Walking with a friend in the dark is better than walking alone in the light. Helen Keller
There’s a huge number of things you can do to make your event photography look a little better. You can:
1. Get a better camera
2. Get a better lens
3. Grow resentful of the fact that I suggest you get better equipment and stop reading this article
4. Use a rear curtain sync on your flash to match ambient.
Photos used in marketing and advertisements almost universally never involve a subject that that was clearly lit with a flash on an almost pitch black background. There’s something about the artificiality, no matter how good the image, that makes people choose otherwise.
In a super dark space, you can’t really do much about it and if there’s no light to pick up, there’s no light to pick up and you really can’t force the matter. You can boost your iso to some ridiculous level and lower your shutter speed to a 50th of a second and hope for the best, but otherwise your options remain limited.
That being said, this is where your flash curtain comes in. There are a few different flash modes, none of which I really ever use other than rear curtain (which I find infinitely helpful). All a rear curtain sync does is sync the flash pulse from your speedlight to the end of the shutter-click, rather than the front. If the flash is set to 1/200th of a second, this isn’t really going to matter, but if you keep the flash down at around 1/20th of a second, you’ll draw in enough light to expose for ambient. Because your speedlight popped at the end of the sync, rather than the beginning, your subject won’t experience any shutter-drag, and your image won’t automatically look like a photo of someone with a really bright light in the middle of a lonely galaxy with no star.