The time from a little before until a little after sunset is a favorite of photographers everywhere. The way the light shifts to yellowy golden tones makes everything feel warmer. Hence why this time is often called the Golden Hour. The huge contrast between the relatively light sky and the dark foreground makes traditional photography challenging. After the sun is below the horizon, the light shifts to the blue end of the spectrum giving us Blue Hour. This setting is even tougher since there is only artificial light and most things are fairly dark. This is where the technique called high dynamic range (HDR) comes in very useful. Instead of taking a single exposure, with HDR we take several exposures while varying the settings to accentuate different parts of the scene specifically light and dark. Then Lightroom or Photoshop can analyze each exposure and composite the best portion of each into one master shot.
In general, camera setup for HDR is fairly simple. You need a camera with manual exposure control. For shots at sunset or where you want a longer exposure time, a tripod or other stable platform is also needed. For long exposures, either remote shutter control or self timer will also be needed. That's it.
Let's Start Shooting
Once you've got a scene picked out and have the camera setup on the tripod, take a test shot. For this example, I used ISO 50, f/16 and 1.6s exposure time. The two shots shown below do not have any processing applied in order to show the process in full.
The sky and a few lights look good. But, everything else is dark. For the next shot, I increased the exposure time to gather more light. How much to vary the settings is something that will come with experience. In this case, I wanted the river to be glassy smooth so I went with 10s. On the camera monitor preview, it looked like that might be too bright so I stopped down the aperture to f/22. In a different situation, an exposure time of 2s or 5s with no change to the aperture would have worked just as well. But, I wanted the long exposure to smooth the flowing water.
It is important to review the shots in the field before packing up. Maybe you need to take a few more shots with 2s, 3s, 5s, 1/20s, 1/60s, 1/100s ... exposure times. There is no hard and fast rule here. The bare minimum for HDR is two exposures. I'm happy with both of these so let's move on to the processing in Lightroom.
Processing in Lightroom
Load the RAW files into Lightroom. Select all of the relevant exposures, right click and go to Photo Merge-> HDR (keyboard shortcut Ctrl+H).
Leave all the boxes ticked. Depending on the scene, different amounts of deghosting may be needed. Deghosting helps if there is any movement between the exposures. As expected, there is some movement in the clouds and the river so I leave it set to Low.
The last few image specific steps involve the masking tools. These are not stricly related to HDR but I want to show the entire process. I use it to select the sky and river. For daytime shots, a slight adjustment to the blue end of the color temp can make the blue skies that much deeper and more vivid. In this scene, I experimented and adjusted the magenta-green balance towards magenta.
Crop out some grass and we're done.
Here are a few more examples from the same night. I used the sample techniques for each.
The motion of the water fountains in combination with the people wandering around was what challenging to capture. So I took four exposures with the following exposure settings:
ISO 100, f/22, 30s
ISO 100, f/6.3, 2s
ISO 100, f/3.5, 1.6s
ISO 25,600, f/3.5, 1/500s
Fairly straightforward last example. Only two exposures needed:
ISO 250, f/9.0, 1/320s
ISO 250, f/9.0, 1/60s
Still curious about HDR? Adobe has a nice explanation and basic tutorial