A very interesting experiment with light. It may be even more effective if you could get the dark background more truly black and fill the frame completely with the sparks.
I found that "Fireflection" is very creative and original picture. Well done! Good for a desktop. You can play with dark and light color if you wish. I love this work. Thanks for sharing.
It's an interesting picture; reminds me of the county fair. Was your camera on a tripod? It seems as if it wasn't. I think if you had lowered the shutter speed with it on a tripod there would be less.. blur, maybe? I don't know, maybe it's just the wind blowing the fireworks around. I like it, either way.