Further to my previous post, another fun thing you can do with firework photos is stacking them. I used the Startrails application to do this one; it's a very easy to use program designed for creating, well, star trails, but can be used for stacking subjects such as fireworks and lightning shots to great effect.
Just like star trails, this process relies on the camera not having moved or changed frame in any way. I had tilted my lens up after a few fireworks once I had a feel for how high they were going, so the shots before then were useless for the stack, but I didn't change anything after that.
There was a lot of trial and error - all the useful firework shots in one stack were too much, and I gradually whittled it down to the four that make up this stack.
The stacking process itself take more time the larger the photo, so I initially exported relatively small images of 1200 pixels high with a "quality" of 60 from Lightroom, so each stack was fast to compile. Startrails adds a ticky-box next to each image, so you can add and remove them to see what their impact is and I played with that for ages. Once I was happy I exported full size and high quality files and created the stack with that.
I also deployed another trick I've used before to get rid of aeroplane trails across my star trails - I have a custom adjustment brush setting in Lightroom of -4.00 exposure and -4.00 shadow. This blackens anything it touches. The stacking will only allow the brightest pixel through to the top, so brushing out planes streaking across my individual star trail photos effectively removes them from the stack. With this firework shot, I used the same brush to remove either the top burst or bottom fountain firework in some images, as the lower half especially was crazy with lights and sparkles. I also used it to blacken all the skies except one, to keep the moon and clouds clear.
Firework photo stacking is at its most effective in a large show where you have fireworks exploding in multiple locations - by stacking frames you can capture them all in one shot. This display only had one launching point but I still had a lot of fun with the photos from it... and from watching it too of course! I love fireworks.