I've recently shot the following photo (f/8, 4.0 s., ISO 100):
In post-processing, it appeared that:
The magenta channel was practically blown out, and I had a choice to either reduce/desaturate the purple and magenta parts (which is not the intention of the shot), or lose the details,
The details of the “light trees” are completely lost. Here's a zoom on a relevant part of the photo:
I imagine that in order to get the trees right, I should set a faster shutter speed, but then, the overall scene will be too dark. The current histogram (after post-processing) looks like this:
and on the original image, there are even more dark zones.
As I understand it, using bracketing in order to darken the trees only won't work either, since it will produce dark borders around the trees.
What are my options if I have an opportunity to redo the shot?
I had no opportunity to redo the shot, but I reproduced a similar lighting situation at home with a LED emitter. Indeed, the suggestion by MirekE gives if not an ideal, at least much better result than a single photo. Those are the three photos produced through bracketing:
1/5 s.: the whites are blown out, and dark zones are barely visible.
1/20 s.: the whites are nearly correct, but practically everything else is invisible.
1 s.: the details in the dark are visible, but the lights are appearing just as a glowing white zone.
An HDR of those images in Photoshop gives this the following image. It doesn't look very natural, but is still much better than any of the three previous photos taken individually.
Of course, an HDR of a scene where people are constantly moving in front of the light sources could provide additional difficulties, but probably multiple series of HDR shots could produce a decent result.