Long Exposure Photography: What You Need To Know To Take Stunning photos

Have you ever fancied trying something new to spice up your photography and give your pictures a new slant?  Why not try some long exposures?  If you’ve ever seen pictures with silky water or streaky cloudscapes most likely they were taken using a long exposure.  It isn’t difficult to do and doesn’t even necessarily require lots of expensive equipment.  Why not have a go?  You can have huge fun with long exposures, discovering effects you will never see with the naked eye.

Long exposure shot of a waterfall
The milky effect of this waterfall is made possibly by using a long exposure.

What is a long exposure?

Basically, it’s any photo where your exposure time is longer than a second or two.  Sometimes a couple of seconds is sufficient to create the effect you’re after, but you could have your shutter open for minutes, or even hours.

Subjects for long exposure photography

Long exposures have uses in many different genres of photography – here are just a few scenarios where you might want to experiment with them…

1. Landscapes

Use a long exposure to blur the movement of clouds across the sky  or the movement of plants and trees within the landscape.  If you like the idea of blurring the clouds look out for days with broken cloud and a fair amount of wind. Try opening your shutter for between thirty seconds and a couple of minutes and you’ll see the clouds turn to streaks across the sky as they move.

Using a ten stop ND filter has lengthened the exposure time enough for the foliage of this tree to blur in the wind. Photo by Helen Hooker

2. Seascapes, Rivers, and Waterfalls

We’re used to seeing water as crashing waves or falling droplets but long exposures can create beautiful silky effects.  By slowing things down, fast moving water turns into something much more peaceful.  Seascapes can turn into minimalist scenes of tranquility, while raging waterfalls can appear as whisps of cotton candy.  An exposure of a second or two will soften a fast moving river enough to create a different texture. A much longer exposure will completely soften water to create that unique silky look.

Long exposure of a seascape at broad day light.
Long exposure of a seascape at broad daylight.

3. Cityscapes

You can blur the movement of clouds across a cityscape but there are other uses too.  One of my favorites is to blur the movement of people, sometimes removing them from my images entirely.  This can be really handy in busy tourist spots where, no matter how long you wait, you will struggle to capture a clear shot.  Sometimes you’ll be left with some translucent ‘ghosts’ in the scene as people walk around. This can add a wonderful sense of movement to your images without being intrusive.

London’s Millennium Bridge at rush hour. You’d never know the bridge was full of people when I took this! There’s just one solitary figure at the bottom of the path, who stood there for the whole of my thirty second exposure. Photo by Helen Hooker

4. Light trails

There are plenty of other uses for long exposures, especially in the dark.  What appears to our eyes as a single light source becomes a light trail when you leave the shutter open for longer.  If you can find a suitable vantage point, it’s fun to photograph the trails created by passing traffic.  Try to find a spot where you can create some shape from these trails. For example, a bend in the road or a nearby landmark. These can add a lot to your composition.  Since you will be shooting at night, you won’t need any expensive filters so it’s a great way to begin experimenting with long exposures.

Light trails photography over a bridge
Light trails photography over a bridge

5. Star trails

Of course, nature provides its own light sources – the myriad of stars above our heads.  Although the stars appear as pinpoints of light to our eyes, they turn into lines when you shoot at slower shutter speeds, as the earth rotates in the sky.  To capture this effect, pick a clear night, aim your camera towards the north star and leave the shutter open for a period of several minutes.  You will find the stars form circular trails around the north star.  You can leave your shutter open for an hour to capture a complete circuit of the stars, or even for as long as the battery power lasts.

The only downside of this method is the risk of increased noise in your images as your camera sensor heats up.  One trick to avoid this is to shoot a series of shorter exposures and composite them into one image later.

Following image is created by stacking together few forty-second exposures to create star trails in the sky.   If you’re not confident with Photoshop, fear not, as there’s a free app available from www.startrails.de to stack your images. It’s very easy to use.

Star trails above a country church.
Photo by Helen Hooker

6. Light painting

If you really want to challenge yourself why not try a little light painting?  If the weather’s bad outside you can even try this indoors.  All you need is a light source – perhaps a torch or some coloured glowsticks – and some creativity.   Set your camera up on a tripod in a dark space, open the shutter for a minute and go to town, literally drawing with the light.  As long as you keep moving your body won’t register on the camera’s sensor but every movement of your light source will.  If you want some inspiration do take a look at Andrew Whyte’s website.  Andrew specializes in this sort of photography and his level of creativity is amazing!

One of my attempts at light painting – using a combination of flash and a light wand.
Photo by Helen Hooker

What gear do I need for Long Exposure? 

For some of the techniques, you may not need all of this equipment. However, they can help you to avoid camera shake, as well as extend your exposure times.

1. A sturdy tripod

If you’re planning to shoot exposures running into several seconds you’ll need a means of supporting your camera.  The obvious choice is a tripod, preferably the sturdier the better.  However, if your tripod is a little flimsy you can always add extra weight. Add a bag of stones on the base or even just hang your camera bag underneath it.

2. What if you don’t own a tripod?

All is not lost!  I sometimes use a beanbag as a camera support.  If you can find a solid surface, overlooking your subject, you can successfully bed your camera down onto on a beanbag. This will create as much stability as you would have with a tripod. This approach may constrain your composition but it’s useful to keep a small beanbag handy for unexpected opportunities when you don’t have a tripod with you.

3. Neutral density filters

If you’re planning to shoot long exposures in daylight you will need one more piece of gear – a neutral density (ND) filter.

ND filters basically act as sunglasses for your camera, cutting out some of the light before it reaches the sensor.  They come in many different strengths.  The weakest ones will simply double your exposure time – this means a shutter speed of 1/125 of a second will become 1/60 instead.  However, as the filters get darker their light-reducing abilities increase dramatically.  One of the most popular types for this style of photography is a ten-stop ND filter (sometimes known as ND3 or 1000x). These literally increases the length of your exposure by ten stops.  This means that 1/125 shutter speed will become an exposure of eight seconds.  You can buy more extreme filters too, such as the Lee super stopper.  This little baby will add fifteen stops to your shutter speed, turning a two-second exposure into over seventeen hours!

At nearly two minutes, the long exposure has completely blurred the water in this beautiful seascape. Photo by Ram Ya

How to calculate exposure time with an ND Filter?

Well, you could calculate it in your head, doubling the length of exposure for each stop of your filter. That means doubling it ten times for a ten stop filter.

However, unless you’re very good at maths, that will take up lots of valuable photography time!  Instead, I would suggest you download an ND calculator app for your smartphone.  There are lots available for free and it’s much quicker.  If you don’t have a smartphone there are charts available online.  Why not do a quick Google search for ‘ND filter exposure calculator’ and print one out to keep in your camera bag?

What type of ND filter should I buy?

There are two main types of filter available – square ones and round ones.  If you already have a square filter system, perhaps for a polarizer or graduated ND filter, it makes sense to follow the same route for your ND filter.  These systems generally have a filter holder that attaches to the front of your lens. You can slide the various filters into the grooves to block out the light.

The alternative is to buy a round, threaded filter that screws into the front element of your lens.  These are really compact and easy to store but can get pricey if you have several lenses with different size filter threads.  My solution to this is to buy a filter to fit the biggest lens you own, along with some step-down rings so you can attach it to smaller lenses as well.  The step-down rings can be bought very cheaply on eBay and the overall cost will be much less than buying several different size filters.

Are there cheaper alternatives?

Now to the thorny issue of cost…  You can spend a huge amount on high-quality ND filters.  For instance, the Lee Big Stopper square ten stop filter costs £99 in the UK, with a B+W 77mm circular one is currently priced at £150.

So, are there options for those who just want to dip their toe into the world of slow photography?

Absolutely!  A quick check on eBay brings up 77mm filters by cheaper manufacturers in the £30-40 price range.  While these may not be quite as high quality as the Lee and B+W filters, they will work just fine and allow you to see if you enjoy this genre of photography.

A raging river in Cumbria. Using a six stop ND filter gave me an exposure time of two seconds, which slowed the racing water and softened the surface of the river. Photo by Helen Hooker

Focusing with an ND filter

There are a few but they’re easy enough to get around.  The most obvious one is how to focus through an extreme ND filter.

If you hold a ten stop filter up to the light, you will see almost nothing through it and this creates a problem for your camera if you wish to use autofocus.  One solution is to compose and focus your picture, then switch your lens to manual focus mode before carefully applying the filter.

This can be tricky as you need to take care not to move the focus or zoom rings while putting your filter on.  Alternatively, most cameras with live view will be able to focus with the filter already in place.  This tends to be my choice of technique, especially when I’m out in the landscape, often in less than ideal weather!

How to avoid Color cast issues with ND filters

Another issue with many extreme ND filters is one of color casts.

Even with a high-quality filter, it will often affect the white balance you set, no matter how careful you are. The B+W filter I use with my DSLR adds a slight magenta hue to my photos.  The solution here is to shoot in RAW rather than JPG mode as you can adjust any color cast in Lightroom or Photoshop afterwards.

Of course, if you intend to convert your images to black and white it doesn’t matter at all!

Don’t forget to compose your image carefully!

It’s very easy to get caught up in the excitement of doing something new and forget to really take care with your compositions.  While long exposures can be exciting to create, you’ll appreciate the effort even more if your pictures are well composed too.  It’s always a good idea to take a few test shots without any filters first, to check you’re happy with your composition.

If you’re shooting exposures that stretch into several minutes you’ll save a lot of time this way too!

The curvaceous light trails on this road lead the eye to the City of London in the distance Photo by Helen Hooker

Tips for getting best Long Exposure shots

1. Use Bulb mode

On most cameras, the longest shutter speed you can specify is thirty seconds.  If you’re shooting a longer exposure then this will need to set your camera on BULB mode.  This setting allows you to keep the shutter open as long as you like – or until the battery runs out if you’re being really extreme!  Most DSLR cameras have a Bulb or B mode on the exposure dial but you may have to hunt for it in a menu or manual mode on smaller mirrorless cameras.

2. Use a remote release

Having found bulb mode, set up your shot, focus and apply your filter.  Then open the shutter using your remote release and close it again when your exposure time is up.  You can keep track of the length of exposure using a watch or the timer on your mobile phone.  Without a remote, you will need to keep your finger pressed on the shutter button the whole time and that’s a recipe for camera shake!

If you’re going really long, the precise timing becomes slightly less critical than at shorter exposures.  If your exposure is several minutes the odd second over or under won’t really matter.

3. Shoot RAW

I would also strongly suggest shooting in RAW, to give you maximum flexibility in post-production.  It’s also a good idea to turn off your camera’s long exposure noise reduction (NR).  With NR enabled your camera will automatically shoot an additional frame after you’ve taken your picture.  With an exposure of a few seconds, this is mildly irritating.  If you’re shooting an exposure of several minutes it can be deeply tedious waiting for the second exposure to finish!

4. Cover your viewfinder

One other very cheap piece of kit that would be handy is some black tape to cover your viewfinder and prevent light leaks.  These aren’t too much of a problem at night but if you’re shooting in the middle of the day it could be an issue.  That said, I know of one photographer who uses a black hat to cover their camera instead!

When can I shoot long exposures?

The short answer is, Anytime!

1. Daytime with an ND filter

If you have an ND filter, you can get long exposure shots anytime you like!

2. Daytime without an ND filter

If you want to give this a go without buying any filters, try reducing the size of your aperture (use a higher f-stop number) while keeping your ISO setting as low as possible.  This combination can quite easily bring you into exposures that are several seconds long.

One word of warning, though, try to avoid using really small apertures (f22 for instance) as you will then start to see a reduction in sharpness in your images due to diffraction.   However, there’s no harm in trying this out in any case, even if it’s just to see if you like the results and want to experiment further!

3. At night with or without an ND filter

If you’re shooting in low light or at night time you may well find your shutter speeds are already getting slower. So you can attempt this without an ND filter at night. Just remember that you can get reduce exposure time with smaller apertures and lower ISO settings. If you do have an ND filter, you can further increase the exposure times.

So there you have it – lots of ways you can exploit the slower side of photography. 

Why not give it a try.  Pick one of the techniques I’ve talked about and see where it takes you – you might find it unlocks creativity you never knew you had!  If you’ve enjoyed this article please do share it with your friends on social media.  While you’re at it, why not share the results of your long exposure experiments in the comments here – I’d love to see them!