Wednesday, 28 February 2018
How I Created a 16-Gigapixel Photo of Quito, Ecuador
A few years ago, I flew out to Ecuador to create a high-resolution image of the capital city of Quito. The final image turned out to be 16 gigapixels in size and at a printed size of over 25 meters (~82 feet), it allows people see jaw-dropping detail even when viewed from a few inches away.
I’ve always thought that gigapixel technology was amazing since I first saw it around 8 or 9 years ago. It combines everything that I like about photography: the adventure of trying to capture a complex image in challenging conditions as well as using high tech equipment, powerful computers, and advanced image processing software to create the final image.
I’ve been doing this for a while now, so I thought that I would share some of my experiences with you all so that you can make your own incredible gigapixel image as well.
The Gist
The picture was made with the 50-megapixel Canon 5DSR and a 100-400mm lens. It consists of 912 photos with each one having a .RAW file size of over 60MB. To create the image a robotic camera mount was used to capture over 900 images with a Canon 5DSR and 400mm lens. Digital stitching software was then used to combine them into a uniform high-resolution picture.
With a resolution of 300,000×55,313 pixels, the picture is the highest resolution photo of Quito ever taken. This allows you instantly view and explore high-resolution images that are over several gigabytes in size.
Site Selection
The first step in taking the photo is site selection. I went around Quito and viewed several different sites. Some the sites I felt were too low to the ground and didn’t give the wide enough panorama that I was looking for. Other sites were difficult to access or were high up but still not able to give the wide panoramic view that I was looking for.
I finally settled on taking the image from near the top of the Pichincha Volcano. Pichincha is classified as a stratovolcano and its peak is over 15,000ft high. I was to access the spot via a cable car and it gave a huge panoramic vista of the entire city as well as all the volcanoes that surround Quito.
The only drawback that I saw to the site is that I felt that it was a little too far away from the city and I didn’t think that people would be able to see any detail in the city when they zoomed in. To fix this situation I decided to choose a site a bit further down from the visitor center. That meant that we would have to carry all there equipment there (which isn’t easy at high altitudes) but I felt that it would give the best combination of a great panoramic view and be close enough to the city for detail to be captured.
The Setup
The site was surrounded by very tall grass as well as a little bit of a hill that could block the complete view so I decided to set up three levels of scaffolding and shoot from the top of that. There wasn’t any power at the site since it was on the side of a volcano so we had to bring a small generator with us.
I ran extension cords from the generator up to the top of the scaffolding where it powered the panorama head, as well as my computer. I didn’t plug in the camera in because I would be able to easily change the batteries if they ran out.
Atmospheric Conditions
Anything that affects the light rays on their path to the camera’s sensor will affect the ultimate sharpness of the image. Something that is rarely mentioned is the effects of the atmosphere on high-resolution photos. Two factors are used to define atmospheric conditions: seeing and visibility.
Seeing is the term astronomers use to describe the sky’s atmospheric conditions. The atmosphere is in continual motion due to changing temperatures, air currents, weather fronts and dust particles. These factors are what cause the star images to twinkle. If the stars are twinkling considerably we have “poor” seeing conditions and when the star images are steady we have “good” seeing conditions.
Have you ever seen a quarter lying on the bottom of a swimming pool? The movement of the water makes it look like the quarter is moving around and maybe a little bit blurry. Just as the movement of water moves an image, atmospheric currents can blur a terrestrial image. These effects can be seen in terrestrial photography as the mirage effect, which is caused by heat currents and also as a wavy image due to windy conditions. It’s interesting to note that seeing can be categorized according to the Antoniadi scale.
The scale is a five-point system, with 1 being the best seeing conditions and 5 being the worst. The actual definitions are as follows:
- Perfect seeing, without a quiver.
- Slight quivering of the image with moments of calm lasting several seconds.
- Moderate seeing with larger air tremors that blur the image.
- Poor seeing, constant troublesome undulations of the image.
- Very bad seeing, hardly stable enough to allow a rough sketch to be made.
(Note that the scale is usually indicated by use of a Roman numeral or an ordinary number.)
Visibility: The second factor that goes into atmospheric conditions is visibility, also called visible range is a measure of the distance at which an object or light can be clearly discerned. Mist, fog, haze, smoke, dust and even volcanic ash can all effect visibility.
The clear high altitude air of Quito made for some amazing visibility the day of the shoot. The only things that affected it that day were a few small grass fires in the city. The Cotopaxi volcano was also giving off smoke and ash but it didn’t seem to be a problem since it was blowing away from the city. There also weren’t any clouds in the sky which made it so that the exposure wouldn’t be affected by any clouds blocking out the sun.
Equipment
Camera: I decided to use a 50 megapixel Canon 5DS R. The 5DS R is an amazing camera that is designed without a low-pass filter which enables it to get amazing pixel-level detail and image sharpness.
Lens: A Canon 100-400mm f/5.6 II lens was used to capture the image. Several factors went into the decision to use this lens such as size, wight and focal length. The 100-400mm was small and light and would allow the robotic pano head to function with no problems. It also has a good focal length of 400mm with would allow for some nice detail to be captured.
I thought about using a 400mm DO and 400mm f/2.8 but each had its own drawbacks. The 400mm DO didn’t have a zoom and I wanted to be able to change the focal length for different types of captures if I had any problems and the 400mm f/2.8 was too big and heavy to be used properly in the pano head. I have a Canon 800mm f/5.6 which I would have loved to have used but it was also too heavy to be used with the robotic pano head (humble brag).
Another interesting factor that went into my decision to use the 100-500mm f/5.6 is that the diameter of the front lens element was small enough so that atmospheric distortion wouldn’t be too much of a problem. I have spent a lot of time experimenting with astrophotography and the larger the front lens element is the more atmospheric distortion or “mirage effect” will be picked up resulting in a blurring of the photo.
Pano Head: I used a GigaPan Epic Pro for the image capture. The GigaPan is an amazing piece of equipment which automates the image capture process. The GigaPan equipment is based on the same technology employed by the Mars Rovers, Spirit, and Opportunity, and is actually a spin-off of a research collaboration between a team of researchers at NASA and Carnegie Mellon University.
To use a GigaPan you first need to set it up for the focal length of the lens that you are using. You then tell it where the upper-left-hand corner of the image is located and where the bottom-right-hand corner of the image is. It then divides the image into a series of frames and automatically begins scanning across the scene triggering the camera at regular intervals until the scene is completely captured.
There are several other brands of panorama heads out there including Nodal Ninja and Clauss-Rodeon but I like the Gigapan the best since it is automated, simple and reliable. The GigaPan is also able to be connected to an external power source so the battery won’t run out during large image capture sequences.
Computer: I didn’t think that the memory card would be large enough for all the images to be stored on it especially since I was going to be making multiple attempts at capturing the image. I decided to shoot with the camera tethered to a MacBook Pro via Canons EOS Utility. This software not only allowed me to write the images directly to my hard drive, it also allowed me to zoom into the image in live view to get critical focus. Just in case something went wrong I simultaneously wrote the images to an external hard drive as a backup.
Camera Settings
Aperture: I set the aperture to f/8. This was done for a couple of reasons. The first was to increase the resolution of the image. Although the Canon 100-400mm f/5.6 II is a very sharp lens shooting wide open, stopping down the lens a little bit increases its sharpness. Stopping down the lens also reduces vignetting, which is a darkening of the edges and corners of the image.
Although the vignetting is minimal on the lens, I have found out that even the slightest amount of vignetting on the frame will result in dark vertical bands being shown in the final stitched image.I didn’t want to stop down the aperture too much because I was worried about diffraction reducing the resolution of the image.
Focal Length – I shot at 400mm so I could capture as much detail in the city. I could have used a 2x teleconverter but there was so much wind at the site that I was afraid that the camera would move around too much and the image would come out blurry.
ISO: I shot at an ISO of 640 due to all the wind at the site. I knew that using a high ISO would increase my shutter speed and reduce the chance of vibrations from the wind blurring the photo.
Shutter speed: All of these factors combined gave me a final shutter speed of 1/2700.
RAW: I shot in .RAW (actually .CR2) to get the maximum resolution in the photos.
Live View: I used the cameras live view function via Canons EOS Utility to raise and lock the mirror during the capture sequence. This reduced the chance of mirror slap vibrating the camera.
Gigapan Settings
The Gigapan has a lot of different settings for the capture sequence of the images. One can shoot in columns from left to right or in rows from the top down and left to right or any combination thereof. I choose to shoot the image going across in rows from top down going from left to right. Even though the image capture sequence would only take an hour or so I have found that shooting in this sequence makes for a more natural looking image in case of any change in lighting conditions. I also included a 1-second pause between the GigaPan head moving and the trigger of the camera to reduce any shake that may have been present from the pano head moving.
Image Capture
I had to go at it a few times but the final image was taken with 960 photos with each one having a .RAW file size of over 60MB.
Image Processing
Two Image Sets: Each day of the shoot presented itself with different problems. One day the city was clear but the horizon and volcanoes were obscured with clouds. On another day the horizon was totally clear. I decided to create two different image sets and combine them together to make the final image. One large image set was used for the clear sky and volcanoes another image set was used for the city.
Pre-Processing: For the horizon and volcanos I selected an image that I felt represented an average exposure of the sky into photoshop and corrected it to remove any vignetting.
For the image set of the city found an exposure of the city and color corrected and sharpened it to the way I wanted it before bringing the images into the stitching software. I recorded the image adjustments that I made and made a photoshop droplet with them. I then dragged and dropped all the files onto the droplet and let it run, automatically correcting each image of the photo sequences. It took a long time but it worked.
Autopano Giga: After the images were captured I put all of them into Autopano Giga. Autopano is a program that uses something called a scale-invariant feature transform (SIFT) algorithm to detect and describe local features in images. These features are then matched with features in other frames and the images are combined or stitched together. The software is pretty straightforward but I did a few things to make the final image.
Anti-ghosting: Autopano has something called an “anti-ghosting” which designed to avoid blending pixels that don’t match. This is useful for removing half cars or half people that could show up in the image due to the movement of objects between frames.
Exposure blending – Just in case of any vignetting or differences in the lighting I used the exposure blend function in the software to even out the exposures and make a nice blend.
.PSB: .PSB stands for Photoshop Big. The format is almost identical to Photoshop’s more common PSD format except that PSB supports significantly larger files, both in image dimension and overall size.
More specifically, PSB files can be used with images that have a height and width of up to 300,000 pixels. PSDs, on the other hand, are limited to 2 GB and image dimensions of 30,000 pixels. This 300,000-pixel limit is the reason why the final image has a 300,000-pixel width. I could have made the image a little bigger but I would have had to use a .kro format and I’m not sure that I would have been able to successfully blend the two images (one for the horizon and one for the city) together.
Computer: To stitch the .PSB together I used a laptop. I was worried that my laptop wouldn’t have enough horsepower to get the job done but it worked. The computer I used had the following specs: MacBook Pro (Retina, 15-inch, Mid 2015), 2.8 GHz Intel Core i7, 16GB 1600 Mhz DDR3, AMD Radeon R9 M370X 2048MB.
Hard Drive: The important thing to know when processing gigapixel images is that due to the large sizes of the images the processor speeds and RAM don’t really matter that much.
Since the processor cache and RAM fills up pretty quick when processing an image of that size the software directs everything to the hard drive where it creates something called a “page file” or “swap file” A page/swap file is a reserved portion of a hard disk that is used as an extension of random access memory (RAM) for data in RAM that hasn’t been used recently. By using a page/swap file, a computer can use more memory than what is physically installed in the computer. However, if the computer is low on drive space the computer can run slower because of the inability of the swap file to grow.
Since everything is happening on the hard disk it is really important to not only have a hard drive that is fast, but also one with a lot of space since it fills up really fast and won’t process the image if there isn’t enough space available since the swap file size can get gigantic. To process the Quito image I tried to use a fast PCI SSD that had around 500GB of space to process the image but the drive filled up. I took the computer back and got one with a 1TB PCI SSD and it was able to process the image.
Photoshop: I had to stitch one image for the horizon and another image for the background. Once these were done I opened them up in photoshop and used the eraser tool set to a large diameter to manually tool to manually blend them together. I then flattened the image and saved it as a .PSB file.
Image Tiling: I used a program called KRPano to make a tile of the images. If I uploaded the resulting .PSB file to the internet it would take forever for it to load up so people could see it. KRPano divides up the image into layers of small tiles. Each image you see is made up of a low-resolution tile. As you zoom into the image different small image tiles are quickly loaded and displayed with allows people to quickly view and explore the image without having to load the entire image. About 174,470 tiles were created for this image.
Image Upload
Once all the image tiles were created I compressed them into a .zip file. I felt that it would be easier to upload one large file instead of over 174,000 separate small files. The image upload went fine and I manually unzipped the image inside of the Hostgator server using FileZilla. It is good to check with the hosting company to make sure that they allow files to be unzipped inside their servers.
Website
Once the image was created, tiled and uploaded I made a simple website and embedded the .html file into an iframe so It could be displayed.
You can view the photo through an interactive viewer on Quito Gigapixel.
Closing
I hope that this little guide proves helpful for all of you. Gigapixel technology is really interesting and fun to try out. I have done quite a few gigapixel images but am by no means an expert and am always interested in learning more.
About the author: Jeff Cremer is a Lima, Peru-based photographer who works in the Amazon. You can find more of his work on Rainforest Expeditions and on Twitter and Instagram.
from PetaPixel https://petapixel.com/2018/02/28/created-16-gigapixel-photo-quito-ecuador/
This Photographer Deals with Anxiety by Creating Surreal Self-Portraits
Monica Lazăr is one of the millions upon millions of people around the world who struggles with an anxiety condition. For her, social anxiety makes it difficult to spend time with other people and causes her to become isolated. Four years ago, however, Lazăr discovered a passion for photography, and her gorgeous self-portraits have changed her life.
The Bucharest, Romania-based photographer says that her photos have given her a new way to communicate with others.
“From the beginning, photography was like the air so much-needed in those moments I felt like drowning,” Lazăr writes.
Photography also helped Lazăr find her soul mate, a man who now helps her with her self-portrait projects. He shoots the photos, and she creates the stories in them afterward in Photoshop.
“Every image is an emotion I experienced, a wish, or a fear I’m dealing with,” Lazăr says. “Self-portraits became that other dimension I can live in, and I’m grateful for this.”
“I want my work to speak about courage,” the photographer tells HuffPo. “The courage to make something beautiful out of something painful,” she said.”
You can find more of Lazăr’s work on her website, Facebook, Instagram, and 500px.
Image credits: Photographs by Monica Lazăr and used with permission
from PetaPixel https://petapixel.com/2018/02/28/photographer-deals-anxiety-creating-surreal-self-portraits/
Long Exposure Photography 101 – How to Create the Shot
It’s easy to get caught up in the fast nature of photography, technology, instant results, presets, etc. But what happens when you slow your photography right down?
This tutorial will introduce you to the 101s of daytime long exposure photography and share the exact steps you can follow to create your very own long exposure photographs.
Long exposure seascape.
What is long exposure photography?
long exposure photography can be defined in two ways. A traditional description would class it as taking photographs with the intent to deliberately capture the effect of time and display moving objects in a different way to how our eyes are used to seeing them.
But for those of a more literal-mindset, long exposure photography is a brilliant way of photographing atmospheric landscapes, whilst being able to enjoy a cup of tea and a biscuit – all at the same time.
Now, if that sounds like your type of photography, I encourage you to settle in and read on.
Slow down
The very nature of long exposure photography is pretty slow paced. It forces you to take your time, which is excellent practice for your framing and compositional skills. And because you literally can’t rush the shot, it makes you think about the light, your subject, and your compositional techniques before you invest several minutes of your time capturing the image.
It’s worth noting that there is no specific shutter speed that defines the crossover from “typical photography” to long exposure photography. It’s not the duration of your shutter speed that defines your image as a long exposure photograph. Instead, it’s your intention to capture moving objects using longer exposure times than necessary that makes it a long exposure photograph.
Generally speaking, long exposure photographs will use shutter speeds that can be measured in seconds or minutes instead of fractions of seconds.
Embrace the blur – add a sense of motion
“So, why should I take a photo using a slow shutter speed? Won’t that make it blurry?”
Yes, precisely. Using a long exposure technique is typically reserved for times when you want to selectively blur objects in your images. Common examples would be to capture flowing water, like the ocean or a waterfall. It’s also used to capture the movement of clouds or stars in the night sky.
Long exposures are great for capturing motion and stillness in a single frame.
A long exposure photograph reveals the passing of time and conveys motion in a way that your eyes are simply unable to see at the time. Long exposures turn clouds into whispers, water into silky-looking glass, and people into otherworldly ghost-like beings.
Long exposure photography allows you to capture stillness and a sense of motion in a single frame. The contrast between these elements creates a sense of mystery and adds a surreal atmosphere to your images. It’s precisely this playful mix of the fluid and the still that makes long exposure photography beautiful, strong, and mildly addictive – or maybe that’s just the cup of tea.
Anyway, here’s what you need to know to take a long exposure photograph.
Blocking out light with Neutral Density (ND) Filters
To capture those ethereal tones and silky motions in your images, you need to use a slow shutter speed. The trouble with using a slow shutter speed during the day is that it lets in a lot of light. So much light in fact, that it will inevitably overexpose your image.
To counter this, you will need to use a Neutral Density (ND) filter to make long exposure photographs during the day.
ND filters essentially sit in front of your lens and block out the light. Think of them as a fashionable set of sunglasses for your lens. And because the ND filters reduce the amount of light that hits your camera sensor, you can use shutter speeds up to several minutes long without overexposing your images – even in bright conditions.
Rectangular ND Filters – otherwise known as “rectangular dark glass to block out the light”.
Using an ND Filter
The exact length of your exposure will depend on the lighting conditions and the strength of the ND filter you use. ND filters are typically measured by the stops of light they are able to block out and are usually available in increments of 3, 6, 10, or 16-stops.
Nisi, Lee Filters, and Formatt-Hitech are among the popular brands of ND filters, although there are many others available for a variety of budgets. ND filters come in either a circular format (these screw onto the front your lens) or a rectangular format, which requires the use of an additional filter holder to mount them to your lens.
As a general rule, the more light your ND filter is able to block out, the longer your exposure will need to be to achieve a balanced exposure. And the longer your exposure, the more dramatic the effect will be in your final image.
Rectangular ND Filters attached to camera lens using a filter holder.
Don’t Move
You may be aware that when you use slow shutter speeds, the smallest bit of camera movement can throw your image out of focus and cause it to look a little blurry. This is especially true in long exposure photography.
Given that your camera will be taking several seconds or several minutes (if you’re using a 10 or 16 stop ND filter) to complete a single shot, it’s crucial to ensure it doesn’t move a millimeter during the exposure.
It would be nearly impossible to achieve this by hand. Therefore, it’s a good idea to get your hands on a sturdy tripod. This not only ensures your camera will remain still throughout the entire exposure but more importantly, it frees up your hands, so you can have a sip of your tea whilst your camera is hard at work.
In addition to your ND filters and tripod, here’s a checklist of essential equipment you’ll need for long exposure photography.
Essential Long Exposure Photography Equipment Checklist
Essential long exposure photography gear – particularly #10.
- Your ND filters.
- A sturdy tripod.
- Camera with bulb mode function – bulb mode allows you to take exposures longer than the camera’s default 30 seconds.
- Fully charged batteries – try to avoid the heart-breaking moment when your battery cuts out in the middle of an exposure.
- Lens – wide-angle lenses work very well with landscapes, seascapes, and architecture photography. If you’re just getting started, any lens that is compatible with your ND filters will work just fine.
- A shutter release cable with a locking functionality. Using a shutter release cable (remote trigger) allows you to lock the shutter open without having to touch the camera body. This reduces camera movement during your exposure.
- A viewfinder cover – during long exposures, light has a habit of finding its way into your camera through your viewfinder and ruining your images. You can prevent this from happening by using a viewfinder cover, some sticky-tac or even duct-tape.
- A dark cloth or hat – perhaps the most peculiar item on this list, however, it’s arguably one of the most important. Believe it or not, light doesn’t just find its way into your camera via the viewfinder. It also leaks in via the lens/body connection and also from the connection points on the side of your camera. Placing a dark cloth or hat over your camera works well to prevent light leaks.
- Smartphone – this will serve two purposes. First, it will help you to calculate your long exposure times via a handy long exposure calculator app that I’ll introduce you to shortly. Its second function will be to keep track of your exposure time using a simple timer.
- A flask of tea and a selection of biscuits – and you thought I was joking! By far my favorite item on the list. long exposure photography will typically have you sitting in a beautiful spot for several minutes, taking your time and soaking up your surroundings. It’s good for the soul and a creates the perfect opportunity to enjoy a well-deserved treat, particularly on cold mornings!
- Chargers, USB cables, and lens wipes. Ideal if you need to recharge your gear or remove your fingerprints from your ND filters when you’re out and about.
Every item on this list plays an important role in capturing a long exposure photograph. Now here’s precisely how you can capture one.
Step 1: Prepare at Home
Unlike a typical day of photography, long exposures don’t afford you the luxury of being able to rattle off 1,200 images in a few hours. Instead, you’re likely to return home with only a handful of good photographs after a day of long exposure photography.
So, before you grab your gear and set off in search of ethereal landscapes and mind-bending architecture, it’s well worth investing your time. Research the location and environment so you can make the most of your time in the field.
Weather Conditions
If you’re planning on shooting a landscape, cityscape, or architecture, take a look at your local weather forecast to see what the cloud cover will be like. Anything over 40% cloud cover should give you ideal conditions to capture a silky sky.
The low clouds help to create a surreal atmosphere.
Creating a long exposure seascape, on the other hand, doesn’t necessarily need a lot of cloud coverage (although, cloudy conditions over water often produce great results). It’s worth researching the water conditions because – like the clouds – the greater the movement of the water, the greater the effect of your long exposure photographs.
Cloudy and stormy conditions create dramatic long exposure photographs.
Location Scouting
Use Google Maps and street view to go for a “virtual walk” around your location. Doing so helps you to familiarize yourself with the area and scout out potential compositions for your images. Essentially, you should know precisely where you are going, how you will get there, where you will park, how much daylight you will have and in which direction you need to walk to ensure you take full advantage of your time and the conditions.
Using Google Maps and Street View can help you with composition ideas before leaving your house.
Prepare Your Equipment
There is nothing more heart-breaking than spending the time to scout out the perfect location and setting up your camera only to realize that you have left your ND filters at home or your camera battery is at 27%. Be sure to charge up all of your batteries (including your smartphone) and pack your camera bag using the equipment checklist above.
Shoot RAW
Set your camera to shoot in RAW format. Long exposures tend to have a blue or magenta color cast caused by the ND filters. Shooting in RAW allows you to easily correct the white balance in post-processing.
Ensure that your camera is set to record your images as RAW files.
Install Long Exposure Calculator Smartphone App
Spending your time trying to calculate what your exposure length should be with a 16-stop ND filter might not sound like much fun to you. Long exposure photography is all about taking time out to soak up your environment and enjoying the views – not solving algorithms.
Installing a “Long Exposure Calculator” app on your smartphone will save you time and make calculating your shutter speed much easier when you’re out in the field. Here are a couple of popular suggestions for IOS and Android users.
It’s a good idea to install the app on your smartphone at home before heading out – just in case you later find yourself in an area with no mobile coverage to download the app.
Step 2: Work the Scene
By the time you’ve prepared your gear, researched the area, and arrived at your location, you’d be forgiven for wanting to unpack and get shooting straight away. Instead, you’ll find that holding off for just a few minutes and allowing yourself to explore the scene often produces more favorable results.
Pick up your camera (without the tripod) and work the shot. Take note of the weather, light, and direction of the water, clouds, lights, or traffic. What are the characteristics of the scene? How does the mood feel? What angle best captures all of this? What are you going to include in your frame?
Step 3: Compose the Shot
Once you have decided on the perfect angle, it’s time to set up your tripod and mount your camera (without the ND filter) to compose and frame the shot. Ensure your tripod is locked in place and your camera is tightly secured. Now is also a good time to attach your remote shutter release cable to your camera.
Secure your camera to your tripod and attach the shutter release cable.
Step 4: Aperture, ISO, and Focus
Switch your camera into Aperture Priority mode and set your aperture to somewhere between f/7.1 and f/11. As a rule of thumb, this range will fall close to your lens’s sweet spot and provide you with a deep depth of field to ensure your image is sharp throughout.
As I’ve mentioned, noise and camera shake can be problematic in long exposure photography. Therefore, adjust your ISO to 100 to minimize the amount of noise and turn off Image Stabilization on your lens to reduce the amount of internal camera shake.
Aperture Priority mode, ISO 100, f/8.0
Focus your lens, ensuring your subject is sharp from back to front. When you are happy with your focus point, switch your lens over to manual focus. This essentially safeguards your focus point and prevents accidental re-focusing when you trigger the shutter.
Switch your lens over to manual focus when you’re happy with your focus point.
Step 5: Test Shot
Use your viewfinder cover (duct-tape or sticky-tac will work) to cover up your viewfinder. This will prevent light from leaking into your camera and ensure that your camera gives you an accurate metering.
Use a Viewfinder cover, duct-tape, sticky-tac or even some cardboard block out light leaks.
With your viewfinder covered and your camera still in Aperture Priority mode, take a test shot to obtain the base shutter speed. It’s the shutter speed from this test shot that will form the basis of your long exposure calculations.
It’s a good idea to review the test shot to ensure the exposure looks good and everything is perfectly in focus. When you’re happy with your test shot, check the metadata and make a mental note of the shutter speed.
Aperture Priority test shot – In this case, the camera’s light metering used a shutter speed of 1/60th. This shutter speed will form the basis of the long exposure calculations.
Step 6: Bulb Mode
Switch your camera mode from Aperture Priority to Bulb Mode and set your ISO and aperture to mirror the exact same settings as your test shot.
Bulb Mode – Set the ISO and aperture to match your test shot.
Bulb Mode allows you to keep your shutter open as long as you hold down your camera’s shutter button. However, standing next to your camera and keeping the shutter button held down with your finger isn’t ideal. Not only would this cause lots of camera shake, it would also make it nearly impossible to enjoy a cup of tea on the job (it’s clear where my priorities lie).
This is precisely why you’ll need a shutter release cable with a locking function. The lock plays the role of your finger and keeps the shutter button held down until you decide to release the lock, thus minimizing the possibility of camera shake.
Step 7: Calculate Your Long Exposure
Enter the shutter speed from your test shot into the long exposure calculator app you installed on your smartphone in step 1.
Enter the shutter speed from your test shot into your Long Exposure Calculator mobile phone app.
You will then need to set the filter density to match your ND filter. For example, if you’re planning to use a 16-stop filter, you would enter 16-stops into the app.
The app will then calculate the length of your long exposure. It’s worth noting here that this time is approximate. It doesn’t account for a change in weather conditions during the exposure or the quality of your ND filters. I use Lee Filters and from experience, I find adding approximately 25% to the app’s suggested exposure time works well.
Step 8: Set a Timer
Load your long exposure time into your smartphone’s timer. You will trigger this at the same time you commence the long exposure to keep track of timing.
With a 16-stop ND filter and a base shutter speed of 1/60th, The Long Exposure Calculator suggested that I will need an exposure time of 18 minutes. I added approximately 25% to allow for the changing light conditions and created a timer on my phone.
Step 9: ND Filters
Mount your ND filters to your camera. Be careful not to adjust the focus or zoom rings of your lens in the process. It’s a good idea to double check your lens is still set to manual focus.
Mount your ND filters to the camera.
Step 10: Mirror Lock-up
If you’re using a DSLR, enable Live View or the mirror lock-up function. These features lock your camera’s mirror in the up position, which reduces internal camera vibrations when you trigger the shutter.
Live View or the mirror lockup function will prevent camera vibration when you trigger the shutter.
Step 11: Cover the Camera
Carefully cover your camera with a dark cloth or a hat, being careful not to adjust the zoom or focus rings on your lens. This will help to prevent light from leaking into your camera during the exposure.
Perhaps the most crucial step – use a dark cloth, hat, or an old pair of trousers to wrap around your camera to prevent light leaks.
Step 12: Trigger the Shutter
Now it’s time to create your ethereal masterpiece. The aim here is to simultaneously trigger your smartphone’s timer with one hand (this will keep track of your exposure time) and with your other hand, lock the shutter release cable to hold open your camera’s shutter. If you’re like me, and the mere thought of doing two things at once confuses you, you can simply trigger them one at a time.
All that’s left for you to do at this point is make yourself comfortable and enjoy that cup of tea! Finally! And because you set a countdown timer on your smartphone, its delightful little chime will alert you when it’s time to get up to release the lock on your shutter release cable. Thereby closing the shutter and completing your long exposure photograph.
The Result
So, what do you get after spending a leisurely afternoon in front of a beautiful scene sipping from your thermos and nibbling on a cookie? Well, it’s likely you’ll return home with an image that looks something like this.
23-minute long exposure – processed in Lightroom and Photoshop.
Recap
The very nature of creating long exposure photographs is to slow down. It encourages you to step away from the rapid-fire approach and have fun creating something that you wouldn’t ordinarily be able to see. That’s what long exposure photography is all about.
By now, I’m hoping this article has you reaching for your ND filters and checking the weather forecast – I’m sure you’ll love giving it a try. In case you need a short reminder whilst you’re out in the field, here’s a snapshot of everything we’ve covered.
- Research your location, charge your gear and install the long exposure calculator app on your smartphone.
- Work the scene to find the best angle.
- Set up your tripod and compose your shot without the ND filters.
- Switch your camera to Aperture Priority mode. Set your aperture between f/7.1 – f/11.0 and your ISO to 100. Focus in on your subject and set your lens to manual focus.
- Cover your viewfinder and take a test shot.
- Switch your camera into Bulb Mode and set your aperture and ISO to match your test shot.
- Use the long exposure calculator app to calculate your exposure time.
- Set a timer on your smartphone.
- Mount your ND filters.
- Enable live view or your camera’s mirror lock-up feature.
- Cover the camera with a dark cloth or hat.
- Lock open the camera shutter and trigger your smartphone timer.
If you have any questions, please ask. And it would be great to see your long exposure photographs, so please share them in the comments below.
The post Long Exposure Photography 101 – How to Create the Shot by William Palfrey appeared first on Digital Photography School.
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