How to do a long exposure in photography?

If you are passionate about photography, whether traveling or in everyday life, chances are you have already heard of the term long exposure. This is one of the favorite photo techniques to capture beautiful images, especially landscape pictures. Personally very passionate about these photo techniques, I will explain in this article (mainly with a DSLR) how to do a long exposure, also called long exposure photography. If you want to learn this type of photography, for example on waterfalls, you’ve clicked on the right post!

Rest assured, you don’t need to be a professional photographer to take long exposure pictures. However, to capture beautiful long exposure photos, it will be necessary to master the basics of digital photography, at a minimum: aperture, shutter speed, ISO sensitivity (exposure triangle) and depth of field. The notions of overexposure/underexposure as well as the exposure correction of your image will also be very interesting to quickly improve on this technique. To go even further, other notions for editing your picture on an image-processing software will be necessary to understand (noise reduction, white balance, histogram, etc.). I will detail these notions in the basics of photography as I go along.

You will probably need a few tries in order to learn the technique and reflect the reality of the situation as best you can. We will see at the end of the article that a post-production control will be almost necessary for a long exposure shot. So let’s get started.

So long exposure, what is it? How does it work? What is its purpose in photography? How to do a long exposure in photography? How to capture a long exposure of a waterfall? How to improve your pictures with this technique? I will explain everything in detail.

Long exposure is a photographic technique that gives an artistic side to your pictures. Its initial purpose is to slow down or even completely blur a moving subject. These can be people, clouds, cars, waterfalls, a starry sky, a sea stream, etc.

The vast majority of photographers use this technique in landscape photography, particularly on the sea, waterfalls and clouds, three subjects that lend themselves perfectly well to this. The point is therefore to give a more original side to your picture, you could say to bring out an atmosphere in a way to your shot, thanks to a slow shutter speed of your subject.

In this article, I will explain how to achieve a long exposure in photography, what the necessary camera equipment is to apply this technique, the subjects that lend themselves perfectly to it or how to take long exposure photos according to the shooting conditions (day, night, sunset/ sunrise).

Finally, this photographic technique can in some cases be of technical interest, simply because you lack light and it is the only solution to get a sharp picture. This is often the case, for example, in night photography where the light source is almost non-existent.

Before technically explaining to you how to take a long exposure shot, a quick look at subjects where the long exposure is perfectly adapted. As explained in the introduction, to obtain an artistic effect with the long exposure technique, it is necessary to choose moving subjects (slow or fast). Here are the main popular subjects:

• The sea: it is one of the most photographed subjects in long exposure. You can modify the effect of the long exposure, which will be more or less pronounced at the seaside. You either get a slight blur of movement or a completely blurred sea (milky/vaporous effect) with a very long exposure time, sometimes several minutes. The result is much better than with a frozen, still sea.

• Rivers: another perfect subject, perfectly suited to this technique and allow beautiful artistic effects. Preferably, choose areas with more movement (eddies, next to rocks, etc.),

• Waterfalls: this is the subject on which many landscape photographers spend their time (including me). Just like the ocean, you can have more or less strong effects of the long exposure depending on the exposure time. This is typically the subject where freezing the scene will give much less beautiful results. The foggy and fluffy effect obtained with a long exposure is superb. The result will in any case be much better. Want to know more about waterfall photography?

• Clouds : the effects are particularly pronounced on clouds in rapid motion. So remember to observe the scene and take pictures at the right time. A very long exposure is often necessary to achieve this shot.

• The stars: the long exposure technique allows superb start trails with very long exposure. However, this technique requires training and good technical skills. Others enjoy taking long exposures of the Milky Way,

• Light painting: a little bit apart from traditional photography, the long exposure allows very nice effects by playing with people and light effects,

• The carousels: this is certainly not the main interest of long exposure, but like any moving subject, you can take very beautiful artistic photos of them (eg: a Ferris wheel in a fun fair). Don’t go thinking you’ll get your photo right on the first try though! We see it quite a bit in the urban landscape category.

• Road traffic: the last subject perfect for long exposure. Indeed, we can get beautiful yellow/white trails on the effects of vehicle headlight movements!
• Fireworks: also an excellent subject which lends itself very well to long exposure!

In order to understand how to shoot a long exposure, be aware that depending on the shooting conditions, the technique for this kind of shot will be different.
The essential point to understand is the following
The essential point to understand is the following: to do a long exposure and get such a result, it is necessary to increase the exposure time of the picture. It is by increasing the shutter speed that you obtain this blurry, milky effect on the sea, as if moving on a waterfall.

So how do you decrease the exposure time on a picture? You have three main options regarding the settings of your digital camera. This is the classic trio: Aperture, ISO, shutter speed. The three parameters are in fact directly linked to each other. These three elements will be covered independently in dedicated articles.

• The aperture: to increase the exposure time, it is necessary to close the diaphragm, therefore to look for the smallest possible aperture. As a reminder, the larger the number, the smaller the aperture is (it’s not easy to understand at first!). The difficulty is that, the more “you close”, the more the diffraction phenomenon appears, which affects the quality of the image. We will generally try to close around f/11 to f/14 at most. Despite this, in many shooting conditions, it will not be enough to achieve the desired effect (understanding the exposure time will not be long enough),

• ISOs: if you still do not have the desired long exposure effect by closing the diaphragm “as far as possible”, it is necessary to adjust the ISO sensitivity setting. Here too, we will try to increase the exposure time. In normal circumstances, we tend to increase the ISOs as soon as the luminosity is missing, so that you can take the picture more quickly. Here, it will be the other way around. We will lower the ISOs, as low as possible, to reduce the speed of the picture (ISO 100, or even 50 on some DSLR),

Now let’s quickly talk about shutter speed. You’re going to tell me, why not just slow down the shutter speed of the camera? Under certain conditions, this will be enough, but in the middle of the day, if you reduce the exposure time to 5 seconds for example, your photo will be completely overexposed (“burned” as we say). Simply put, there will be too much light coming to your camera… Your DSLR cannot, in high light conditions (e. g. full sun), do a long exposure without the use of an ND filter (neutral density filter).

The goal will therefore be, to understand how to do a long exposure, to play with these three parameters. In the next three paragraphs, I explain how to take a long exposure shot for three of the most common shooting situations (day, night and sunset / sunrise). It’s not rocket science, but the technique requires a minimum of practice and understanding.

Even if the shooting conditions influence the technique and the way you will do your long exposure, the general principle remains the same:

1. Find the subject you want to capture,
2. Place your camera on your tripod to stabilize your whole system (technique impossible handheld),
3. Focus on the composition and framing of the scene. Try to catch the attention here and frame it as well as possible,
4. Enable noise reduction on your DSLR (if you have the option),
5. Activate the mirror lock,
6. Cover your viewfinder (to prevent light from infiltrating and having a reflection),
7. Lock the lens stabilizer,
8. Set your DSLR to the remote control mode,
9. Use the aperture priority mode – the easiest way to start (Av at Canon and A at Nikon), by turning the knob on your camera,
10. Choose your optimal settings for the scene (ISO at the lowest and generally small aperture – f/11 for example -> we often seek a large depth of field in landscape photography).

These steps will be almost identical whether you do your long exposure with or without a filter, day or night. This is the basis.

For those looking for tips on how to do landscape and travel photography, I have written two complete articles on the subject.

To be able to take a long exposure picture during the day, the luminosity is such that the long exposure will be impossible without the use of an ND filter, or neutral density filter. For those who don’t know yet, I have written two complete articles explaining what an ND filter is for and how to choose an ND filter. The use of this type of filter will therefore be required and, depending on the desired effects on the photo, you will choose the density (opacity) of your ND filter. A third article explains in detail how to use an ND filter for a long exposure, technically speaking, depending on your ND filter (high or low density).

The basic principle is simple, it will be a matter of measuring the shutter speed given by the DSLR without the filter and adjusting this shutter speed according to the density of your ND filter. The objective is to darken the scene which has too much light, the ND filter allows only a limited amount of light to pass through depending on its opacity. The rest is only practical and technical. Remember that this accessory is essential for daytime long exposure.

When I talk about low-light conditions, I am essentially talking about the hours before and after sunset / sunrise (“golden hours” or “blue hour”). By the way, if you’re interested, I’ve written a complete guide to taking beautiful sunset pictures (tricks, technique, settings, equipment, etc.). To know how to do a long exposure during these hours, it is necessary to understand one thing. Here you have two possibilities for a long exposure:

Optimize the settings of your DSLR camera to the maximum

Unlike long exposure in the middle of the day, which necessarily requires the use of an ND filter, performing long exposures at the end of the day or early morning can be possible by only adjusting the settings of the camera (to a certain point).

All you have to do now is:

• Repeat the steps mentioned above,
• Choose a small aperture to increase the exposure time (e. g. f/11 to f/16),
• Lower the ISOs to the maximum of your camera (ISO 50 to the lowest on some digital cameras).

According to these settings, your camera will display to you the shutter speed at which it will take the picture (click halfway on the shutter-release button to get the info). It is up to you to determine if this is enough to do a long exposure. Depending on the desired effects, this technique may not be adequate, with the DSLR displaying between 1/5th and 1s/2s. If you want more pronounced effects of long exposure, you will need to use an ND filter to further reduce the exposure time, which brings us to the next point.

In any case, if the conditions are met, you can consider shooting and doing a long exposure without a filter here.

Use an ND filter to reduce exposure time

This brings us to the second option. I wrote an article to find out which ND filter to choose, you can refer to it. To simplify, if you want to achieve a slightly longer exposure, you should choose a low-density ND filter (ND 8 to ND 64). On the other hand, an ND400/ND1000 filter will allow you to completely give the sea a milky effect, for example. You can then choose between several types of filters (with filter holder or screw ones).

As a reminder, here is a table that shows the shutter speed without filter and the correspondence with different ND filters with varying degrees of opacity.

Be careful, however, not to use filters with too high a density (ND 400 or ND1000) in low-light conditions, as this may result in exposure times that are much too long. As opposed to what we discussed above, you will be forced to open the diagram (choose a larger aperture) or increase the ISO to compensate for the exposure time which would be too long (the opposite of what you will actually do during a long exposure).

For example, if your camera gives you 1/4 s without a filter, placing an ND 1000 filter at that time gives you a 4-minute exposure, which is not always necessary! This is why I very often recommend choosing an ND 64 filter (6 speed loss) for sunset and sunrise.

This is the simplest shooting condition for long exposure. Indeed, the brightness being already very low (normal it is night!), you won’t have to use an ND filter for long exposure pictures at night.

All you have to do is follow the steps mentioned at the beginning of this article and take your picture. However, it will sometimes be necessary to use the manual focus mode depending on the ability of your camera’s sensor to focus (remove autofocus).

Another point that I had already mentioned at the beginning of the article, at night, it is likely that, in many cases, long exposure is one of the only solutions to take a sharp picture.

Well, I hope you now understand how to do a long exposure at night, it really is the simplest case.

I quickly review the required equipment to do a long exposure. Indeed, a minimum of equipment will be necessary for this technique:

• The tripod: it is the essential element for long exposure, even if I have to admit that I have already made a few long exposures by placing the camera on a piece of wall or other… (but it is far from perfect and sometimes blurry in the end). Be aware that the slightest movement on your part will result in a blurry picture.

You can refer to the article to choose your tripod and according to which criteria. It will mainly depend on the weight of the equipment you have to load on the tripod (and of course your budget). Stabilization is the key word here.

• A remote control: there are several models: wired and wireless remote control. If you press the shutter-release button on your camera, it causes micro-shocks that will reduce the sharpness of your picture. I have personally owned this Canon remote control for several years, and I am delighted with it.

It is preferable to use a remote control to do a long exposure. Another possibility is to use the timer (10 seconds) on your camera.

• Extra batteries: this is an aspect that is sometimes forgotten. Performing long exposures tends to drain the battery much faster than usual. So if you are going to do long exposures for an evening or a sunrise, I advise you to have at least a spare battery (in addition to the one in your device that is fully charged).

• An ND filter or neutral density filter: This is discussed throughout the article. For the choice of your ND filters, you can refer to my article on how to choose your ND filter. For high light conditions (daylight) and even sometimes in low light, they are one of the essential accessories for long exposure.

Here are some references of ND filters (screw or square with filter holder) that I still use for my long exposures.

• An application for exposure times or a calculator: and yes because, unless you are very good at mental mathematics, it will be necessary. There are many applications that do this very well. You can also find on the net ready-made tables that present the shutter speeds with or without filter. Even better to see if you understand how it works, you can make a table for yourself on an Excel page (that’s what I do). You can print it, laminate it and put it in your camera bag.
• Finally, a polarizing filter screwed onto the front of your camera lens can be useful for long exposure photography. This photo filter can therefore be used incidentally to provide greater contrast and saturation on the scene when the picture is taken. However, attention should be paid to the phenomenon of vignetting, as soon as more and more filters are being used.

These are the necessary accessories for long exposure.

Last point of this very detailed article (too much?): the post-treatment of these long exposures. In most cases, it will indeed be necessary to work your long exposure pictures in an editing software. I have been using the famous Adobe Lightroom for years now or more recently the DXO software.

So why edit your photos? For 3 main reasons:

• White balance: depending on the type of ND filter used, it is possible that a slight tint may appear on the picture. Simply put, the colors of your photo do not represent reality. They can be warmer or colder. This can be easily rectified with a software program.

• Stains on the sensor: long exposure tends to mark your photo with spots. These are actually dusts located beforehand on your sensor and can be seen in your long exposures, as soon as you close the diaphragm too much (from f/11). This is very easily fixable with software, which will allow you to correct it.

• Noise correction: even if you have activated noise reduction, it is possible that your picture may have a slight texture. You can easily reduce this in post-processing.

I have come to the end of this article explaining how to do a long exposure. You can refer to the more detailed article to understand how to use an ND filter (neutral density filter) to technically perform a long exposure.

If you have any questions about this article, don’t hesitate to ask them in the comments! Be aware however that it will take you several tries, a lot of trials and errors before you really succeed in capturing your first correct long exposure shot. Your photo will initially be too dark, too bright, or blurry…. It can be a little annoying when you want to learn long exposure photography, but once you get used to it, everything just goes smoothly, or almost. To help you with your first attempts, do not hesitate to come and read the article on how exposure works in photography.

For photographers who doesn’t love long exposure?

See you soon for a new photo article,

Sylvain