I wanted to give my top three tips for photographing cityscapes at night to make better images.
Tip #1 - Ghosting is caused when people or things in your frame move during a long exposure. It can add an interesting element to the normal image.
Note… If people or things are constantly moving and the exposure is long enough they may not appear. And if you don’t want people in your image, you can shoot multiple frames of the scene and blend them out in Photoshop.
But I like to use people moving in a photo. It gives the scene a sense of movement and interest in an otherwise boring image
Tip #2 - Always check your histogram and expose to the right. It’s easy to underexpose cityscapes at night. You look on the back of your camera and the image looks ok... then you get home and the image is too dark and noisy. Sound familiar???
One reason is your LCD screen on the back of your camera is backlit... the image shows brighter than it actually is. It is also a low res jpeg you are looking at... the RAW image on your computer is not as bright.
If you want the best result, you need the image to be a bit brighter than what you are seeing, it will give you some latitude with post-processing. Trust that most of the data is in the top 2/5ths of the histogram and you receive less digital noise if you shoot to the right. Always check your image histogram and don’t rely as much on your back screen.
This also allows you to shoot at higher ISOs
Tip #3 - Rain is one of the most challenging elements to contend with when shooting long exposures.
Water droplets on the lens are usually visible at narrow apertures, so check your lens between shots and wipe with a cloth. If using an umbrella, or cover, make sure to keep it out of the frame.
The end result when using puddles and wet ground can produce a compelling image... the reflections are awesome, the colors that illuminate the foregrounds are impactful, each offer a unique element to your night photograph.