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Category Archives: Time Lapse

How to Photograph Star Trails: The Ultimate Guide

By Christopher O’Donnell on 10 Jul 2011

Photographing the night sky can be a surreal experience, and star trail photography is highly rewarding if you have a bit of patience. Those 2 hour long single exposures can turn an otherwise mundane day shot into an otherworldly image.

Racing Stars
Racing Stars by Andrew Stawarz, on Flickr

When photographing star trails, your goal is to allow your camera to pick up light it wouldn’t normally by using extra long exposures. Working under the night sky means that the amount of available light is severely limited – most likely, you’ll only be able to capture the stars in the sky depending on if there are other light sources around, unless you’re planning on spending a few hours for each exposure.

Behind the Rocks at Night
Behind the Rocks at Night by Scott Ingram Photography, on Flickr

With that being said, it’s very important to utilize proper long exposure techniques: locking your mirror, mounting your camera on a secure tripod, and using a remote cable release for your shutter.

However, there are additional things to consider when photographing star trails that will set your night images apart from the crowd – how do you get those fantastic lines of light?

The Celestial South Pole
The Celestial South Pole by lrargerich, on Flickr

There are two methods popular with star photographers – using one very long exposure (long enough to register some noticeable star movement; at least 30 minutes) OR taking many shorter exposures and stacking those images in a way that shows sequential movement.

One Long Exposure

To capture star trails using one long exposure, there are a couple important things to consider. You need to let as much light into your lens as possible for those stars to register (the why’s of this are explained below) – this means using a fast lens, preferably in the f/2.8 range.

When photographing stars under one exposure, you need to do it during a new moon night – meaning that the moon is nowhere to be seen. If you have anything more than a crescent, your exposure will be limited to the 10-minute range because of the ambient light, which won’t do much for star trails. For this kind of photography, darkness is your best friend.

Ultimately, you’re aiming for your environment to be illuminated by the stars themselves – yes it’s possible! However, this entirely depends on the length of your exposure. The image below is the result of an 80 minute exposure taken under a new moon – you can see that the foreground is exposed nicely and the star trails are outstanding.

 

The vortex in the sky

The vortex in the sky by .Bala, on Flickr

 

When calculating your exposure, it would be best to do a shortened test shot so you’re not waiting a ridiculous amount of time just to see if your settings are correct. Many night photographers will jack up their ISO as far as it’ll go and shoot wide open – you’ll rarely find an instance where you’ll be taking a photo shorter than 30 seconds here. Of course the test shot will be entirely unusable due to noise and lack of trails, but it will give you a base to calculate what settings are needed with an ISO of 100.

Image Stacking Shorter Exposures

An alternative to waiting an hour or more for your exposure to finish is to take sequential images and stack them together in post process to get your star trails. In short, your exposure should be just long enough to register your stars as bright objects in the sky before moving onto the next one. It’s not uncommon to have several hundred images to stack taken over the course of a few hours.

Post process software such as ImageStacker and DeepSkyStacker will automatically throw all your images together and produce a stunning star trail.

Another benefit to image stacking is that you have all the necessary photos to make a time lapse video – here’s a short clip of what you can accomplish with this method of star trail photography: both the time lapse video and the composite trail image are shown here.

Tip: Between shots, try waiting a few seconds to let your sensor cool down a bit as a hot sensor = more digital noise.

Aperture: Wide Open or Narrow?

A common question – or rather misconception – with star trail photography is why wouldn’t you use a small aperture (say f/8 or above) for a sharper image rather than shoot wide open? You’re already shooting hour-long exposures so the timing isn’t a concern….surely it’s better to have a sharper photo, especially if you have other focal points (foreground interest, etc).

The issue with photographing stars is that they move – this is why we want to photograph their trails in the first place. With that in mind, there is a delicate balance to find with your exposure that’s more than just how long your shutter is open.

Wider apertures allow for shorter exposure times because they let more light in than narrow apertures. Focus on that last part – they let more light in. Considering that stars are constantly moving, you need to make sure that they’re registered on your sensor before they move – otherwise your star trails will be very dim, perhaps even non-existent depending on your chosen f/stop. Imagine doing a two-hour shoot where your foreground is lit nicely, but your star trails look no more than a slight variation in tones on the night sky.

Considering this, it’s a good idea to have a lens that’s capable of very wide apertures – such as f/2.8 or even wider. The wider your aperture, the brighter your star trails will be.

 

Finding the Poles

As you may have noticed, several of the example images used here have a circular pattern around a more central location- also known as the north and south poles. This is especially apparent in the video link above. In order to replicate this, you need to locate the poles first and aim your camera for it.

If you’re an astronomy beginner like me, this may seem a bit daunting – not to worry though. If you’re shooting towards the north pole, the Polaris (a.k.a. the North Star) is what you’re aiming for – it’s the last star on the handle of the Big Dipper, so if you locate that you’re good to go.

The south pole is a bit more difficult to eyeball as there’s no prominent bright star near the pole to help like the Polaris. You can still gather an idea of where it is though by using this free software to help pinpoint the south and north poles – very handy.

 

More Tips

Light Pollution – Whether from a nearby city or the street lamp at the end of your driveway, light pollution can greatly affect long exposures. This isn’t necessarily a bad thing though – in fact, it may add to the ambiance of your photo, such as a star trail image that begins during the blue hours. Experimenting with atmospheric light can be a creative way to make a unique star trail image – just be aware that the lighter your sky is, the less contrast your star trails will have.

Clear Skies and Dry Air – Obviously you don’t want to photograph star trails under a cloudy sky, but other atmospheric filters can interfere with your night photography – air pollution and humidity being the top annoyances. The best locations for a clear sky would be high up and away from any congested cities, and take on a night with very low humidity.

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Read more great articles by Christopher O’Donnell on his website or follow him on Facebook and Twitter.

via How to Photograph Star Trails: The Ultimate Guide.

 
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Posted by on July 11, 2011 in Featured, Landscape, Technique, Tutes & Tips, Time Lapse, Worth a Look

 

How to Master Ghost Photography

By Christopher O’Donnell via Light Stalking

If you’ve seen photos of ghostly apparitions and wonder how they were captured, most likely they were not doctored or otherwise created in post process. Your camera has the fantastic ability to capture unique effects, including those often mistaken for ghosts and spirits.

Wall Of Heroes
Wall Of Heroes by starfish235, on Flickr

Ghostly images like seen above are created with the use of a slow shutter speed. If you’re not familiar with how your shutter speed can affect your final image, read my article here which explains it in great detail.

Before we get started, you should know that there are a few pieces of equipment needed to execute this technique:

1. DSLR Camera

…or at least a camera that you can control your shutter speed with. While you could probably get away with a point-and-shoot, your control will be rather limited.

2. Tripod

In order to have full control over your camera and avoid any unwanted blurring, a tripod is needed to help stabilize your scene. Again, you could get away without one, but you run the risk of camera shake – not to mention being without a tripod will greatly limit your angles and vantage points.

3. Remote Shutter Release Cable

This is to ensure that you don’t touch the camera when you press the shutter button, which is one of the most common ways to cause camera shake.

4. ND Filters

Whether you purchase the slot-in filters or the threaded, an ND filter is necessary for daytime ghost photography in order to limit the amount of light that hits your sensor.

Types of Ghost Photography

Typically, there are two identifiable types of ghostly images that are captured in unique ways:

1. The Transparent Figure

The transparent figure, which is quite haunting, is executed by the use of a perfectly still model combined with an extended shutter speed. You’ll have to experiment with this method as it is very dependent on your environment (amount of available light, your aperture, etc).

I am the master of my fate: I am the captain of my soul.
I am the master of my fate: I am the captain of my soul. by Aristocrats-hat, on Flickr

Typically, you’ll need a shutter speed of a few seconds or longer to allow for enough exposure time. The goal here is to have your model remain perfectly still, but only for a fraction of the exposure. This will allow for your camera to register an identifiable figure in sharp detail, but be transparent since the model wasn’t in frame the entire time.

When moving out of frame, do so quickly to avoid any blurring. You’re basically combining two photos in one here -one with you in frame and one without – so any slow movement in between will register.

2. The Flowing Figure

In contrast, the flowing figure actually depends on fast movement to be executed properly. Since your creating a somewhat transparent blur, there is no need for sharp detail.

ghost walk
ghost walk by Pedro Moura Pinheiro, on Flickr

Like with the transparent figure, this will take some experimenting as your shutter speed will vary on the amount of light you have. It’s important to move fast during the exposure so that the human shape is still somewhat recognizable, but greatly blurred.

For a truly ghostly effect, wear flowing clothes or even drape a bed sheet over your shoulders. When you combine this with moving briskly throughout your frame, your figure will appear more haunting.

Also make sure to create the environment. Since you’re going for a haunting image, your final photo will be enhanced by your surroundings. Pick a location that compliments the mood you’re going for – this will only be beneficial to your photo.

For more inspirational ghost photography, please visit this Youtube video. It’s a collection of images by photographer Cole Thompson, which prove to be stellar examples of this process.

Read more great articles by Christopher O’Donnell on his website or follow him on Facebook.

via Light Stalking » How to Master Ghost Photography.

 
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Posted by on May 30, 2011 in Featured, General, Technique, Tutes & Tips, Time Lapse, Worth a Look

 

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Tips For Getting Started With Time Lapse Photography

Image from fixthisphoto.com

Image from fixthisphoto.com

by Ian Sheldon on PictureCorrect

If you’re a keen amateur photographer or even a pro and want to have a go at time-lapse photography and time lapse film making, I’ve listed some top tips to help you get started. It takes time to learn how to make the amazing time lapse videos some professionals have put online, however, for simpler applications, and just to get you started, I’m going to give you ten top tips. Here goes…

1. If you have a camera with a built in intervalometer (timer) that’s great. If not, you’ll need to go shopping to buy an intervalometer. They are more commonly called ‘remote control triggers’ nowadays. But just make sure they have an ‘intervalometer’ function; that is a function that allows you to set up to take images at pre-set intervals. There’s no use me recommending any intervalometers or remote devises here – as it really depends on what camera you have. But a bit of web research should give you some ideas of which one may be best for you. Before you get started properly, get to know the intervalometer and what it can do.

2. Timing is all-important. Like a good comedian, a good time lapse photographer must get his/her timing right! The most common error for all time-lapse newbie’s is setting unrealistic intervals between exposures. If the intervals are too long, you wont have sufficient frames to do an edit. It is better in some ways if you have too many (as you can always ‘lose’ some). But just be aware that too many may mean your camera having problems with processing. Plus, you don’t necessarily want to work the shutter on your camera too much! Setting the interval time between exposures is something that will come with practice and experience. You end up getting an instinct for it. But, a few things to bear in mind to help you are to A) think how long you want the time lapse sequence to last, and B) hold in mind that your edit will be sequenced at around 25fps (frames per second). Think! You’ll have to get 25 exposures / frames for 1 second of sequence. Someone once asked us to take 4 frames over 24 hours for a week and edit a time-lapse sequence for them…….until we pointed out that the ‘sequence’ would only run for a fraction over 1 second!

3. Camera settings are important, and these all depend on the type of time-lapse you do and the various factors involved. It can get quite complex. But, to get started, just set the camera on AV (aperture value), set your f-stop modestly to around 4 and just a few hundred on your ISO (we don’t want noisy images). This should give you a nice balance between controlling your camera and letting your camera decide some things for itself.

4. Get a tripod. It may sound obvious. But we’ve seen people trying to do time lapse by perching a camera precariously somewhere where it can easily be knocked. Remember, time-lapse photography and film-making only works by getting images that are captured from exactly the same fixed position. If you see a sequence edited together from frames that are different – because of camera movement – you’ll see the whole sequence shaking and wobbling! No good! A tripod, locked into position will give your camera a nice stable platform.

5. Get a decent size memory card. It may sound obvious again, but it’s another common error. As the proverb says, ‘You have to cut your cloth according to your coat’. Take a test image. What is the file size that the image is coming in at? Now multiply this by the number of images you’ll be taking. Is your card big enough? No? Then you’ll need to do either the following OR a combination of the following: a) get a bigger card b) reduce the file size (quality) of your captures c) do a card-swap at necessary intervals (taking care not to knock your camera). The real experts may output to an external storage device…. They may insist on bringing their images in HD (high definition) and creating HD time lapse movies…. but I’m trying to keep things simple for you here!

6. Be aware of power issues. Again, if you are time-lapsing using a camera with a single battery, you’ll need to be aware that it will run out relatively quickly. You’ll know how quickly if you know your camera. To solve, you can use a battery grip to extend the time you have, or even better, get an ac adaptor and plug your camera into the mains!

7. Do indoor projects first. You can control your environment and the lighting this way. Outdoors, you potentially face greater challenges; the weather, changes in light, away from power sources and so on. We know people who have wrecked very expensive DSLRs by leaving them unprotected out and not noticing its been raining!

8. Stick to things that wont take too long to capture at first. What about an ice cube melting, for a really short time lapse? Then, as you become more ambitious and experienced, you could always progress to cress seeds growing or an indoor potted flower opening. A simple favorite is to deprive an indoor plant of water for a while, then water it and time-lapse its recovery! Another great one is to place a white flower in water, add food colouring to the water and time lapse the nice effect of the colour climbing up the flower as it drinks….

9. You have all your images. It’s time for the edit. What? You can’t edit? Well that’s fine. Although again, the experts put their images through a number of processes in post production – we are keeping things simple. And what surprises most people is that there is a simple way to edit. It wont be anywhere near as good as what the experts do – in fact the experts wouldn’t really call it editing strictly. However, it works for our purposes. The secret is throwing your images into one of the applications that just auto-sequence them together. I can’t mention any of them here…but do your research.

10. I said there were ten tips….. so here is the tenth. Get your work out there, share it. Look at what others have done, join a forum, swap tips, practice, and above all…have fun getting started with time lapse photography.

About the Author
Time Lapse Systems provide Time Lapse Photography solutions for the leisure, construction and security industries. We have experience in shooting both short and long term time lapse footage and editing for use on either DVD or the Web.

via Tips For Getting Started With Time Lapse Photography – PictureCorrect.

 
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Posted by on April 25, 2011 in General, Technique, Tutes & Tips, Time Lapse, Worth a Look

 

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