Imagine yourself in the middle of nowhere, before sunrise, there’s a quiet around you, the stars start to fade and the light of the sun begins to bring everything to life in blue hues. There’s a magical moment that happens in between day and night. Light gets softer and the glow of the sun still affects the landscape in a beautiful way. Most people underestimate this time of day, forever chasing golden hour and the colors against the clouds as the sun sets, but this has easily become my favorite time of day to photograph. I’ve become obsessed with twilight scenes and have learned to capture them using a multiple-exposure technique known as blue hour blending.
I’m often on a road trip to anywhere I can get to, trying to explore new landscapes and potential foregrounds. Blue hour affects many scenes differently, and it’s become an interesting challenge to creatively capture these places during a time of day that is often forgotten. Blue hour light is never the same in two places—areas like sand dune fields, salt lake playas, and snow-covered lakes tend to reflect light more than the rock formations of the high desert. This is why I encourage each one of you to get out there and experience these changes in real time.
Here are a few steps to get started with blue hour blends.
Why Photograph during Blue Hour?
The reason for creating a blue hour blend is, first and foremost, to be able to capture the foreground with a higher aperture and lower ISO, to keep all the detail intact with as little noise as possible. This will also allow you to have more control over the light in your photograph—there are no harsh shadows or blown-out highlights in a blue hour shot. The light will be pretty even throughout, allowing you to adjust better in post-processing.
Photographing during blue hour also allows you to play with motion more than you could at a different time of night and also in a way that won’t affect the stars in your image. If you are photographing a beach scene, for example, this lets you play with longer shutter speeds to create that dream-like movement in the water. Or if you wanted to introduce light trails into your scene, you could use the longer exposure to achieve this look and still be able to capture the rest of the landscape around those light trails.
Have a Plan
When shooting for a blue hour blend, the first thing to keep in mind is the resulting image. Unlike shooting a single frame, you have to be able to imagine what this shot will become and then capture all the elements needed to put it together. With a single frame, you can physically see the result; however, with a blend you will have to start with a plan.
Consider whether you are photographing a twilight scene or a Milky Way scene. If you are photographing blue hour for a Milky Way scene, you need to be able to predict the position of the Milky Way. You will also want to leave more room at the top of your frame for the Milky Way while composing. If shooting for a twilight scene, you can leave less room at the top of the composition for stars, and the foreground can fill more of your frame. You will also want to take your star shots earlier than you would if you were photographing the Milky Way.
Secondly, think about your foreground. Does the place you are photographing lend itself better to a sunrise blue hour or sunset blue hour? Since you are using the light of the sun as your “light painting,” it’s important to know what direction and angle that light will be hitting your foreground subject. A good example of this is the Eastern Sierras. We visited the Alabama hills on our road trip to NAB. This place has fantastical rock formations, endless cacti, and a view of some spectacular mountain peaks. When shooting blue hour in this location, it is preferable to photograph blue hour just before sunrise, because the light will fall on the peaks in the most beautiful way. If you photograph a sunset blue hour here, the mountain peaks lose their definition because the sun sets behind the mountains, and that loss of light results in less dimension.
Start with the Right Settings
I’ve found that there are certain settings with which I always start. These can, of course, be adjusted to suit a scene better. I like to use an aperture of f/11 to get maximum depth of field, without destroying the quality of the image. Next, an ISO of 100—keep the ISO low to reduce noise. Finally, I wait for the light to be low enough to reach a shutter speed of 30 seconds. I find the light to be the best at this shutter speed. I also find that a cooler white balance helps with blending later, in post-processing.
A few things can change these settings and it’s important to note what they might be, especially if you are shooting something with a slight movement, such as a flower or human element. Even with little to no wind, subjects like these tend to move more, so to counteract that, you will need a faster shutter speed, which means either changing your aperture or ISO to accommodate for the reduced amount of light.
Photographing Stars with Blue Hour in Mind (Stacking Stars for Noise Reduction)
Since you are photographing the foreground with low noise at blue hour, it’s important to carry that trend through to your star frames. You will want to find a way to photograph the stars with as little noise as possible, and this will create a more convincing blend. Instead of shooting a single frame for the stars at ISO 3200, consider shooting multiple frames at a much higher ISO and stacking these with software such as Starry Landscape Stacker, to reduce noise. This will capture more light, detail, and color of the stars, and the stacking reduces the noise almost completely.
I use an aperture of f/2.8 at ISO 10000-12800, and a shutter speed that will vary based on focal length—generally 8 to 15 seconds. By using these settings as a base point, I am allowing as much light as I can into the camera and still getting pinpoint stars free of trailing. Unfortunately, these settings result in high noise, but by stacking 15 or more shots together, I end up with a final image with little to no noise. This lends itself to a blend with a blue hour foreground much better than a single shot with some noise could.
Putting it All Together
There are several ways to put the shots together. I use Photoshop to get the results I want. I start by doing slight edits in Lightroom, such as sharpness, contrast, white balance, exposure, etc. I bring the image into Photoshop and create a mask to remove the sky from my foreground image. Finally, I bring in my stacked sky image and start adjusting basic elements on both layers to match them together, like exposure or white balance.
This technique of photographing the night sky may seem daunting; however, this is your chance to create using all the tools from your camera and post-processing. I encourage you to play and see what fits your needs and personal taste. Experiment with settings and post-processing techniques to find a balance that works perfectly for your artistic vision. Blue hour shooting is such a great way to express your view of the world, and come up with a result that is uniquely your own.
Jess Santos is an adventurer and photographer with a specialty in astro and night photography. Santos is a member of the Sony Alpha Imaging Collective and you can find more of her work on her Instagram page.