Q: What settings do I use to take outdoor photos of Christmas light displays at night?
A: It’s best to use a tripod because longer exposures will generally give you better pictures when trying to capture lights either indoors or out.
I wouldn't rely on auto scene recognition, as that will give poor results. I would also set the ISO to a low setting and use the night setting (not night portrait) for a quick shot, but if you have time to set up, use the shutter priority and set the shutter to a high value, like a second or more.
To do this, set up a tripod with a scene framed and then set to shutter priority and take some photos of the same scene without moving the camera with progressively higher shutter values. In shutter priority mode, the aperture will adjust for you. Then do the same with aperture priority. You don't have to note the settings because they will be saved with the pictures.
Make sure the type of format for the pictures is set to camera RAW - that will save all the parameters with the test photos. Then take it home and take a look at those controlled tests and from there it will be a matter of preference.
The 20 minutes or so you'll spend doing that will definitely be worth it because you'll get exactly what you want. The EXIF data in the RAW images will tell you exactly what all the settings were when the picture was taken and if you put them side by side, you can see what you prefer - longer exposures vs. shorter exposures. You may be surprised at the difference in results.
- Answer from Michael Hannigan, a Camera and Video Technician on JustAnswer