The high ISO capability of today’s new camera models is a true game changer. It opens up a range of light previously unexplored in the history of photography. Fearing noise, many people unnecessarily limit themselves to the lowest ISO setting and never explore this incredible range of light with all of its unique qualities—and surprises. (Don’t fear noise. Instead, read my series of articles.) Try night photography, and you’ll quickly realize the camera eye now can show you more than the eye can see. There have been many times now when I make exposures just to see what’s out there. Practice the art of night photography, and you’ll learn to see in new ways.
What settings should you use when making exposures in low light or at night? Use a tripod and cable release, set ISO to 800 (or higher), open up to ƒ/5.6 or wider, focus at infinity, and keep exposures below 20 seconds. While this is a good starting point, that’s all it is, as you’ll need to modify settings based on the specific light(s) in a location, the equipment you’re using and the effect you want to produce. Instead, ask yourself what concerns do you need to be mindful of, and what points of control do you have when making low-light or night photographs? Develop your sensitivity to these factors, and you’ll know why and when to improvise and even what more you can explore. These tips will give you a solid foundation from which to begin your explorations in low-light and night photography.
1. Use A Tripod. Tripods are essential for long exposure techniques. The tripod head you use is at least as important. It pays to invest in good gear. Remember, the best gear is not only dependable, but also easy to use. That said, when you don’t have to use a long exposure (longer than 1/60th of a second) or are exploring camera motion (be bold), you don’t have to use a tripod.
2. Use A Cable Release Or An Intervalometer. Minimize camera motion by using a cable release to make exposures. In a pinch, you can use the self-timer mode to delay exposure at least two seconds after you touch the shutter release. Once you’ve composed an image, touch the camera setup as little as possible. If you’re stacking multiple exposures to create star trails, use an intervalometer to automate timed exposure sequences.
3. Use Bulb Mode. Bulb exposure mode is the only mode you can use to make very long exposures. Most other camera modes won’t exceed 30 seconds.
4. Use Mirror Lock-Up. Further reduce motion blur by using the mirror lock-up function on your camera. Alternately, increase exposure for two seconds and block the lens for that time period. When you’re shooting on a tripod, don’t use image stabilization; it will reduce rather than increase sharpness.
5. Use A Good Fast Lens. Fast lenses reduce exposure times. Each ƒ-stop offers twice the amount of light as the previous one, which translates into an exposure that lasts half as long (reducing motion artifacts) or one lower ISO rating (reducing noise). If you can, pick up the speed you need with high ISO (without noise becoming unacceptable) and higher apertures. The sharpest aperture on most lenses is typically either ƒ/8 or ƒ/11. Confirm this with an individual lens by testing it, preferably before making exposures at night.
High-quality lenses reduce artifacts like chromatic aberration (color fringing easily corrected in postprocessing) and sometimes coma aberration (distortion that’s impossible to correct without substantial retouching).
6. Reduce Star Trails With Short Exposure Times—Or Go For Broke. The duration of exposure with apparent lack of star trails varies based on focal length. Essentially, star trails become apparent less quickly with wider-angle lenses. Here’s the equation for calculating how much trailing occurs when using a fixed tripod: TL (trail length) = FL (focal length) x E (exposure time)x 0.00007. As some trailing always occurs, make a series of timed exposure tests and examine the files closely to determine maximum exposure times that deliver acceptable results.
If you want to produce star trails, anticipate making very long exposures and quite possibly stacking multiple exposures for the final result. There’s an art to this, which requires its own article.
7. Find The Infinity Focus Point. Achieving critical focus in the dark can be challenging. Some cameras can point focus on a bright star when the moon isn’t visible. You can set focus to infinity before nightfall. Unless you know you can rely on them, don’t trust the markings on your lens. Set focus at infinity with autofocus. Once set, you can turn off autofocus and tape down your lens; it’s easy to bump your lens in the night. If the temperature of your lens changes dramatically, you’ll need to refocus. When not focusing on infinity, use a flashlight or high-powered laser pointer to illuminate objects to focus on, focus, then immediately turn off autofocus.
8. Use High ISO. How high can you go? It depends on your camera model—invest in a newer one, as monumental advances have been made in the last few years—and your tolerance for noise. Don’t listen to that little voice in your head or any one else who says, "You can’t…." Instead, try it and find out what happens. Systematically test your camera to find the upper limits when noise becomes unacceptable to you. Make a series of equally dark exposures at different ISOs, process these files without noise reduction, and comparing them at 100% screen magnification, critically evaluate noise levels in both detailed and smooth image areas. Only this kind of scientific testing will be able to prove to you how high you can go. You’ll find this will be an hour or two that’s well spent. At the end of it, you may even say, "Eureka!"
9. Check Histograms. Monitor histograms after every exposure. An exposure’s histogram will tell you if the shadow or highlight detail has been lost, if underexposure is likely to produce noise, and if you need to make multiple exposures. Remember, data in the lower half of the histogram gets noisier the closer it gets to the black point, so avoid underexposure. Often, when you weight your histograms to the right for low-light exposures, the images will look like they were shot by daylight and will need to be processed to darken them appropriately; you’ll get higher-quality data this way.
Is it better to bury the histogram and use a high ISO? Or is it better to use a high ISO and expose to the right? Strike a balance. Both an underexposure and a high ISO produce noise. Avoid the extremes in both. Be mindful; you may only be concerned with the histogram for one part of an image.
10. Consider HDR Techniques. You’ll want to bracket exposures more frequently than you may think. You may only use additional exposures for one part of an image, i.e., one exposure for the foreground, one exposure for the sky and one exposure for the moon. There’s a progression of HDR techniques that will help you with a majority of your exposures, not just your low-light photography. (Read my series of articles on HDR resources a>.) 11. Use Camera Exposure Noise Reduction Sparingly. In-camera long-exposure noise reduction works by taking a second exposure of the same length with the shutter closed to map fixed sensor noise and then remove it from the first exposure. This is particularly useful with longer exposures when sensor noise becomes most pronounced. But doubling exposure times for every exposure may not always be advantageous, especially with shorter exposures at lower ISOs when noise is less pronounced. Furthermore, you can often reduce noise equally well with software during postproduction, so learn how and when to turn this camera function on and off.
12. Master Noise-Reduction Postprocessing. Learn what kind of noise and how much of it can be removed in postprocessing, and you can comfortably use even higher ISO settings. These are essential skills. See my collection of noise-reduction resources at johnpaulcaponigro.com/lessons/technique/.
13. Consider Adding An Artificial Light Source. You don’t have to be in the dark to prepare to make exposures in the dark. At a minimum, bring a small flashlight to help you check camera settings and find equipment. Many people like to use red light sources, as they help your eyes readjust to the darkness much more quickly.
In addition, consider using portable flash units or a strong flashlight for light-painting techniques; light up an existing visual element or add a new one with the light itself. You can blend multiple exposures, with and without artificial light sources, to control where to introduce light into a composition, and how much.
14. Test. Before you shoot, test, test, and retest. Test what you can ahead of time. Familiarize yourself with camera functions, find infinity focus, identify acceptable ISO, including postprocessing, know at what exposure times you can expect motion artifacts like star trails, etc. The last time and place you want to be testing your equipment is while you’re trying to make finished exposures in exciting locations. Practice finding camera controls in the dark. Light up your camera’s LCD, activate your camera’s level, turn on and off autofocus, activate your camera’s image review, and switch between image and info. If you don’t practice in the dark, when you get on-site, you’ll feel like you’re all thumbs. Testing ahead of time will greatly reduce, but not entirely eliminate, on-site testing. To optimize your exposures for each unique situation, you’ll need to make minor modifications to the general practices you’ve previously established.
On-site, you’ll most likely want to make two types of test shots. First, make a test shot at exceptionally high ISO to confirm composition—and possibly focus. Second, make a test shot at acceptable ISO to confirm optimum exposure—if you’re lucky, this may be your final exposure, but quite often you’ll find you need to make a slight modification to that exposure or a second or even third bracketed exposure to enhance the first. Optionally, you may want to test what motion artifacts are introduced by extended exposures and if they’re pleasing.
When you start practicing high-ISO photography, you’ll begin to see many more possibilities for making images. You’ll soon discover yourself savoring the many qualities of light long before and long after sunset. There’s so much waiting to be discovered in low-light and night photography, so go explore it! And use these tips to help guide your explorations.
John Paul Caponigro, author of Adobe Photoshop Master Class and the DVD series R/Evolution, is an internationally renowned fine artist, an authority on digital printing, and a respected lecturer and workshop leader. Get PDFs and his enews Insights free at johnpaulcaponigro.com.