Night sky time-lapse photography videos can range from fairly simple movements of the moon and stars right up to the incredibly impressive ‘Holy Grail’ – day-to-night – transitions.
In this complete tutorial, I’m going to share my tried-and-tested methods of how to do time-lapse photography with you.
I will walk you through all of the techniques, equipment, and software needed to help you make top-quality time-lapse videos of the night sky that will impress everyone that views them.
What Is Time Lapse In Photography And How Does It Work?
A time-lapse video is created from a series of individual still images, that are combined together as a video sequence, using appropriate post-processing software.
The camera is set up to take a large number of individual shots, often many hundreds of images. All depending on the length of the finished sequence.
This creates the visual effect of the passage of time, all within a short video sequence. An interval (or a gap) is placed between each shot the camera takes to produce the time-lapse effect.
The length of the interval determines the overall length of the finished sequence. Longer intervals will condense the same number of shoot hours into a shorter time-lapse video.
The Two Different Time-Lapse Methods
When it comes to time-lapse photography, you’ll come across two different types of time-lapse… time-lapse video and time-lapse photo.
The main difference between the two is the technique used to capture the actual time-lapse sequence and not the final output of the time-lapse.
Regardless of the initial method used (video or photo), the final output will always be in video format.
When it comes to night photography, my preferred choice is the time-lapse photo method. Here are a few reasons why:
- Photos don’t have any limit of exposure per scene compared to video
- Photos can capture more light in each image over video
- The physical resolution per frame can be much higher than video
So as you can see, when we do night photography, we need to capture as much light as possible in each image frame.
Can I do time-lapse photography with a smartphone?
In a word, maybe.
If your smartphone is compatible with an intervalometer and allows for aperture and shutter speed adjustments, then yes.
Essential Kit for Time Lapse Photography
Below is a list of all the gear that I use throughout my timelapse shoot. While not everything on the list is mandatory, each one will make your life that little bit easier.
- Camera – Any camera that can be set to manual exposure and has a connection for an intervalometer. See Camera Considerations below.
- Lens – the wider and shorter the better. See Lens Considerations below.
- Tripod – The sturdier the better to keep each separate image pin sharp.
- Intervalometer – A clever piece of kit that will do the hard work for you. See Setting Up the Intervalometer, below.
- Memory Card – The bigger the better as you may be shooting hundreds of separate images.
- Level – Essential to ensure that the camera is straight and level on the tripod. Some cameras have built-in electronic levels. Small, clip-on camera spirit levels also do a good job.
- Viewfinder Cap – Often supplied with the camera or bought separately. Stops light from entering the lens at the rear of DSLR cameras, during long exposures. A piece of black tape is a useful substitute.
- Weather App – A smartphone weather app with accurate hourly updates.
- Calculator – To quickly work out the shutter speed and time intervals.
- Software – For post-processing, the photographs you take to produce a short video. See Software Considerations, below.
- Flashlight – To find your way around in the dark and to illuminate the buttons on your camera and intervalometer. Narrow beam, handheld, or Headband models are best.
- ND Filters – Neutral Density (ND) filters block out light entering the lens without affecting other aspects of the image. Because they also slow down the shutter speed, they are not suitable for night sky time-lapse photography.
Any camera that allows you to make manual mode setting adjustments and to control the ISO and white balance will work well for time-lapse photography.
You can use any camera that allows you to change its settings. This includes full-frame, cropped sensor DSLR, mirrorless, and Micro 4/3rds cameras.
You will be able to create excellent time-lapse photography with cameras using a range of sensor sizes, including full-frame, APS-C, 4/3rds, and 1-inch sensors.
However, some of the calculations you need to make for the image exposures may vary according to your camera’s sensor size. This will be fully explained below.
Camera With or Without Intervalometer?
Using the built-in intervalometer (if your camera has it) is possible to use but i find it limiting. I much prefer using an external intervalometer.
Any camera with a remote shutter release port will be fine. Just make sure that you use an intervalometer with the correct cable and connector that fits your camera.
JPEG or RAW
Another useful consideration is that the camera should be capable of producing Raw image files. Raw files allow you to get more control over the images at the post-processing stage.
They are also larger than JPEG image files, which means that, although they take up more hard drive space, the quality of your finished time-lapse videos will be excellent.
Most digital cameras can shoot Raw files these days, but don’t worry if yours doesn’t. You can still follow this tutorial using JPG image files.
Night sky photography needs a wide-angle lens on the camera, to ensure that as much of the sky as possible is visible in the frame.
A wide-angle lens is one that has a short focal length. A number, measured in millimeters (mm), usually found at the top of the lens barrel, will tell you its focal length. Any focal length shorter than 24mm will work well for night sky photography.
However, the shorter the focal length of the lens, the wider the angle of view. So, a lens with a focal length of 10mm will take in much more of the sky area than a lens with a focal length of 24mm.
Zoom or Prime Lenses For Shooting A Time Lapse?
Wide-angle lenses are available as zoom lenses or as fixed focal length prime lenses.
Wide-angle zooms provide a range of focal lengths, perhaps from 10mm at the widest end, reducing the angle of view to 20mm at the other end, for example.
Alternatively, a fixed focal length lens – known as a ‘prime lens’ – has only one focal length, which cannot be altered. Prime lenses can be (but not always) less expensive and lighter than zooms.
A significant difference is that prime lenses may offer wider maximum apertures than zoom lenses. This can be very important when setting your camera up for night sky time-lapse photography. More on this below.
Step-By-Step Tutorial To Time Lapse Photography
How to Find the Right Location
Light pollution can ruin night sky time-lapse photography by overloading the sensor with ambient light. Be very careful to avoid shooting locations where there is a lot of artificial lighting for your night sky photography.
Ideally, drive away from your town or city into the countryside or mountains where there are as few man-made lights as possible.
You can find maps online, showing designated Dark Sky Places, with very low light pollution. A great resource is: https://www.darksky.org/
How to Compose the Perfect Shot
Take time to scout out the best place to set up the camera within your main location. This is probably best done before dark.
Shots of the sky only, without other objects in the frame, can be quite dull. Find something of interest to put in front of the sky itself to grab the viewer’s attention.
This might be a tree, a building, or even an interesting vehicle, like an old farm truck, should you be lucky enough to find one.
Be careful not to block too much of the sky with your foreground object. Setting it low down or to one side of the frame can work well visually.
Watch the Weather
A weather app on your smartphone that gives accurate, hourly forecasts is an essential tool to help you plan a night sky time lapse.
Finding that the night sky conditions have changed drastically halfway through a 4-hour shoot can be very disheartening.
Bear in mind that the weather you need for your shoot depends on the type of time-lapse video you want to create.
When making a time-lapse of the moon transiting the sky, you will need to know when the moon (and what type of moon) will be in the sky.
If you are aiming to shoot a starry night, you will need to ensure that the sky will be mainly clear and full of stars.
However, thin and fast-moving clouds, spread across the total shooting time, can give a starry-night time-lapse some added visual interest.
So, observe the weather, before and during the shoot, as it will make or break your night sky time-lapse creations.
Camera Settings & Shooting Intervals
For a great night sky time-lapse, you need to do two essential things:
Firstly, make sure that the shot will be correctly exposed – that is, the night sky will not be too bright or too dark.
For a time-lapse video being shot entirely at night, this will be the same exposure set for the entire duration of the shoot.
Secondly, you will need to know how many individual exposures (shots) you need to take to create the sequence.
Getting the Exposure Right
There is more than one way to make a correct exposure. The method I will outline here will produce the most consistent and best quality results. It is also possibly the least complex.
It requires you to adjust three camera settings; the aperture, the shutter speed, and ISO.
Before you can do this, the camera needs to be set to manual exposure mode. The letter M usually designates this on the exposure dial.
In manual mode, set the widest aperture that is available on your camera – up to f2.8.
Those of you using zoom lenses, including the ‘kit’ lens that came bundled with your first DSLR camera, may find that the maximum aperture available is f3.5 or f4.
That is perfectly fine, although it may require a longer exposure time or higher ISO setting than needed for a lens with apertures that open up to f2.8.
You may own a lens with an aperture that opens wider than f2.8, and if so, I need you to trust me when I ask you not to go there.
My preference, even when using lenses with apertures that can open up wider, is to use f2.8 as my maximum aperture setting.
I do this because the focusing latitude at very wide apertures, such as f2, f1.8, and f1.4, is extremely narrow. In the dark, when pointing your camera at a tiny dot of light, like a star, you need a little bit of extra focusing leeway.
Shutter Speed Setting
When setting the shutter speed in manual mode, we have to ensure that it is not so long that it creates a blurred or fuzzy appearance to the night sky.
If the shutter speed is set beyond a certain amount of time, the rotation of the Earth will cause the beginnings of star trails, rather than sharp points of light in the night sky, which are what we need for time-lapse photography.
To ensure that star trails are avoided, you will need to make a calculation using the ‘500 Rule’.
The 500 Rule
To calculate the maximum shutter speed to set to avoid star trails, you need to divide 500 by the focal length of the lens.
For example, if your prime lens has a focal length of 20mm, then the 500 rule calculation to make is:
500 / 20 (focal length) = 25 (seconds)
In this case, 25 seconds is the longest shutter speed you can set if you want to avoid star trails in your images. Preferably, set a shutter speed shorter than that number, just to be safe.
However, there is a slight catch, as this method only works with a camera using a full-frame sensor. If your camera has a cropped APS-C or Micro 4/3rds sensor, there is an additional calculation.
Nikon APS-C DSLR camera sensors have a crop factor of 1.5, Canon APS-C sensors have a crop factor of 1.6 and Micro 4/3rds camera sensors have a crop factor of 2.
These numbers need to be included in the 500-rule calculation. To find the correct maximum shutter speed, you need to multiply the focal length of the lens by the crop factor, then divide 500 by that number.
For example, if you are using a Nikon camera with the ‘kit’ APS-C zoom lens, set at 18mm; the 500 rule works like this:
18 (focal length) * 1.5 (APS-C crop factor) = 27
500 / 27 (focal length * APS-C crop factor) = 19 (seconds)
So, in this case, 19 seconds (rounded up from 18.5) is the maximum shutter speed you need to set to avoid star trails.
It’s a lot simpler than it might first appear, and you will soon get the hang of working this out for your camera’s sensor.
If you’re not sure what type of sensor is in your camera, doing a Google search for the make and model number of your camera – followed by ‘crop factor,’ should find it quickly.
Setting the ISO
ISO is an abbreviation for International Standards Organisation, and it was initially used to designate the ‘speed’ or sensitivity to light of camera film.
On digital cameras, the ISO setting is used to adjust the sensitivity of the sensor, in effect fooling it into behaving as if the scene is brighter than it is in reality.
Most cameras have ISO settings that start at 100 or 200. As the ISO setting is increased from the starting point, a shorter exposure will be needed to produce the image at the same level of brightness.
When the ISO number is doubled – as from 100 to 200 ISO, the sensor needs half as much time to make the same exposure. If the ISO is increased from 200 to 400, the sensor now needs four times less light than it did at 100 ISO, and so on.
Many digital cameras have ISO settings reaching way up into the thousands, meaning that extremely dark scenes can be exposed without setting the shutter speed for several minutes, or even hours, for a single shot.
However, as the ISO level increases, so does the amount of noise (digital distortion) in the image. Photographs taken with very high ISO numbers may have colored blotches or lots of black dots, like a close-up of a newsprint, appear on them.
For night sky time-lapse photography, the dark sky and the fact that we need to keep the shutter speed quite short dictates that we should use a reasonably high shutter speed.
To avoid excessive noise, take the ISO only as high as it needs to go to get the shutter speed you need.
The Starting Exposure
With the aperture set to the widest available on the lens, up to f2.8, and the shutter speed set to not longer than that calculated using the 500 rule, your starting exposure is two-thirds done.
You can now use the ISO setting to control the final exposure in the image.
When you are ready to shoot the time-lapse, set the ISO reasonably high, perhaps to 800 as a starting point.
Don’t expect this to work correctly, right away. You will need to make some test shots and adjustments to the ISO, under the lighting conditions for the time-lapse shoot. See Putting It All Together, below.
Calculating the Interval Between Exposures
Now, we need to calculate the interval that will be placed between the individual images during the time-lapse shoot.
This is not as tricky as it first seems, so long as you have some other things decided in advance. These are:
- How long you intend shooting the scene time-lapse scene.
- How Long you intend the finished time-lapse sequence to play.
- The frequency rate for your video playback – usually stated in ‘frames per second.’
Let’s say that you are planning to photograph the night sky, for 2 hours of total shoot time.
We will also assume that you plan to turn this into a time-lapse video that will play for 1 minute, at 24 frames per second (fps), which is the standard playback time.
To calculate the interval (gap), you need to leave between shots, do the following:
- Convert the playing time and total shoot time into seconds
- Multiply the playing time by the frequency rate (24 fps)
- Call this sum 1.
- Divide the total shoot time by sum 1.
The result is the interval to be left between exposures in your camera.
So, our calculation looks like this:
60 secs (playing time) x 24 fps (frequency rate) = 1440
7200 secs (total shoot time) / 1440 (sum 1) = 5 seconds
For this time-lapse shoot, you will need to set a 5 seconds interval between each separate exposure, using your intervalometer.
Over a 2-hour (7200 seconds) shooting period, this will produce a time-lapse video that plays for 1 minute (60 seconds).
Write the interval number down and set it aside, as you’ll need it when setting up the intervalometer.
Setting Up the Intervalometer
An intervalometer is an electronic timer that looks a bit like a cable release, which connects to the camera. It allows you to preset a range of shutter operations and trigger them automatically.
They are relatively inexpensive to buy, and every night sky photographer should have an intervalometer in the kit bag.
With an intervalometer, you can automatically set a delay before the shutter fires, set a timed interval between exposures, shoot a specified number of images and keep the shutter open for much longer than the camera allows.
Because you will be controlling the exposure from the camera settings, you only need to be concerned about two settings in the intervalometer. These are Interval and Number.
Interval sets up the intervalometer to put a timed delay (a gap) between each shot that the camera takes.
Most intervalometers will allow intervals to be set between 1 second and 100 hours. You will only be working in seconds for most time-lapse photography sequences.
You set the interval that you worked out using the method described in Calculating the Interval Between Exposures, above.
With that number in mind, move the selector bar under the word ‘Interval’ at the top of the intervalometer window and dial it in.
Number sets up the specific number of images that will be taken by the camera, automatically, after which it will stop shooting. These can usually be preset between 1 and up to 999 shots, depending on your particular intervalometer.
You will decide in advance how long the time-lapse shoot will take. So all you need to do is set the intervalometer to take an infinite number of shots, and stop it yourself at the end of the shoot.
Move the selector bar to ‘Number’ and dial down past the maximum number of shots available. You will then see two small lines (- -)., which is the Infinity setting. Select that, and the intervalometer will keep shooting until you stop it manually.
Focusing the Camera
This can be the trickiest part of the set-up process, but with practice and a little patience, it will get easier and faster.
Make sure that your DSLR camera is set to Live view, as there will not be enough light to use the viewfinder. With a mirrorless camera, ensure that the back-screen is on.
The camera’s auto-focus (AF) system will struggle to find and lock on to any distinct object in the night sky, so set the focusing switch to manual (not auto-focus).
The MF switch is usually on the lens. You may also need to press a switch on the body, with some cameras.
Turn the focusing ring on the lens to the infinity mark, which looks like a figure eight on its side (∞). Then, find the brightest object within your frame. If necessary, magnify the live view or back-screen for a clearer view.
Gently rotate the focusing away from and then back towards the infinity mark, until your bright object becomes a pinpoint.
Stars and bright light will become bigger and more diffused when they are out of focus. Turn the focusing ring in the opposite direction if your focusing point is growing fatter.
If you are finding it tricky to focus on the sky, look for other bright objects, such as the moon or distant town lights.
Putting it All Together: Time Lapse Checklist
Here is all the theory we have covered in a practical time-lapse to-do list. Print it out, keep it in your camera bag and follow it carefully for excellent time-lapse videos every time.
- Set the camera on a sturdy tripod and carefully frame the scene, using a foreground object where possible.
- Check that the horizon line is level, using the built electronic level or clip-on camera size spirit level.
- In manual exposure mode, open the lens to the widest possible aperture available, but not more than f2.8.
- In manual exposure mode, set the shutter speed to the maximum allowed to avoid star trails.
- Set the ISO to 800.
- Focus the lens and take a test shot.
- If the image is too dark, increase the ISO by 1/3rd of a ‘stop’ (one click of the dial). Take another test shot. Repeat this process until the image looks correctly exposed.
- Plug the intervalometer, preset with the calculated intervals, and the number set to infinity, the camera.
- Cover the viewfinder (if necessary) with a viewfinder cap or black tape to prevent excess light from entering the lens during long exposures.
- Press start on the intervalometer and note the predetermined stopping time.
- Keep warm and have some soup.
- Stop the intervalometer at the end of the predetermined shooting time.
Post-Processing the Images
There are a variety of ways in which your individual images can be post-processed into a time-lapse video, and this may involve using more than one software editing package.
My method of choice is to process the still images, initially, in Adobe Lightroom Classic software to ensure that they all match each other in terms of exposure brightness, tonal balance, and sharpness.
If the still images have been taken under the same lighting conditions, with the same exposure settings, I edit one image to correct the exposure and color tone and add sharpening if needed.
I then batch process all the rest (even many hundreds) to the same settings, in the Develop module, with one click.
Once the images are processed, I move to the slideshow module. There is very little to do here other than make sure the slideshow will be running at 24 frames per second. I use a free plug-in for this, as it’s not a standard Lightroom setting.
Then, all I need to do is select my chosen playback option in the export window. Lightroom will then create my time-lapse video and save to wherever I want on my hard drive.
Here is a great example of what a finished time-lapse can look like.
In this complete tutorial, I have covered everything you need to get started on making your own great night sky time-lapse videos.
While some of the information may be unfamiliar to you, going over it a few times on paper and making the odd mistake in practice, and learning from them, will soon have you producing astonishing time-lapse videos of your own.