You shouldn't use flash when you're taking a picture of fireworks or anything like that. The flash only works for things that are 15 feet away or closer, and if you use it for something that's further, the picture won't turn out. You should also use 400 speed film at night. Some people say you need to have 400 at night and a slower speed during the day, but I find that if you're not trying to take professional quality pictures and you don't want to enlarge your pictures to a really big size, 400 is fine all the time.