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| On top of the hill near the little town of Coldstream in the latter part of the evening. The aurora was waning, allowing me to capture a little of the Milky Way. |
WHAT IS THIS AURORA THING YOU SPEAK OF?by Rob Wagner VK3BVW
Along with my radio interests, I am also an enthusiastic photographer and the President of the Yarra Ranges Photographic Society (YRPS). The following article will appear in the Society's June newsletter. I thought there may be some readers of this blog who are also photographers, so I am also sharing a slightly edited version here. Yes, it focuses on Aurora Australis for southern hemisphere readers, but much of the information here is also applicable to northern hemisphere readers.
All the photographs featured here were taken by myself on May 11, 2024. Click on each photo for a closer view.
You may have noticed that I have included my amateur radio (a.k.a. “Ham radio”) call sign alongside my name as the author of this article. That’s because I have been an active radio operator, holding that licenced call sign for the past 44 years and being involved in radio for 56 years. That means I have seen the effects on high-frequency radio reception across six 11-year solar cycles! Geez, I’m old!
And while the recent geomagnetic solar storm decimated communications on the ham and shortwave broadcast bands for several days, the upside was we have witnessed our first serious Aurora Australis in a long time. Last month’s (May 11th) spectacular auroral activity created much excitement across the globe, with thousands of astonishing aurora images posted on social media. It was undoubtedly the best aurora I have ever seen! As another YRPS member (Greg Carrick) and I stood on Coldstream’s Boundary Road hill and looked south, I felt real awe and wonder at this fascinating natural phenomenon.
Many are disappointed when they look for aurora with their naked eyes and have difficulty seeing it. There are none of the brilliant colours that we see in photographs. However, during high levels of intensity in auroral activity, the eye can detect subtle changes of colour in the sky. On May 11, I could make out the faint pinkish glow creeping up high in the sky and the whitish bands that rested across the horizon, with occasional shafts of light shooting out.
But we live in fortunate times! The advent of digital cameras has made it possible to capture the full spectrum of auroral colours. The human eye can only grasp separate instances of colour. However, with the camera’s shutter open for an extended period, the sensor can accumulate all those instances, continuously gathering light over many seconds before forming the final image we see on the camera screen. The camera allows us to enjoy the magnificence of these coloured shapes.
Light wispy clouds and aurora smudges a part of the Milky Way.
What is this phenomenon?
The simple definition of an aurora is that it happens when charged particles are carried by solar winds and hit the earth’s atmosphere. A more detailed explanation is that auroras are brilliant ribbons of light that weave across Earth's northern and southern polar regions. These natural light shows are caused by magnetic storms triggered by solar activity, such as solar flares (explosions on the Sun) or coronal mass ejections (ejected gas bubbles). The solar wind carries energised charged particles from these events from the Sun.
When these particles seep through Earth's magnetosphere, they cause substorms. Then, fast-moving particles slam into our thin, high atmosphere, colliding with Earth's oxygen and nitrogen particles. As these air particles shed the energy they picked up from the collision, each atom starts to glow in a different colour. The Aurora Borealis (northern hemisphere) or Aurora Australis (southern hemisphere) are dynamic and visually delicate displays of solar-induced magnetic storms. They are also the first indications that our planet is under attack from a neighbouring star——the Sun. (NASA)
The solar cycle, also known as the solar magnetic activity cycle or sunspot cycle, is a periodic change in the Sun’s activity measured in terms of variations in the number of observed sunspots on the Sun’s surface. Solar cycles have an average duration of about 11 years. Solar maximum and solar minimum refer to periods of maximum and minimum sunspot counts. Cycles span from one minimum to the next. Throughout a solar cycle, levels of solar radiation and ejection of solar material, the number and size of sunspots, solar flares, and coronal loops all exhibit a synchronised fluctuation from a period of minimum activity to a period of maximum activity back to a period of minimum activity. (Wikipedia)
Auroral activity increases as we rise in the cycle, peaking and then subsiding as the cycle declines to its minimum. Right now, we are in a period of rapidly increasing solar activity, which we can expect to continue right through to a peak around the end of this year or, if we are lucky, into 2025. The decline in solar activity is far more gradual than its rise to the peak, so expect to see plenty of auroral activity over the next three to four years.
Looking south from the pony club at the end of my road in Mount Evelyn - early in the evening.
The Black Art of Auroral Forecasting
Forecasts of auroral activity are even less reliable than trying to predict the local weather! On December 30, 2015, I famously posted an Auroral Alert on our Society's Facebook page stating that there would be a spectacular auroral event that night. This alert was based on information from NOAA, the U.S.A.’s National Oceanic and Atmospheric Administration. I told the group I would head to the Kilcunda Bridge for the big event. Several YRPS members and their families came along for the adventure.
When we got there, NOTHING! Not a glimmer or a glow to be seen! And to make matters worse, we couldn’t even take any decent star shots as a wispy high-level cloud drifted in off the coast and covered the sky. We all trudged home dejectedly!
The next night, December 31, we were all out ringing in the New Year. Lady Aurora turned on a spectacular show that night, which we missed completely. Our trip to Kilcunda turned out to be a monumental Auroral Misfire! Moral of the story: Take auroral forecasting with a grain of salt! It is one of those “black arts”.
Shafts of light appeared at different times in the evening sky.
Tips for Shooting the Aurora Australis
Preparations:During periods of high solar activity, some web and media sites based in the northern hemisphere get overexcited/overly optimistic about sightings of possible auroras. Information relevant for the northern hemisphere, where populated land masses extend up to the Arctic Circle (north magnetic pole), is less useful in the southern hemisphere, where land masses are further away from the Antarctic Circle (south magnetic pole). Try the following:- https://www.spaceweatherlive.com is useful for information on current conditions and forecasts.
- The Australian Space Weather Forecasting Centre is helpful from a Southern Hemisphere perspective. (https://www.sws.bom.gov.au/Aurora).
- Smartphone apps such as Aurora Pro for iOS or equivalent apps for Android are OK, too. Some apps focus on the Northern Hemisphere and are only sometimes reliable for the Southern Hemisphere.
- The Australian Bureau of Meteorology’s Satellite Viewer page is essential for assessing cloud cover. http://satview.bom.gov.au
- There are very many active Facebook groups where enthusiasts can gather to show their photos and exchange knowledge and experiences. Search for a group in your area.
- Looking for aurora when the full moon's brightness is present can be an exercise in futility. Using your location, smartphone apps such as Moon Plus on iOS devices provide phase, rise and setting, and future dates information. It is well worth paying the small fee for the premium model app.
- Aurora and other forms of astrophotography are more successful if you can get away from city and suburban lights. Check out the Light Pollution Map for help selecting dark sky locations. https://www.lightpollutionmap.info.
- If you want to include foreground interest in your shots, scoping out potential locations during daylight hours is far easier than stumbling around in the dark.
- Make sure you understand how your camera's manual modes work and that you can find the controls in the dark (practice in a darkened room). Know your camera.
- Check your camera gear before you leave home. You can even set up some of your manual controls before you go out into the night.
Equipment- Any modern DSLR or mirrorless camera should give excellent results. You don’t need a fancy, expensive camera. Even phone cameras are pretty good, especially if you use the iOS app Slow Shutter, which allows you to dial in the duration of the open shutter.
- The lens choice is vital for capturing as much of the sky as possible. Think landscape-type lenses here. The best lens is a wide-angle (14-28mm) with the largest aperture (f/2.8 or better).
- Remember your tripod. It is an essential piece of gear when the shutter is open for many seconds. And yes, you still need a tripod or some other steady support if you are using your smartphone!
- A remote shutter release (either cable or wireless) is useful, too. But if you don’t have one, set your camera’s timer to 2 or 5 seconds.
Camera SettingsIt is difficult to recommend hard and fast camera settings. This is because auroras are constantly varying in brightness and intensity. What worked on one setting may become unsuitable five minutes later. So, it helps to alter your settings to search for the best results. Experimentation is the name of the game. However, here are some guidelines for getting started:- ISO. Start with an ISO of 600 and be prepared to work up to 3200 if necessary. Increasing the ISO allows the sensor to capture more light. However, you may not have to go that high with an aurora as intense as the one we had on May 11. That night, I was shooting between 500 and 2500 ISO.
- Aperture. Use the widest aperture on your lens (e.g., f/2.8). However, don’t be discouraged if your lens only goes down to f/3.5 or 5.6. Varying other settings in the exposure triangle can usually compensate for “slow glass.”
- Shutter Speeds. Anywhere between 5 and 30 seconds can be used here. Again, it depends on the intensity of the aurora at the time of shooting and, of course, greatly on your aperture and ISO settings. On May 11, most of my shutter speeds were between 10 and 24 seconds.
- Focus. Turn off your camera’s autofocus. It’s about as useful as an ashtray on a Harley Davidson!! Manually focus to infinity by selecting a distant object or light using Live View mode.
The pink of the aurora was so strong that it rose up from the horizon to almost overhead into the Milky Way.
Post-Processing- Lens Correction. Before editing, remember to perform a Lens Correction in Lightroom Classic. This is especially important when shooting at 14mm because lens distortion at the edges can be significant, and exposure settings can be different, too. When processing some of my May 11 shots, I forgot to make the correction at the beginning of the processing workflow. If I did the lens correction after making other setting changes, I then had to go back and readjust those settings.
- Noise Reduction. There are two aspects to noise reduction.
1) Luminance Noise comes from using high ISOs such as 3200 or greater. Cameras have improved remarkably with noise reduction over the past few years. So, this is not such an issue for some newer or more sophisticated models. For my 12-year-old Nikon D800, it is a problem. Therefore, good denoise tools are essential in your editing application of choice. But they must be used judiciously, being careful not to push the slider too far and end up with an unnatural-looking result. The recently added Denoise tool in Lightroom Classic is a killer tool!
2) Colour noise is also a problem for many cameras. Colour noise controls can quickly resolve those ugly little purple and green pixels that can be seen in dark, non-auroral parts of the sky.
- Colour Correction. Tweaking the white balance can bring out the colours you want in auroras. But don’t overdo it—a light touch is what you want on these controls.
- Sharpening. Four controls—contrast, texture, clarity, and sharpening—affect the overall sharpness of a nighttime image. Again, it is very easy to overdo these settings in post, but they will help enhance the image when used with care.
- Sky and Foreground Interest. Lightroom’s recent additions to its masking tools help process nighttime images. The “Select Sky” and “Duplicate and Invert Mask” tools make reasonably accurate selections. However, you may need to feather the selections between the horizon and the sky to achieve more masking accuracy.
Additional Thoughts- Trying to capture both the aurora and the Milky Way in the same shot can be really tricky, especially if the aurora is as intense as it was on May 11. The light was so strong that it tended to dominate the starlight (almost like shooting stars in full moonlight). On May 11, I found that my best Milky Way with aurora shots were taken when the aurora had waned a little.
- I don’t believe in being cold! Whenever I shoot at night, I wear thermals and two pairs of socks. This is probably due to poor circulation at the extremities. Remember to dress accordingly and think about layers.
Can we expect more auroras and solar storms in 2024?
The May 11 aurora was the biggest since October 2003, two decades ago! It’s impossible to know whether that’s it for Cycle 25 or if there is more to come. Space Weather Scientist at the CSIRO, Dr John Morgan, says:"No one can know for sure. The events of the last few days certainly seem to be some of the most significant of the smartphone era. It’s certainly possible that we’ve just seen the peak of auroral activity for this solar cycle. However, experience tells us that big events can happen even well after the peak of the solar cycle, so for those who missed out, there’s certainly a good chance of comparable events happening over the next few years."
My bet is that we will see more auroras in the next few years. So, it’s best to be ready to spring into action. Good luck with your aurora photography.
Rob Wagner VK3BVW
Along with my radio interests, I am also an enthusiastic photographer and the President of the Yarra Ranges Photographic Society (YRPS). The following article will appear in the Society's June newsletter. I thought there may be some readers of this blog who are also photographers, so I am also sharing a slightly edited version here. Yes, it focuses on Aurora Australis for southern hemisphere readers, but much of the information here is also applicable to northern hemisphere readers.
All the photographs featured here were taken by myself on May 11, 2024. Click on each photo for a closer view.
You may have noticed that I have included my amateur radio (a.k.a. “Ham radio”) call sign alongside my name as the author of this article. That’s because I have been an active radio operator, holding that licenced call sign for the past 44 years and being involved in radio for 56 years. That means I have seen the effects on high-frequency radio reception across six 11-year solar cycles! Geez, I’m old!
And while the recent geomagnetic solar storm decimated communications on the ham and shortwave broadcast bands for several days, the upside was we have witnessed our first serious Aurora Australis in a long time. Last month’s (May 11th) spectacular auroral activity created much excitement across the globe, with thousands of astonishing aurora images posted on social media. It was undoubtedly the best aurora I have ever seen! As another YRPS member (Greg Carrick) and I stood on Coldstream’s Boundary Road hill and looked south, I felt real awe and wonder at this fascinating natural phenomenon.
Many are disappointed when they look for aurora with their naked eyes and have difficulty seeing it. There are none of the brilliant colours that we see in photographs. However, during high levels of intensity in auroral activity, the eye can detect subtle changes of colour in the sky. On May 11, I could make out the faint pinkish glow creeping up high in the sky and the whitish bands that rested across the horizon, with occasional shafts of light shooting out.
But we live in fortunate times! The advent of digital cameras has made it possible to capture the full spectrum of auroral colours. The human eye can only grasp separate instances of colour. However, with the camera’s shutter open for an extended period, the sensor can accumulate all those instances, continuously gathering light over many seconds before forming the final image we see on the camera screen. The camera allows us to enjoy the magnificence of these coloured shapes.
 |
| Light wispy clouds and aurora smudges a part of the Milky Way. |
What is this phenomenon?
The simple definition of an aurora is that it happens when charged particles are carried by solar winds and hit the earth’s atmosphere. A more detailed explanation is that auroras are brilliant ribbons of light that weave across Earth's northern and southern polar regions. These natural light shows are caused by magnetic storms triggered by solar activity, such as solar flares (explosions on the Sun) or coronal mass ejections (ejected gas bubbles). The solar wind carries energised charged particles from these events from the Sun.
When these particles seep through Earth's magnetosphere, they cause substorms. Then, fast-moving particles slam into our thin, high atmosphere, colliding with Earth's oxygen and nitrogen particles. As these air particles shed the energy they picked up from the collision, each atom starts to glow in a different colour. The Aurora Borealis (northern hemisphere) or Aurora Australis (southern hemisphere) are dynamic and visually delicate displays of solar-induced magnetic storms. They are also the first indications that our planet is under attack from a neighbouring star——the Sun. (NASA)
The solar cycle, also known as the solar magnetic activity cycle or sunspot cycle, is a periodic change in the Sun’s activity measured in terms of variations in the number of observed sunspots on the Sun’s surface. Solar cycles have an average duration of about 11 years. Solar maximum and solar minimum refer to periods of maximum and minimum sunspot counts. Cycles span from one minimum to the next. Throughout a solar cycle, levels of solar radiation and ejection of solar material, the number and size of sunspots, solar flares, and coronal loops all exhibit a synchronised fluctuation from a period of minimum activity to a period of maximum activity back to a period of minimum activity. (Wikipedia)
Auroral activity increases as we rise in the cycle, peaking and then subsiding as the cycle declines to its minimum. Right now, we are in a period of rapidly increasing solar activity, which we can expect to continue right through to a peak around the end of this year or, if we are lucky, into 2025. The decline in solar activity is far more gradual than its rise to the peak, so expect to see plenty of auroral activity over the next three to four years.
 |
| Looking south from the pony club at the end of my road in Mount Evelyn - early in the evening. |
The Black Art of Auroral Forecasting
Forecasts of auroral activity are even less reliable than trying to predict the local weather! On December 30, 2015, I famously posted an Auroral Alert on our Society's Facebook page stating that there would be a spectacular auroral event that night. This alert was based on information from NOAA, the U.S.A.’s National Oceanic and Atmospheric Administration. I told the group I would head to the Kilcunda Bridge for the big event. Several YRPS members and their families came along for the adventure.
When we got there, NOTHING! Not a glimmer or a glow to be seen! And to make matters worse, we couldn’t even take any decent star shots as a wispy high-level cloud drifted in off the coast and covered the sky. We all trudged home dejectedly!
The next night, December 31, we were all out ringing in the New Year. Lady Aurora turned on a spectacular show that night, which we missed completely. Our trip to Kilcunda turned out to be a monumental Auroral Misfire! Moral of the story: Take auroral forecasting with a grain of salt! It is one of those “black arts”.
 |
| Shafts of light appeared at different times in the evening sky. |
Tips for Shooting the Aurora Australis
Preparations:
During periods of high solar activity, some web and media sites based in the northern hemisphere get overexcited/overly optimistic about sightings of possible auroras. Information relevant for the northern hemisphere, where populated land masses extend up to the Arctic Circle (north magnetic pole), is less useful in the southern hemisphere, where land masses are further away from the Antarctic Circle (south magnetic pole).
Try the following:
- https://www.spaceweatherlive.com is useful for information on current conditions and forecasts.
- The Australian Space Weather Forecasting Centre is helpful from a Southern Hemisphere perspective. (https://www.sws.bom.gov.au/Aurora).
- Smartphone apps such as Aurora Pro for iOS or equivalent apps for Android are OK, too. Some apps focus on the Northern Hemisphere and are only sometimes reliable for the Southern Hemisphere.
- The Australian Bureau of Meteorology’s Satellite Viewer page is essential for assessing cloud cover. http://satview.bom.gov.au
- There are very many active Facebook groups where enthusiasts can gather to show their photos and exchange knowledge and experiences. Search for a group in your area.
- Looking for aurora when the full moon's brightness is present can be an exercise in futility. Using your location, smartphone apps such as Moon Plus on iOS devices provide phase, rise and setting, and future dates information. It is well worth paying the small fee for the premium model app.
- Aurora and other forms of astrophotography are more successful if you can get away from city and suburban lights. Check out the Light Pollution Map for help selecting dark sky locations. https://www.lightpollutionmap.info.
- If you want to include foreground interest in your shots, scoping out potential locations during daylight hours is far easier than stumbling around in the dark.
- Make sure you understand how your camera's manual modes work and that you can find the controls in the dark (practice in a darkened room). Know your camera.
- Check your camera gear before you leave home. You can even set up some of your manual controls before you go out into the night.
Equipment
- Any modern DSLR or mirrorless camera should give excellent results. You don’t need a fancy, expensive camera. Even phone cameras are pretty good, especially if you use the iOS app Slow Shutter, which allows you to dial in the duration of the open shutter.
- The lens choice is vital for capturing as much of the sky as possible. Think landscape-type lenses here. The best lens is a wide-angle (14-28mm) with the largest aperture (f/2.8 or better).
- Remember your tripod. It is an essential piece of gear when the shutter is open for many seconds. And yes, you still need a tripod or some other steady support if you are using your smartphone!
- A remote shutter release (either cable or wireless) is useful, too. But if you don’t have one, set your camera’s timer to 2 or 5 seconds.
Camera Settings
It is difficult to recommend hard and fast camera settings. This is because auroras are constantly varying in brightness and intensity. What worked on one setting may become unsuitable five minutes later. So, it helps to alter your settings to search for the best results. Experimentation is the name of the game. However, here are some guidelines for getting started:
- ISO. Start with an ISO of 600 and be prepared to work up to 3200 if necessary. Increasing the ISO allows the sensor to capture more light. However, you may not have to go that high with an aurora as intense as the one we had on May 11. That night, I was shooting between 500 and 2500 ISO.
- Aperture. Use the widest aperture on your lens (e.g., f/2.8). However, don’t be discouraged if your lens only goes down to f/3.5 or 5.6. Varying other settings in the exposure triangle can usually compensate for “slow glass.”
- Shutter Speeds. Anywhere between 5 and 30 seconds can be used here. Again, it depends on the intensity of the aurora at the time of shooting and, of course, greatly on your aperture and ISO settings. On May 11, most of my shutter speeds were between 10 and 24 seconds.
- Focus. Turn off your camera’s autofocus. It’s about as useful as an ashtray on a Harley Davidson!! Manually focus to infinity by selecting a distant object or light using Live View mode.
 |
| The pink of the aurora was so strong that it rose up from the horizon to almost overhead into the Milky Way. |
Post-Processing
- Lens Correction. Before editing, remember to perform a Lens Correction in Lightroom Classic. This is especially important when shooting at 14mm because lens distortion at the edges can be significant, and exposure settings can be different, too. When processing some of my May 11 shots, I forgot to make the correction at the beginning of the processing workflow. If I did the lens correction after making other setting changes, I then had to go back and readjust those settings.
- Noise Reduction. There are two aspects to noise reduction. 1) Luminance Noise comes from using high ISOs such as 3200 or greater. Cameras have improved remarkably with noise reduction over the past few years. So, this is not such an issue for some newer or more sophisticated models. For my 12-year-old Nikon D800, it is a problem. Therefore, good denoise tools are essential in your editing application of choice. But they must be used judiciously, being careful not to push the slider too far and end up with an unnatural-looking result. The recently added Denoise tool in Lightroom Classic is a killer tool! 2) Colour noise is also a problem for many cameras. Colour noise controls can quickly resolve those ugly little purple and green pixels that can be seen in dark, non-auroral parts of the sky.
- Colour Correction. Tweaking the white balance can bring out the colours you want in auroras. But don’t overdo it—a light touch is what you want on these controls.
- Sharpening. Four controls—contrast, texture, clarity, and sharpening—affect the overall sharpness of a nighttime image. Again, it is very easy to overdo these settings in post, but they will help enhance the image when used with care.
- Sky and Foreground Interest. Lightroom’s recent additions to its masking tools help process nighttime images. The “Select Sky” and “Duplicate and Invert Mask” tools make reasonably accurate selections. However, you may need to feather the selections between the horizon and the sky to achieve more masking accuracy.
Additional Thoughts
- Trying to capture both the aurora and the Milky Way in the same shot can be really tricky, especially if the aurora is as intense as it was on May 11. The light was so strong that it tended to dominate the starlight (almost like shooting stars in full moonlight). On May 11, I found that my best Milky Way with aurora shots were taken when the aurora had waned a little.
- I don’t believe in being cold! Whenever I shoot at night, I wear thermals and two pairs of socks. This is probably due to poor circulation at the extremities. Remember to dress accordingly and think about layers.
Can we expect more auroras and solar storms in 2024?
The May 11 aurora was the biggest since October 2003, two decades ago! It’s impossible to know whether that’s it for Cycle 25 or if there is more to come. Space Weather Scientist at the CSIRO, Dr John Morgan, says:
"No one can know for sure. The events of the last few days certainly seem to be some of the most significant of the smartphone era. It’s certainly possible that we’ve just seen the peak of auroral activity for this solar cycle. However, experience tells us that big events can happen even well after the peak of the solar cycle, so for those who missed out, there’s certainly a good chance of comparable events happening over the next few years."
My bet is that we will see more auroras in the next few years. So, it’s best to be ready to spring into action. Good luck with your aurora photography.
Rob Wagner VK3BVW
CLICK HERE for VK3BVW Live Stream (Clublog)
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© Rob Wagner, Mount Evelyn DX Report, and contributors 2012-2024
Thanks. Great article.
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