Long-exposure photography involves leaving your camera shutter open for an extended period to introduce motion blur. It can be used to show the constant movement of elements around you, from clouds gliding in the sky to a running waterfall to waves crashing on the rugged coast.
Decreasing your shutter speed is the key to capturing motion blur. Generally, anything under 1/30 of a second will introduce some motion blur. However, since the shutter is opened longer, we are introducing two problems.
First, we need to control how much light hits the sensor to get the proper exposure by lowering our ISO and closing the aperture. Smartphones have lenses with a fixed aperture, so you must use an ND filter or an app capable of merging several shots to mimic motion blur, such as the Moment App.
Secondly, lower shutter speeds will capture any shake while holding your phone, so a tripod is needed to keep our images the sharpest.
There are several ways of capturing long exposures with your iPhone, and while they can produce similar results, the shooting experience and what you'll need will differ.
With the help of accessories like Neutral Density (ND) filters and a tripod, you can shoot long exposures on your iPhone the same way you would on a DSLR/mirrorless camera. ND filters help block some of the light hitting your sensor. They come in many different densities (2 stops, 4 stops, 8 stops, etc.)
I like to use VND with the iPhone as I can quickly decrease or increase the amount of light. A stronger VND is better for capturing motion blur in a bright environment. The Moment VND 6-8 stops filter is a good choice.
You'll need an adapter to mount the filter onto your iPhone. The simplest way is with the Moment 67mm Filter Mount.
Next is a tripod to keep your iPhone steady, and a phone clamp such as the Moment Tripod Phone Clamp with Cold Shoe Mount is a good choice as it can be used with different phone cases.
Finally, you need an app that gives you complete manual control over your camera's settings. The Moment Pro app is perfect and filled with beautiful features we'll use through this guide.
Now that we have all the accessories, it's time to head out and shoot!
Once you find the subject you want to capture, set down your tripod, mount your VND filter onto your phone, and open the Moment App. Choose the standard photo mode.
For this method, we will shoot in RAW. You can choose either standard RAW or ProRaw if it's available. To change the format, click on the top banner to change the format. By default, it is set to HEIF or JPEG.
Frame your subject and lock your tripod to keep everything steady. Set your iso and shutter to the lowest available, generally ISO 34, and shutter speed at 1 second. Unfortunately, Apple doesn't let us use a shutter speed of less than a second. You may also find the interface slow. At this point, use the VND to compensate for the light until you get the correct exposure while keeping an eye on your histogram. (To activate the histogram, navigate to the settings, and under "exposure and focus," switch on the histogram.
Finally, use the timer option to delay the shutter by a few seconds. This will ensure you don't introduce vibrations in the iPhone while pressing the shutter. A three-second delay is enough.
The second method to caption long exposures uses a feature available inside the Moment Pro app. Click on the camera icon to reveal the different capture modes, and choose "slow shutter." By default, it is set to "light trails". Switch to "motion blur" and choose a speed setting (0.5 - 1 - 2 - 4 - 8 - 15 - 30 - Bulb.) These settings mimic the shutter speed you would set on a DSLR; the longer, the more motion blur it will capture — experience with different speed settings to create desired effects. If you choose bulb mode, you manually decide when to stop the capturing process by pressing the shutter.
Although not required, you'll get better results when using a tripod.
Keep your iso at the lowest available for sharper images. In low-light situations, you can decrease your shutter speed (independent of the motion blur settings). In bright conditions, you can use your VND filters also to keep your shutter speed at a slow value.
Are you shooting water? Try a polarizer filter (CPL). It will cut the reflections and allow you to see what's below the water while rendering the colors punchier and the overall image more dramatic.
Try this mode with Moment lenses. I particularly like the Anamorphic lens to capture more expansive photographs. Plus, in the Moment App, you can set it to an Anamorphic lens to see exactly how it will look, and the de-squeeze will be automatically baked inside your image, so there is no need for Photoshop!
Did you know images you shot as "Live Photos" in the default camera app have several built-in effects? One of them is long exposure. Once you've shot an image, navigate to your photo library and click "live" in the top left corner. Choose long exposure and wait a few seconds. Tadaa! It's the easiest way to shoot motion blur on your iPhone. This will also work on past photos you may have shot, so check your photo library for waterfalls and rivers and try the long exposure effect.
Long-exposure photography can be daunting, but the more you practice, the easier it will become. Feel free to experiment with different settings, lenses, and filters, whether the built-in lenses on your iPhone or the Moment lenses.
My favorite method is using the built-in "slow shutter" features inside the Moment app. It creates the best results and still allows me to use manual settings.
