All the photos in my gallery have the settings listed below them, and there's a ton of firework ones; you're welcome to browse through there to get some specifics. You can even search for "fireworks" and you'll find some of them - I'm still re-processing my photos from the last trip, and only those are properly keyworded, along with some local fireworks photos I've taken recently.
Here's an example:
16mm (Zenitar fisheye lens), ISO 200, 3-second exposure. Because it's a fully manual lens, it didn't report the F-stop, but it was probably F8, that's what I did most of my night shooting with as it's a pretty safe number where most lenses are at their sharpest.
I just noticed that that particular shot has a bogus shutter speed listed on my site - but it's right in the exif. If you're using Firefox, grab the "fxif" add-on (Google to find it); if you're using Internet Explorer (shudder), there's a stand-alone program that has an IE plug-in, I believe it's Opanda Exif. Either of these will let you right-click a photo on a web page and go into Properties to see exif data, if it's there.
Anyway, back on topic...
If you want to try the Contemporary, you can get good views of the Magic Kingdom from the fire escapes. However, they lock you out if you let the door close, so you can either have a sympathetic family member ready to open the door for you, or maybe jam something in to keep the door from latching. This shot was taken the morning of New Year's Day and someone had jammed a noisemaker in to keep the door open. Otherwise, you need to walk down many flights to ground level.
You could probably get some pretty nice fireworks shots from there. I also liked some that I took from the beach at the Polynesian, with them reflected in the water.
As for Fantasmic... that's tough, as it's dark
and far away. I didn't really even bother last trip; if I did try today, I'd probably use the 50mm F1.4 and either have small details or crop the photo. Ideally, you'll have a long
and fast lens (like a 150 or 200mm F2.8), but those can get expensive quickly, and I don't have anything like that. (Yet.

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