This post is about the "artillery" type of cannon, not the photographic type ...
At regular intervals throughout the year, the Fort Lytton National park fires their 64lb cannon. I've been to the "History Alive" event there for the past 2 years and tried to photograph the cannon firing, with this result from last years event (previous year I didn't take the and had lots of camera motion):
Cannon shot 2014 by John & Tracy Blackburn, on
Apart from the framing, which I aim to improve on this year, I've noticed that often with cannon shots, parts of the blast are often blown out.
Does anyone have any good suggestions on how to reduce the blown highlights on the blast without under exposing the rest of the image?