Mastering Long Exposure Photography
The general consensus is that a long exposure photography begins with a shutter speed of about a 1/30th of a second. This is the point at which, for most camera/lens combinations, that you can no longer handhold your camera without seeing motion in your capture. Like with everything, there are exceptions to this rule. I have successfully shot handheld at exposures as long as 1 second with the Canon 16-35mm f/4L IS lens, for example.
Here are tips to get you started with long exposure photography, which is an essential skill for beginners to master. It gives you creative freedom and teaches you how to handle unexpected low-light conditions.
Tools Needed for Long Exposure Photography
A tripod is a must for long exposures. I have invested as much in my tripod as I have in some lenses! A well-built tripod is worth its weight in gold (and, like with backpacking equipment, the more you spend the less weight you have to deal with). A good tripod will last your entire career. I prefer carbon fiber models for their lightness and durability. Learn more about how to choose the right tripod for you in The 9 Best Tripods for DSLR Cameras in 2018.
You can’t just stop at a tripod, however. A good tripod is only as good as the head you attach to it. For ease and speed of adjustment, I use a ball head. Ball heads use a ball and socket mechanism that allows fast adjustment in all directions. The ball head is closely related to the grip action-style head. There are also pan/tilt heads, fluid heads (essential for videographers), and gimbal heads (ideal for very large lenses).
A great companion for long exposures is a locking cable release. This allows for timed exposures longer than 30 seconds and you can find one for just about any camera on the market. The best ones have a lock that slides over the shutter button, allowing you to keep the shutter open as long as you desire without having to stand there and hold it. For this, set your camera to BULB on the shutter dial (or in your shutter menu). Time your exposure with a simple watch or timer on your phone. Newer mirrorless cameras have shutter speeds longer than 30 seconds built-in. This allows you to shoot longer exposures without relying so heavily on a cable release.
Image Quality and Long Exposures
Long exposures introduce more noise into a photo. If you shoot RAW, you will have more editing capability to remove that noise. You can shoot JPEG if you are willing to convert that JPEG immediately after import into something more editable, like a TIFF or DNG, but a JPEG will still be harder to work with in post as your exposure times increase. This happens because the sensor is receiving power while it is exposing and that power heats the sensor up. A hot sensor is less effective at producing a clean image.
You can counteract this heating effect by turning on your long exposure noise reduction from within your camera’s menu settings. This functionality will double your listed exposure time, so a little patience is needed. For example, a 30 second exposure with “long exposure noise reduction” turned on will take about a minute to generate. This is because your camera creates an all-black exposure which you don’t see but that the camera processor can use to find and delete noise.
Knowing Your Subject
Subject, subject, subject. If you know what your subject is when you take the photo, your viewer will pick up on that thought when they look at your work. When mastering long exposures, subject is even more important. You need to find a balance between what is moving and what is still in your photo. If your viewers don’t understand your subject, they move on. If they move on, they forget who created the photo. Every rule is meant to be broken, though. The entire photo can be in motion if you are going for a total abstraction of the scene in front of you.
The Reciprocal Relationship of Your Camera Settings
Remember your three camera settings: aperture, shutter and ISO. They are reciprocals of each other (sometimes referred to as the “exposure triangle”). This means that you cannot change one without it affecting one or both of the other two. What happens if you don’t make an adjustment to shutter or ISO when adjusting aperture? You get an overexposed or underexposed photograph.
There are times when shooting long exposures that the ambient light is too bright to capture the motion that you want to illustrate. In this situation, your ISO might be at its lowest setting and your aperture closed down as small as possible (f/22-f/32) but the shutter speed that allows for a decent exposure is simply too high to effectively show motion.
You can fix this with a Neutral Density Filter. This filter is neutral in color and darker in density. Attaching one to your lens will give you that added darkness so that you can slow your shutter way down without overexposure. My favorite filters are from Breakthrough Photography. Breakthrough produces their Neutral Density Filters in 3, 6, 10, and 15-stop increments. A 15-stop filter will remove 15 stops of light from your photo! This will effectively allow you to shoot blurred motion with super slow shutter speeds in high-noon light!
In addition to (or in place of) a Neutral Density Filter, you can use a Polarizing Filter in a pinch. A polarizer typically loses 2-stops of light. It’s not nearly as much as a calculated Neutral Density Filter but it can help slow things down a little.
When playing with these settings, you’re going to have to take some test shots which means “chimping” (constantly reviewing your image). Take a test shot or two and select the shutter speed that makes you feel good. See what happens! By making test shots along the way, you will begin to learn what shutter speeds allow you to produce the long exposure effect you really want.
Forget the Tripod
Wait, what? The very first thing in this article is about how important tripods are! Well, this is where rules get broken. This is the time to discuss panning along moving subjects – or even moving your camera long still subjects for abstract results. This is giving yourself pure freedom and creativity. My secret shutter speed for doing this and getting cool effects is 1/8th of a second. Of course, that varies depending of your subject’s speed. But start there and see what you like and are able to capture.
Digital photography has opened the doors for experimentation. You no longer have to wait weeks for those probably-mislabeled rolls of film to return before realizing you blew it. While mastering long exposure takes a little forethought, with a digital camera in-hand you will walk away with another creative way of looking at the motion of our world. The most important tip of all is to have fun!