10 Tips for Terrific Time-Lapses


eMotimo at Dino Park #1

Here are my top tips for shooting terrific still-image nightscapes … and time-lapse movies of the night sky. 

Canon 6D

1. Go for pixel size, not pixel count

When choosing a camera for night sky scenes, the most important characteristic is not number of megapixels. Just the opposite.

The best cameras are usually models with more modest megapixel counts. Each of their individual pixels is larger and so collects more photons in a given exposure time, yielding higher a signal-to-noise ratio – or lower noise, critical for night shooting.

Cameras with pixels (the “pixel pitch”) 6 to 8 microns across are best. Many high-megapixel cameras have tiny 4-micron pixels.

Large-pixel cameras are often the full-frame models, such as the Canon 5D MkIII and 6D, the Nikon D610, D750, and Df, and the Sony a7s and a7S II.

Many “cropped-frame” cameras are now 18- to 24-megapixel models with smaller, noise-prone pixels. They can certainly be used, but will require more care in exposing well at lower ISOs, and in processing to smooth out noise without blurring detail.

Manual Settings

2. Learn to fly on manual

While DSLRs and Compact System Cameras have amazing automatic functions we use none of them at night.

Instead, we use the camera on Manual or Bulb, dialling in shutter speed, aperture and ISO speed manually. We also have to focus manually, using Live View mode to focus on a bright star or distant light.

Learn the tradeoffs involved: Increasing ISO sensitivity of the sensor keeps exposure times down but increases noise. Opening up the lens aperture to f/2 or f/1.4 also keeps exposures short but introduces image-blurring aberrations, especially at the frame corners.

To prevent stars from trailing due to the sky’s motion adhere to the “500 Rule:” the maximum exposure time is roughly 500 divided by the focal length of your lens.

Histogram-Correct

3. Expose to the right 

At night, always give the sensor plenty of signal.

Use whatever combination of shutter speed, aperture and ISO will provide a well-exposed image. The image “histogram,” the graph of number of pixels at each brightness level shown above, should never be slammed to the left.

It should be a well-distributed “mountain range” of pixels, extending well to the right. If the 500 Rule restricts your shutter speed, and your desire for sharp images across the frame demands you shoot at f/2.8 or even slower, then don’t be afraid to bump up the ISO speed to whatever it takes to produce a good histogram and a well-exposed image.

Noise will look far worse if you underexpose, then try to boost the image brightness later in processing. Expose to the right!

File Format #2 7D

4. Shoot Raw!

Shoot Raw. Period.

When comparing Raw and compressed JPG versions of the same image, you can be fooled into thinking the JPGs look better (i.e. smoother) because of the noise reduction the camera has applied to the JPG that is beyond your control. However, that smoothing has also wiped out fine detail, like stars.

By shooting Raw you get to control whatever level of noise reduction and sharpening the image needs later in processing.

JPGs are also 8-bit images with a limited tonal range – or palette – in which to record the subtle gradations of brightness and colour present in our images.

Imported Raw files are 16-bit, with a much wider tonal scale and colour palette. That’s critical for all astrophotos when, even with a well-exposed image, many tonal values are down in the dark end of the range. Processing Raw images makes it possible to extract detail in the shadows and highlights.

Even when shooting a time-lapse sequence, shoot Raw.

LENR

5. Take dark frames (sometimes!)

LENR reduces noise.

It’s a topic of some debate, but in my experience it is always better to turn on the camera’s Long Exposure Noise Reduction (LENR) function when shooting individual nightscape images. Doing so forces the camera to take a “dark frame,” an exposure of equal length but with the shutter closed.

It records just the noise, which the camera then subtracts from the image. Yes, it takes twice as long to acquire an image, but the image is cleaner, with fewer noisy pixels.

This is especially true when shooting on hot summer nights (the warmer the sensor the higher the noise). That said, you cannot use LENR when shooting frames for star trail composites or time-lapse movies.

For those, the interval between images should be no more than 1 to 5 seconds. Using LENR would introduce unsightly gaps in the trails or jumps in the star motion in time-lapses.

As an alternative, it is possible to take separate dark frames at the end of the night by simply covering the lens and taking exposures of the same duration and at the same ISO as your “light frames.”

Some stacking software, such as StarStax and the Advanced Stacker Actions have places to put these dark frames, to subtract them from the stack later in processing.

811eBU4sBkL._SL1500_

6. Use fast lenses

A fast lens is your best accessory.

While the “kit zoom” lenses that come with many DSLRs are great for shooting bright twilight or Full Moon scenes, they will prove too slow for dark starlit scenes with the Milky Way.

In addition to exposing to the right and shooting Raw, the secret to great nightscapes is to shoot with fast lenses, usually “prime” lenses with fixed focal lengths. They are usually faster and have better image quality than zooms.

Your most-used lens for nightscape and time-lapse shooting is likely to be a 14mm to 24mm f/2 to f/2.8 lens.

Fortunately, because we don’t need (and indeed can’t use) autofocus we can live happily with low-cost manual lenses, such as the models made in Korea and sold under brands such as Rokinon, Samyang and Bower. They work very well.

The quarter Moon reflected in the waters of Reesor Lake, Alberta in Cypress Hills Interprovincial Park. Taken on July 5, 2014. This is with the 14mm Rokinon lens and Canon 6D at ISO800. This is a high dynamic range stack of6 exposures from 1/15 to 0.6 seconds taken just before using the camera to take a motion control time-lapse. The Moon was in conjunction with Mars (right of Moon) and Spica (left of Moon) but in the bright twilight they are not showing up here.

7. Get to know the Moon & Milky Way

For many nightscape and time-lapse shoots, the Moon is your light source for illuminating the landscape.

When the Moon is absent, the Milky Way is often your main sky subject.

Knowing where the Moon will be in the sky at its various phases, and when it will rise (in its waning phases after Full Moon) or set (in its waxing phases before Full) helps you a plan a shoot, so you’ll know whether a landscape will be well lit.

Astronomy apps for desktop computers and mobile devices are essential planning aids. A good one specifically for photographers is The Photographer’s Ephemeris.

Knowing in what season and time of night the Milky Way will be visible is essential if you want to capture it. Don’t try for Milky Way shots in spring – it isn’t up!

Me with cameras shooting time-lapses at Crawling Lake reservoir, Alberta, June 30/July 1, 2013. Perpetual twilight of summer solstice shines to the north and very weak noctilucent clouds.

8. Keep it simple to start

Don’t be seduced by the fancy gear. 

Time-lapse imaging has blossomed into a field replete with incredible gear for moving a camera incrementally during a shoot, and for automating a shoot as day turns to night.

I explain how to use all the fancy gear in my ebook, linked to below, however … Great time-lapses, and certainly still-frame nightscapes, can be taken with no more than a DSLR camera with a good fast lens and mounted on a sturdy tripod. Invest in the lens and don’t scrimp on the tripod.

Another essential for shooting multi-frame star trails and time-lapses is a hardware intervalometer ($50 to $150).

TC-80N3 Masked

9. Learn the intricacies of intervals

For time-lapses, an intervalometer is essential.

Mastering exposure and focus in still images is essential for great time-lapse movies because they are simply made of hundreds of well-exposed still frames.

But move to time-lapses and you have additional factors to consider: how many frames to shoot and how often to shoot them. A good rule of thumb is to shoot 200 to 300 frames per sequence, shot with an interval of no more than 1 to 5 seconds between exposures, at least for starry night sequences.

However, most intervalometers (the Canon TC-80N3 is an exception) define their “Interval” setting to mean the time from when the shutter opens to when it opens again. In that case, you set the Interval to be a value 1 to 5 seconds longer than the exposure time you are using. That’s also true of the intervalometer function Nikon builds into their internal camera firmware.

Test first!

The summer Milky Way with a meteor streaking at centre as a bonus. An aurora to the north off frame is lighting the foreground with a green glow. Haze and forest fire smoke obscure the horizon. I shot this at the Battle Scene viewpoint at Writing-on-Stone Provincial Park, in southern Alberta. Sagittarius and the galactic centre is on the horizon at left of centre. Capricornus is amid the haze at left of centre. On the horizon are the Sweetgrass Hills in Montana. The Milk River winds below amid the sandstone formations that are home to historic First Nations petroglyphs.  This is a single 30-second exposure with the Nikon D750 at ISO 3200 and Sigma 24mm Art lens at f/2, taken as part of a time-lapse sequence.

10. Go to beautiful places

While the gear can be simple, great shots demand an investment in time.

By all means practice at home and at nearby sites that are quick to get to. Try out gear and techniques at Full Moon when exposures are short (the Full Moon is bright!) and you can see what you are doing.

But beautiful images of landscapes lit by moonlight or starlight require you to travel to beautiful locations.

When you are on site, take the time to frame the scene well, just as you would during the day. Darkness is no excuse for poor composition!

While shooting nightscapes and time-lapses can be done with a minimal investment in hardware and software, it does require an investment in time – time to travel and spend nights shooting at wonderful places under the stars.

Enjoy the night!

I cover all these topics, and much more, in detail in my ebook How to Photograph & Process Nightscapes and Time-Lapses. Click the link below to learn more.

— Alan, September 16, 2015 / © 2015 Alan Dyer / www.AmazingSky.com

How to See & Shoot the Perseids


A trio of Perseid meteors shoot at left in the pre-dawn sky over Lake Minnewanka in Banff National Park. The overexposed waning crescent Moon shines between Venus (below) and Jupiter (above), with Jupiter near the Hyades and below the Pleiades in Taurus. Taken the morning of Sunday, August 12, 2012 with the Canon 5D MkII and 24mm Canon L-series lens. This is a composite of three exposures, one for each meteor, each for 40 seconds at ISO 2000 and f/5. Landscape is from one image, two other meteors from two other frames layered in and registered in the correct position in the base layer.

It’s Perseid meteor shower time. Here are tips for seeing and shooting the meteors.

What are the Perseids?

They are an annual meteor shower, perhaps the most widely observed of the year, that peak every year about August 12. They are caused by Earth passing through a dust stream left by Comet Swift-Tuttle, last seen near Earth in 1992.

Each “shooting star” is really a bit of comet dust burning up in our atmosphere as it ploughs into us at 200,000 kilometres an hour. They don’t stand a chance of surviving – and none do.

All Perseid particles burn up. None reach Earth.

Perseid meteor caught night of August 12-13 2009 from Cypress Hills Prov Park in Saskatchewan at the annual Saskatchewan Summer Star Party. One frame of 250 shot as part of a time-lapse movie. Taken with Canon 5D MkII and 24mm lens at f/2.5 for 30s at ISO1600.
Perseid meteor caught night of August 12-13 2009 from Cypress Hills Prov Park in Saskatchewan at the annual Saskatchewan Summer Star Party. One frame of 250 shot as part of a time-lapse movie. Taken with Canon 5D MkII and 24mm lens at f/2.5 for 30s at ISO1600.

When are the Perseids?

The peak night of the Perseids this year is the night of Wednesday, August 12 into the early morning hours of August 13, with the peak hour occurring about midnight Mountain Daylight Time or 2 a.m. on the 13th for Eastern Daylight Time.

For North America, this is ideal timing for a good show this year. However, a good number of meteors will be visible the night before and night after peak night.

Even better, the Moon is near New and so won’t interfere with the viewing by lighting up the sky.

In all, except for the mid-week timing, conditions this year in 2015 couldn’t be better!

Perseid meteor caught night of August 12-13 2009 from Cypress Hills Prov Park in Saskatchewan at the annual Saskatchewan Summer Star Party. One frame of 260 shot as part of a time-lapse movie. Taken with Canon 20Da and 15mm lens at f/2.8 for 45s at ISO1600.
Perseid meteor caught night of August 12-13 2009 from Cypress Hills Prov Park in Saskatchewan at the annual Saskatchewan Summer Star Party. One frame of 260 shot as part of a time-lapse movie. Taken with Canon 20Da and 15mm lens at f/2.8 for 45s at ISO1600.

What do they look like?

Any meteor looks like a brief streak of light shooting across the sky. The brightest will outshine the brightest stars and are sure to evoke a “wow!” reaction.

However, the spectacular Perseids are the least frequent. From a dark site, expect to see about 40 to 80 meteors in an hour of patient and observant watching, but of those, only a handful – perhaps only 1 or 2 – will be “wow!” meteors.

A pair of Perseid meteors shoot at left in the late night sky at the Upper Bankhead parking lot in Banff National Park. The  waning crescent Moon is just rising above the trees. A faint Perseid is at right, while a satellite trail goes from left to right as well.  Taken the night of Saturday, August 11 into the wee hours of Sunday, August 12, 2012 with the Canon 7D and 10-22mm Canon lens. This is a stack of two exposures, one for each meteor, each for 60 seconds at ISO 1250 and f/4. The stars are trailed slightly due to the two-minute exposure time in total.
A pair of Perseid meteors shoot at left in the late night sky at the Upper Bankhead parking lot in Banff National Park. The waning crescent Moon is just rising above the trees. 
Taken the night of Saturday, August 11 into the wee hours of Sunday, August 12, 2012 with the Canon 7D and 10-22mm Canon lens. This is a stack of two exposures, one for each meteor, each for 60 seconds at ISO 1250 and f/4. 

Where do I look?

All the meteors will appear to radiate from a point in the constellation of Perseus in the northeastern sky in the early hours of the night, climbing to high overhead by dawn.

So you can face that direction if you wish, but Perseids can appear anywhere in the sky, with the longest meteor trails often opposite the radiant point, over in the southwest.

Shows unusual Perseid meteor varying in brightness? Or is this a satellite that mimics Perseid for position (it comes right out of the radiant point).  Taken at SSSP, August 14, 2010, using Canon 5D MkII and 15mm lens.
Shows unusual Perseid meteor varying in brightness? Or is this a satellite that mimics Perseid for position (it comes right out of the radiant point). Taken at Saskatchewan Star Party, August 14, 2010, using Canon 5D MkII and 15mm lens.

How do I look?

Simple – just lie back on a comfy lawn chair or patch of grass and look up!

But … you need to be at a dark location away from city lights to see the most meteors. You’ll see very little in a city or light-polluted suburbs.

Head to a site as far from city lights as you can, to wherever you’ll be safe and comfortable.

How do I take pictures?

To stand any chance of capturing these brief meteors you’ll need a good low-noise camera (a DSLR or Compact System Camera) with a fast (f/2.8 or faster) wide-angle lens (10mm to 24mm).

Sorry, keep your point-and-shoot camera and phone camera tucked away in your pocket – they won’t work.

Set up you camera on a tripod, open the lens to f/2.8 (wide open perhaps) and the ISO to 800 to 3200) and take a test exposure of 20 to 40 seconds. You want a well-exposed image but not over-exposed so the sky is washed out.

Set your exposure time accordingly – most cameras allow a maximum exposure of 30 seconds. Exposures longer than 30 seconds require a separate intervalometer to set the exposure, with the camera set on Bulb (B).

Take lots of pictures!

To up your chances of catching a meteor, you need to set the camera to shoot lots of frames in rapid succession.

Use an intervalometer to take shots one after the other with as little time between as possible – because that’s when a meteor will appear!

Barring an intervalometer, if you have standard switch remote control, set the camera on High Speed Continuous, and the shutter speed to 30 seconds, then lock the remote’s switch to ON to keep the camera firing. As soon as one exposure ends it’ll fire another.

Twin Perseids in this photo? Or are these satellites?  Taken at SSSP, August 14, 2010, using Canon 5D MkII and 15mm lens.
Twin Perseids in this photo? Or are these satellites? Taken at SSSP, August 14, 2010, using Canon 5D MkII and 15mm lens.

What else do I need to know?

• Focus the lens carefully so the stars are sharp – the Live Focus mode helps for this. Focus on a bright star or distant light.

• Aim the camera to take in a wide swath of the sky but include a well-composed foreground for the most attractive shot.

• Aim northeast to capture meteors streaking away from the radiant. But you can aim the camera to any direction that lends itself to a good composition and still capture a meteor.

• To increase your chances, shoot with two or more cameras aimed to different areas of the sky. Meteors always appear where your camera isn’t aimed!

• Be patient! Despite shooting hundreds of frames only a handful will record a meteor, as only the brightest will show up.

Can I track the sky?

If you have a motorized equatorial mount or a dedicated sky tracking device (the iOptron Sky Tracker and Sky-Watcher Star Adventurer, each about $400, are popular), you can follow the stars while taking lots of shots. This avoids the stars trailing and allows you to use longer exposures.

The video above shows a Star Adventurer tracking the sky as it turns about its polar axis which is aimed up to a point near Polaris. Click the Enlarge and HD buttons to view the video properly.

Polar align the tracker, but then perhaps aim the camera to frame the summer Milky Way overhead. Take lots of 1- to 3-minute exposures, again at f/2.8 and ISO 800 to 1600. Some exposures will pick up meteors – with luck!

Tracking then stacking

Later, in processing, because the sky has remained fixed on the frame, it’s then possible to stack the images (using a “Lighten” blend mode on each image layer) so that the final composite frame contains more meteors, for an image with lots of meteors captured over an hour or more of shooting.

While it is possible to stack shots taken on a static tripod to produce such a meteor composite, doing so requires a lot of manual cutting, pasting and aligning of meteor images by hand. The result is a bit of a fake, though I’ve done it myself – the image at top is an example, though with only a trio of meteors.

Good luck and happy meteor watching!

– Alan, August 6, 2015 / © 2015 Alan Dyer / www.amazingsky.com