During the fireworks, think about using a remote so you can see the whole view, rather than the small picture that you might get in the viewfinder or screen. It can also help you keep your image steady. If you want to purchase sparklers online then you can navigate various online sources.
You can try the difference between the image vertically and horizontally-block, depending on the altitude fireworks and how much the landscape that you want in your shot.
Also, consider having a long shutter opening. When you have long shutter speed, you can track the appearance and fall like sparks fireworks colorful drift downward. This can help you with your time well so you do not try to predict when that you must click your shutter.
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You can also take steps to ensure a favorable setup. Before the fireworks, scout locations and try to find a place that will allow you maximum visibility. Check out the horizon of your shots so you do not try to figure out the straight lines of the horizon in the dark.
Also, you may use a tripod to help you keep your images from scratch. Utilizing a tripod or other stabilizing device can keep the cameras from squiggling lines of fireworks when you use slower shutter speed.