glass is only the beginning. You have to know how to capture the images, or else all you're holding in your hand is a fine piece of craftsmanship and not much else.