Love the moored lobster boats lit up and town lights. How did you set the exposure?
A little bit of luck on the exposure. I was trying to get the harbor shot primarily, with the fireworks not the overwhelming subject.
I had my digital SLR on a tripod, set on Auto exposure - no flash. I knew the camera would choose the fastest ISO(1600), the widest aperture on my lens (F4.5-22mm lens).
I left the shutter speed choice up to the camera and manually focused the lens. Then it was just timing on my part, when to (gently so not to blur) press the shutter.
Because you asked (thank you!), I went through about 30 exposures I made of the fireworks. The only exposure variables, were the shutter speeds.
Most shutter times averaged around 1/3 rd of a second exposure and most were so-so shots(typical fireworks frozen in time).
THEN I noticed that in the posted shot, the camera chose a 2 second shutter speed. The camera chose the longer exposure because I squeezed the shutter just before the fireworks lit the sky up and the light meter saw less light.
That extra exposure time achieved a better lighting of the harbor(which was pitch black) and softened the fireworks as they overexposed a bit and gave them a little motion. There's a lot of luck in photography, at least in mine.
Next year,.... I'll primarily set up to take a 2 second exposure and try to improve my timing on squeezing the shutter.
This was the only other 2 second exposure. Not as good but much better than the lot that exposed in less than 1/2 second. The 2 second delay adds the detail that there was a stiff North wind blowing the fireworks to the left, over Rockport Harbor.