How to make great images after dark

Night photography can be quite a challenge. After all, you're chasing light that's barely there, and you have to work your camera in the dark. 

You can solve the latter problem with a flashlight, but you need skills to handle the photographic hurdles. Keep reading for a breakdown of equipment and techniques that will help you conquer three popular night photography scenarios: mixing ambient with flash, photographing fireworks and capturing star trails.

Whether you're working with a point-and-shoot or a DSLR, the first ingredient for night photography is manual control. You don't need to be a master of exposure, but you should have a camera that allows you to adjust shutter speed and aperture. Use your lowest ISO (either 50 or 100), and set your camera to manual mode. Then you can begin modifying the aperture and shutter speed to create the effect you're after.

In most cases, you want to produce a deliberately long exposure, so a small aperture (such as ƒ/16, ƒ/22 or ƒ/32) will help you create shutter speeds in low light that are in excess of 5, 10 or even 30 seconds long. These long shutter speeds allow for any moving lights in your scene, like fireworks or stars, to move across the sensor and create a beautiful streak of light. 

Photographing fireworks is a rare opportunity, so it's important to make the most of your efforts. Start with a camera locked down on a tripod and a cable release, and choose a composition that allows you to photograph the fireworks-filled sky, as well as some context. Trees, buildings or people in the foreground are ideal to set the scene and provide scale. 

If at all possible, arrive early to set up while it's still light; it's easier to see your camera settings and to choose a composition. No matter how early you arrive, though, you're bound to have to make some adjustments once the show starts. Make them quickly because the beginning of the show is the best time to shoot: The sky isn't yet filled with smoke, and any residual sunset glow will provide a deep blue background. 

Start with a low ISO of 50 or 100 and an aperture in the middle range of ƒ/8, ƒ/11 or ƒ/16. Focusing at infinity ensures your fireworks are sharp, and setting the lens to manual focus stops the AF system from hunting in the dark. A smaller aperture can increase depth of field and lengthen exposures. This is good on two fronts, as more depth of field means you can ensure compositional elements are sharp, too, and longer exposures mean better motion blurs, which means better-looking fireworks. But there's a downside to longer exposures. Too many fireworks going off in a single frame can muddy a scene, so rely on experimentation verified via LCD to quickly hone in on an ideal exposure—likely somewhere from a few seconds to 10 or more to produce a good amount of blur without washing out the colors.

Photographing a person at night (or in very low light) is the one time you can break the typical night photography rules: You need a flash, but you don't need a tripod. Off-camera flash is ideal, but even a point-and-shoot with an on-camera flash will work. 

You may say, "I just use my camera's Night Portrait scene mode to make night portraits." That's fine, but knowing how to achieve that look without auto assistance will make you a more empowered photographer. And it can help you make better night portraits when Night Portrait mode falls short.

Because shutter speed changes only affect ambient light, you can control flash and ambient separately in a single exposure. Imagine you're on the Las Vegas Strip, wanting to photograph a friend against a background of bright neon. (A glowing sunset or the lights of Paris work equally well.) With your subject in relative shade (so the long ambient exposure won't illuminate them too much), you can set your camera for, say, 1⁄60 sec. at ƒ/5.6, and allow your flash's TTL metering to help create the right flash exposure. If you prefer manual flash control, start with a relatively low power of 1/8th or so. Once you've achieved the appropriate flash power to match a fairly wide aperture, you can proceed to the next step. 

With the flash illuminating the subject just right, you'll notice one glaring problem: Your background is totally black. Simply lengthen the shutter speed from 1⁄60 to 1⁄30 sec., and you'll notice it gets a bit brighter (while the subject stays the same brightness). Continue lengthening the shutter speed (1⁄15 sec., 1⁄8 sec., and so on) until you achieve a background that looks just right. With your camera on a tripod, the background will remain sharp, while handholding can create interestingly abstract blurs in the background, which is good or bad depending on how you see it. 

When you get right down to it, there's not much difference between photographing star trails and photographing fireworks. Because the Earth is rotating, you can photograph moving stars throughout the night with nothing more than a tripod, a long exposure and patience. 

The most popular way to photograph a star trail is to use your lowest ISO and smallest aperture (say, ISO 100 and ƒ/32) to allow for the longest possible exposure without building up unwanted ambient light from Earth. It really can be as simple as focusing at infinity (again, with a manual setting) and opening the shutter. 

To make things a little more interesting, consider a composition that allows for some foreground subject matter—say, tall trees entering the frame or a vantage point that allows you to shoot a landscape with stars all the way to the horizon. This requires not only an open view of the horizon, but it's also helpful if you're in a remote location without much interference from city lights. 

Pointing your camera toward the North Star will create star trails that rotate perfectly around this axis, which makes for a stunning composition. And a little flash fill added to foreground subjects is a great way to make a star-filled photograph a little extra-special. 

To make star trails, you have to allow plenty of time for those stars to transit the sky. That means exposures in the range of many minutes to several hours—or even all night long. So you want to position your camera carefully in a place where you're comfortable leaving it for the night (protected from humans, animals and the elements) that still provides for a good composition. 

There's another way to photograph stars, which is a relatively recent development. Thanks to ultra-low-noise sensors, photographers now can make short one- or two-second exposures at very high ISOs that render stars with pinpoint accuracy and show a star-filled sky in context with earthbound elements. Crank the ISO and keep the shutter speed short to make stars just as sharp as the land.