Tag Archives: Astro Image Processing

How to capture Deep-Space Objects with Breathtaking Landscapes

For decades, astrophotography was split into two camps. On one side, you had the landscape photographers capturing the Milky Way arching over a lonely pine tree with a wide-angle lens. On the other hand, you had the deep-space specialists – the “faint photon hunters” – who used massive telescopes to track nebulae and galaxies from their backyards. But recently, a new discipline has emerged that bridges the two: The Deepscape.

A deepscape is a photograph that pairs a distant, high-detail deep-space object (DSO) – like the Orion Nebula, the Andromeda Galaxy, or the Pleiades – with a terrestrial foreground. It is the “final boss” of night photography. It requires the precision of an astronomer and the eye of a landscape artist.

Here is your comprehensive guide to capturing the universe without losing the Earth.

1. The Gear: Moving Beyond the Tripod

When you’re shooting at 14mm, the Earth’s rotation is a minor nuisance. When you’re zooming into a nebula at 200mm or 400mm, the Earth’s rotation is a violent blur. To bridge this gap, your gear list needs an upgrade.

The Equatorial Mount

This is the most critical piece of kit. An equatorial mount (or star tracker) compensates for the Earth’s rotation by moving the camera at the exact same speed as the stars. Without this, your stars will trail in seconds.

The Lens Choice

Forget the wide-angle glass. For deepscapes, you want telephoto lenses.

-> 70-200mm: Perfect for large targets like the Orion Molecular Cloud or the Andromeda Galaxy.

-> 300-500mm: Ideal for smaller nebulae or “compressing” the moon/planets against distant mountains.

The Camera

While a standard DSLR or mirrorless camera works, astromodified cameras are the gold standard. These have the internal IR-cut filter removed to allow the deep red light of Hydrogen-alpha (H\alpha)—the stuff nebulae are made of—to reach the sensor.

2. The Planning: Aligning the Heavens

You can’t just show up and hope for the best. Deepscapes require “celestial alignment”. You need to know exactly where a galaxy will set behind a specific mountain peak.

Essential Tools

PhotoPills or Stellarium: These apps allow you to simulate the night sky at any date and location. You can use the “Night Augmented Reality” mode to see exactly where the Lagoon Nebula will be at 3:00 AM.

The Bortle Scale: You need dark skies. Aim for a Bortle 1-3 location. In a Bortle 8 city, the faint dust of a nebula will be drowned out by the orange glow of streetlights.

The Moon Phase

Unlike wide-field photography where a little moonlight can illuminate the landscape, deep-space objects are easily washed out. Schedule your shoot during the New Moon phase or after the moon has set.

3. The Technical Execution: A Tale of Two Exposures

Because you are using a tracker, you face a physical paradox: if the camera moves to follow the stars, the ground will be blurred. If the camera stays still for the ground, the stars will trail.

The solution? The Composite Method.

Step A: The Sky Frames (Tracked)

Once your mount is polar-aligned, take multiple long exposures of your chosen DSO.

Settings: f/2.8 or f/4, ISO 800-1600, and exposure times of 60–120 seconds.

Stacking: Don’t just take one photo. Take 20 or 30. By “stacking” these images in software, you improve the Signal-to-Noise Ratio (SNR).

You’ll have to try this multiple times in order to find the perfect exposure balance and optimise SNR.

Step B: The Foreground Frames (Untracked)

Turn off your tracker. You need a rock-solid, sharp landscape.

Blue Hour Secret: The best deepscapes often use foregrounds shot during “Blue Hour” (just after sunset or before sunrise). This allows you to capture detail, texture, and colour in the landscape that is impossible to get in pitch blackness.

Long Exposure: If you must shoot at night, take a 5–10 minute exposure at a lower ISO to keep the foreground clean.

Having experience with landscape photography helps a bunch here, and you can practise this a bunch in daylight.

4. The Challenges of Long Focal Lengths

As you increase your focal length, two enemies emerge: Atmospheric Turbulence and Flexure.

Seeing Conditions: On hot nights, the heat rising from the ground creates “shimmering” (atmospheric seeing). This ruins deep-space detail. Aim for cold, stable nights. You can mitigate this by researching the place and weather conditions to make sure the temperature is low and winds are calm.

Wind: At 400mm, a light breeze acts like an earthquake. Use a heavy-duty tripod and hang your gear bag from the centre column for stability.

5. Post-Processing: Bringing the Nebula to Life

This is where the magic (and the hard work) happens. You will likely use software like Adobe Photoshop, PixInsight, or DeepSkyStacker.

The Masking Process

You must carefully mask the tracked sky and blend it with the static foreground. The goal is “believable transitions”. If you see a hard, glowing line around the mountain, the illusion is broken. Use a soft brush and match the colour temperature of the sky’s glow to the light hitting the landscape.

Colour Balancing

Deep space isn’t just black. It’s filled with colourful gases.

Oxygen III: Blue/Green

Hydrogen Alpha: Deep Red

Sulfur II: Deep Orange/Red

Avoid over-saturating. The most breathtaking deepscapes feel like a window into a reality we can’t see with the naked eye, rather than a neon light show.

6. The Ethics of “Faking It”

There is a healthy debate in the community about deepscapes. Is it “real”?

The Rule of Realism: Most pro photographers insist that the DSO must have actually been in that position at that time. Taking a photo of the Andromeda Galaxy in the North and pasting it over a South-facing mountain is generally considered a “digital art piece” rather than a photograph.

The Focal Length Match: Ensure your foreground and sky are shot at the same focal length. If you shoot a mountain at 35mm and a nebula at 400mm and combine them, the scale will look “uncanny” and wrong to the human eye.

Final Say

Capturing a deepscape is an exercise in patience. It is a hobby of failures—forgotten batteries, foggy lenses, and alignment errors—which is bread & butter for landscape and astrophotography—and the only thing you can do to avoid mishaps is practice.

But when you finally align your tracker, wait out the cold, and see the spiral arms of a galaxy hovering over a familiar mountain range, the perspective shift is profound. You aren’t just taking a picture of a rock; you’re capturing the Earth’s place in an infinite, glowing neighbourhood, now frozen in time.

Astronomical Events in 2026 & How to Photograph Them

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The night sky is a dynamic arena, a celestial ballet that has captivated humanity since we first looked upward. While every year offers its share of planetary alignments and meteor showers, some years stand out for hosting truly spectacular, once-in-a-lifetime astronomical phenomena. The year 2026 is poised to be one such year, offering enthusiastic amateurs to seasoned professional photographers incredible opportunities to capture the cosmos.

However, the modern world presents a significant hurdle to astrophotography: light pollution. The encroaching glow of urban sprawl has washed out the heavens for much of the global population. Therefore, planning for the events of 2026 isn’t just about knowing when to look, but where to look. This guide explores the key astronomical events of the upcoming year and weaves in essential techniques for capturing them, emphasising the crucial role of certified Dark Sky locations in achieving breathtaking results.

The Foundation: Seeking True Darkness

Before diving into specific dates, it is essential to establish the importance of location. You cannot photograph faint celestial objects if the atmosphere is glowing with artificial light. For the best possible imagery in 2026, you must seek out true darkness.

This is where International Dark Sky Reserves play a pivotal role. Designated by DarkSky International (formerly the IDA), these are regions surrounded by populated areas that possess an exceptional quality of starry nights and a nocturnal environment that is specifically protected for its scientific, natural, educational, and cultural value.

Visiting a Dark Sky Reserve—such as Aoraki Mackenzie in New Zealand, NamibRand in Namibia, or regions in the American Southwest and rural Europe—does more than just let you see more stars with the naked eye. For a camera sensor, it means a significantly better signal-to-noise ratio. The absence of artificial light allows you to use higher ISO settings and longer exposures without washing out the image frame with orange or grey haze. When planning your 2026 celestial travels, prioritising proximity to a Dark Sky Reserve will exponentially improve your photographic output, especially for faint targets like meteors or the Milky Way’s galactic core.

The Main Event: The Great European Total Solar Eclipse (August 12, 2026)

Without question, the anchor event of 2026 is the total solar eclipse on August 12th. While total eclipses happen somewhere on Earth roughly every 18 months, they often occur over inaccessible oceans or remote tundras. The 2026 path of totality is unique because it crosses highly accessible areas of the Northern Hemisphere during peak travel season, specifically touching eastern Greenland, western Iceland, and cutting a swath across northern Spain.

A total solar eclipse is perhaps the most dramatic natural event a photographer can witness. The moon completely blocks the sun’s brilliant photosphere, plunging day into an eerie twilight, dropping temperatures, and revealing the sun’s magnificent, wispy corona.

Photographing the Eclipse

Capturing an eclipse requires preparation and, crucially, safety equipment. You cannot point your camera at the sun during the partial phases without a certified solar filter; doing so will destroy your camera’s sensor and can instantly blind you if you look through an optical viewfinder.

The photographic workflow involves two distinct stages. During the partial phases, where the moon slowly takes a “bite” out of the sun, a solar filter must be on your lens. You will need a telephoto lens, ideally 400mm or longer, to get a detailed disk size. Spot metering on the sun itself will usually yield a correct exposure, resulting in an orange or white sun against a black sky.

The magic happens during the brief minutes of totality. As the final sliver of sunlight disappears—creating the brilliant “diamond ring” effect—you must swiftly remove the solar filter. This is the only time it is safe to view and photograph the sun naked. During totality, you are photographing the faint solar corona. You will need to drastically change your settings, opening your aperture and slowing your shutter speed. Because the corona’s brightness varies significantly from its inner edge to its outer wisps, the best technique is “bracketing”. Take a rapid sequence of photos at different shutter speeds (ranging from perhaps 1/1000th of a second down to 1 or 2 full seconds) to ensure you capture the full dynamic range of the sun’s atmosphere. As soon as the diamond ring reappears on the opposite side, the filter must go back on immediately.

For those targeting Spain, the eclipse occurs very late in the day, near sunset. This offers a unique, albeit challenging, photographic opportunity to capture the eclipsed sun just above the horizon, potentially incorporating landscape elements—a rare composition in eclipse photography.

The Summer Spectacle: The Perseid Meteor Shower (August 2026)

August 2026 is a powerhouse month for astronomy. Just days around the solar eclipse, the annual Perseid meteor shower will reach its peak. The Perseids are beloved for being bright, frequent, and often producing dramatic fireballs.

Crucially, the moon phase for the 2026 Perseids is incredibly favourable. Because the new moon occurs on August 12th for the eclipse, the peak nights of the Perseids (around August 12th-14th) will feature moonless skies for most of the night. This is the ideal scenario for meteor photography.

Photographing Meteors

Unlike the eclipse, which requires telephoto precision, meteor showers are about wide perspectives and patience. You need a camera with good high-ISO performance and your widest, fastest lens (ideally f/2.8 or faster).

The technique involves setting up your camera on a sturdy tripod in the darkest location you can find—again, a Dark Sky Reserve is the gold standard here. Set your lens to its widest aperture and manually focus on infinity using a bright star. Your ISO will likely need to be between 1600 and 3200, depending on your camera’s noise handling.

You want to take continuous long exposures. A typical exposure time is between 15 and 25 seconds. If you expose longer than that, the stars will begin to trail noticeably due to the Earth’s rotation (unless you are using a star tracker). Use an intervalometer (either built-in or an external remote) to lock the shutter down, taking back-to-back photos for hours.

Compositionally, while the meteors radiate from the constellation Perseus, they can appear anywhere in the sky. It is often best to compose a shot that includes an interesting foreground element—a mountain range, an interesting tree, or an old barn—and point the camera generally toward the radiant point, but including a vast expanse of sky. The goal is to capture as many frames as possible in hopes that a bright meteor streaks through one of them.

Planetary Giants: Jupiter and Saturn at Opposition

Throughout late summer and autumn of 2026, the gas giants Jupiter and Saturn will reach opposition. This means they are opposite the sun in our sky, rising at sunset, staying visible all night, and appearing at their brightest and largest for the year.

While dedicated planetary cameras and large telescopes provide the best views, impressive photographs can be taken with standard DSLR or mirrorless gear. A long telephoto lens (even a 70-200mm with a teleconverter) can resolve Jupiter as a distinct disc and easily capture its four Galilean moons as tiny pinpricks of light lined up beside it. Saturn’s rings are also resolvable with sufficient focal length.

The key challenge here is exposure. The planets are much brighter than the surrounding stars. If you expose the stars, the planets will be blown-out white blobs. You must use a fast shutter speed and low ISO, spot-metering specifically on the planet to capture surface bands on Jupiter or the definition of Saturn’s rings.

The Lunar Finale: Supermoons in 2026

While the year begins with a flurry of celestial activity, it saves a double-header of lunar brilliance for the winter months. In 2026, after the initial supermoon in January, the final two major lunar events occur back-to-back in November and December.

1. The Beaver Supermoon (November 24, 2026)

This moon marks the time of year when beavers traditionally prepare for winter. As a supermoon, it will appear roughly 14% larger and 30% brighter than a standard “micro-moon” (when the moon is at its farthest).

2. The Christmas Eve Cold Supermoon (December 24, 2026)

The final supermoon of the year is particularly poetic, occurring on Christmas Eve. Known as the Cold Moon, it will be the closest full moon of the entire year, reaching its absolute peak brightness against the crisp, clear winter sky.

How to Photograph the 2026 Supermoons

The primary challenge in supermoon photography is the sheer intensity of its light. To the naked eye, it looks massive and detailed; to a camera, it often looks like a glowing white hole in the sky. To get a professional result, you must take full control of your exposure.

The Technical Recipe

Manual Mode is Mandatory: Switch your camera to ‘M’. The moon is essentially a giant rock illuminated by direct sunlight, so it requires settings more akin to daylight photography than night photography.
Low ISO: Keep your ISO as low as possible to preserve the fine details of lunar craters and “seas” (maria).
Narrow Aperture (f/5.6 to f/11): This range is typically the “sweet spot” for lens sharpness. Using a narrower aperture also ensures that if you have distant landscape elements, they remain relatively sharp. But you can use as wide as F/5.6 to let in more light while keeping the entire moon in focus.
Fast Shutter Speeds (1/125s to 1/250s): Surprisingly, the moon moves quite fast across the sky. A common mistake is using a long exposure (e.g., 5 seconds), which results in a blurry, oblong moon. Use a fast shutter to “freeze” the moon and capture its texture.

Conclusion: Preparation Meets Opportunity

The year 2026 offers a compelling itinerary for the astrophotographer. From the high-stakes drama of the Spanish or Icelandic eclipse to the serene, all-night vigils for Perseid meteors, the opportunities are vast. Success in astrophotography, however, rarely happens by accident. It is the result of meticulous planning—scouting locations, understanding the specific phases of the event, practicing with your gear in the dark beforehand, and crucially, respecting the need for true darkness. By aligning your travel plans with certified Dark Sky locations and mastering the techniques required for these varying phenomena, you can ensure that 2026 is the year you capture the universe in all its glory.

Astrophotography featuring Historical Sites

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There is a profound, almost dizzying irony in pointing a high-tech digital sensor at a 4,000-year-old stone circle to capture light that has been traveling through the vacuum of space for millions or billions of years. When we practice astrophotography at historical sites, we aren’t just taking a “pretty picture”. We are performing a feat of cosmic archaeology. We are aligning three distinct timelines: the deep time of the universe, the ancient history of human civilization, and the fleeting millisecond of the camera’s shutter click.

For the modern photographer, these sites offer more than just a foreground; they provide a tether to our ancestors who looked at the same constellations—albeit in slightly different positions—to navigate, harvest, and worship.

The Philosophy of the Frame

Why go to the trouble of hauling thirty pounds of gear to a remote ruin in the middle of the night? Because a photo of the Milky Way over an empty field is a science experiment, but a photo of the Milky Way over the Great Sphinx of Giza is a narrative.

Historical sites provide scale and context. They remind us that while empires crumble and languages fade, the celestial dance remains the one constant. It’s a humbling reminder that we are part of a long continuum of sky-watchers. Plus, let’s be honest: a crumbling Roman aqueduct just looks significantly cooler under a canopy of stars than your backyard fence.

Technical Foundations: The Gear and the Math

Astrophotography is one of the few niches where “spraying and praying” will leave you with nothing but a black screen and a cold cup of coffee. You need a specific toolkit to bridge the gap between the dark earth and the bright stars.

The “Rule of 500”

To avoid “star trailing” (where the stars look like little sausages instead of points of light), photographers use the Rule of 500. This formula helps you calculate the maximum shutter speed before the Earth’s rotation becomes visible in your frame.

If you are using a 20mm lens on a full-frame camera (crop factor of 1), your max exposure is 25 seconds. Any longer, and those stars start to smear.

Planning: The Digital Scout

You cannot simply show up at Stonehenge and hope for the best (mostly because security will tackle you, but also because of the weather). Success in this field is 80% planning and 20% execution.

Light Pollution Maps: Use tools like Dark Site Finder to ensure the ruins aren’t drowned out by the orange glow of a nearby city.

Celestial Alignment: Apps like PhotoPills or Stellarium allow you to use Augmented Reality (AR) to see exactly where the Milky Way core or the Moon will rise relative to the monument.

Permits and Legality: This is a candid peer advice: Do not trespass. Many historical sites are protected UNESCO heritage zones. Shooting at night often requires special permission, a paid guide, or attending “Star Parties” organised by the site’s conservators.

Iconic Locations and Their Challenges

1. The Pyramids of Giza, Egypt

The ultimate prize. The challenge here isn’t just the desert heat; it’s the haze and the light pollution from nearby Cairo. To get a clear shot, photographers often have to use light pollution filters or wait for specific atmospheric conditions that clear the dust.

2. Stonehenge, United Kingdom

Stonehenge is notoriously difficult to access at night. However, the alignment of the stones with the solstices makes it a masterclass in archaeoastronomy. Capturing the North Star (Polaris) centered over a trilithon creates a “star trail” image that feels like a portal through time.

3. Moai of Easter Island (Rapa Nui)

Remote, dark, and haunting. The Moai statues offer a vertical element that perfectly complements the vertical band of the Milky Way. Because there is almost zero light pollution, you can capture the “Airglow”—a faint emission of light from the Earth’s atmosphere—that adds eerie greens and reds to your sky.

Note: When shooting at these sites, “Light Painting” (using a flashlight to illuminate the ruins) is a controversial subject. Many purists prefer using “Low Level Lighting” (LLL) or simply mask in a separate foreground exposure taken during blue hour to maintain a natural, moonlit look. You may go either way depending on the level of effort you wish to put in.

The Art of Post-Processing

The raw file coming out of your camera will likely look flat and underwhelming. The magic happens in the digital darkroom.

Stacking: Taking 10–20 identical shots and using software (like Sequator or Starry Landscape Stacker) to average out the digital noise. This makes the “sky” look silky smooth while keeping the “ruins” sharp.

Colour Balance: Ancient stones often look best with a slightly warmer tone, while the night sky usually benefits from a cooler, deeper blue. Learning to mask these two areas separately is the hallmark of a pro.

Enhancing the Nebula: Use “Dehaze” and “Clarity” sparingly on the Milky Way core to bring out the dust lanes without making the stars look like neon glitter.

Ethics: Respecting the Ancestors

Beyond the technicalities of sensors and shutters, night photography is an exercise in quiet endurance. It demands a brand of discipline that extends far beyond your gear; it is the persistence to stand in the cold for hours, waiting for a single cloud gap that may never come. We don’t just capture these scenes; we enter into a silent contract with the environment.

Leave No Trace

This philosophy is our primary directive. As temporary guests in these spaces, we must treat the landscape with profound reverence. Scaling ancient masonry or fragile rock faces for a “hero angle” is more than just reckless; it is a betrayal of the site’s history. True creative mastery is found in discovering a compelling perspective within the boundaries of respect, ensuring the location remains pristine for those who follow.

The Responsibility of Light

In a world of long exposures, our light is our footprint. While high-powered lasers are useful tools for celestial navigation, they can be remarkably intrusive. A single stray beam can ruin a fellow photographer’s twenty-minute exposure or, more critically, interfere with established flight paths—which if we might add, may land you in jail. We must manage our light with extreme caution, prioritising the “dark sky” experience for both the lens and the community.

Honouring the Midnight Sanctuary

There is a spiritual stillness that settles over a site at 3:00 AM. When the world is asleep, these locations offer a rare, raw atmosphere. Honour this by moving with intention and keeping your voice to a whisper. By embracing the silence, you aren’t just being a polite observer; you are allowing yourself to connect with the site’s true character. This connection often results in work that feels grounded, timeless, and deeply resonant.

Conclusion

Astrophotography at historical sites is more than a technical challenge; it is an act of preservation. By capturing these monuments against the backdrop of the cosmos, we document their survival through the ages. We see the handiwork of humans who are long gone, framed by the light of stars that might no longer exist. It is the ultimate long-exposure—a snapshot of our place in the universe.

Stacking Images for Noise Reduction in Astrophotography: A Complete Guide

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Astrophotography, the art of capturing the beauty of the night sky, has become increasingly popular in recent years. With the advancement of technology and the availability of high-quality cameras, it’s now possible for amateur astronomers to take stunning images of celestial objects. However, one of the biggest challenges in astrophotography is noise reduction. Noise, also known as grain or digital noise, can ruin an otherwise perfect image. In this article, we’ll explore the technique of stacking images for noise reduction in astrophotography, and provide a complete guide on how to do it.

What is Noise in Astrophotography?

Noise in astrophotography refers to the random fluctuations in pixel values that can occur due to various factors such as thermal noise, readout noise, and photon noise. These fluctuations can result in a grainy or speckled appearance in the image, which can be distracting and reduce the overall quality of the photo. Noise is more pronounced in low-light conditions, which is often the case in astrophotography.

What is Image Stacking?

Image stacking, also known as image integration or co-addition, is a technique used to reduce noise in astrophotography. The basic idea is to take multiple images of the same object, and then combine them into a single image. By doing so, the noise in each individual image is averaged out, resulting in a smoother and more detailed final image.

How Does Image Stacking Work?

When you take multiple images of the same object, the noise in each image is random and uncorrelated. By combining these images, the noise is averaged out, and the signal (the actual image data) is reinforced. This is because the noise in each image is likely to be in a different location, so when you add the images together, the noise cancels out, leaving a smoother and more detailed image.

Benefits of Image Stacking

Image stacking has several benefits in astrophotography:

Noise Reduction: The most obvious benefit of image stacking is noise reduction. By combining multiple images, you can significantly reduce the noise in the final image.
Improved Detail: Image stacking can also reveal more detail in the image, as the signal is reinforced and the noise is reduced.
Increased Dynamic Range: Image stacking can also increase the dynamic range of the image, allowing you to capture a wider range of tonal values.
Improved Colour Accuracy: By combining multiple images, you can also improve the colour accuracy of the final image.

Softwares for Image Stacking

There are several software programs available for image stacking in astrophotography. Some popular options include:

Autostakkert: A free and open-source software program specifically designed for image stacking in astrophotography.
StarStax: A free software program that allows you to stack images and also includes features such as image alignment and calibration.
Adobe Photoshop: A popular image editing software that includes features such as image stacking and noise reduction.
PixInsight: A powerful image processing software that includes features such as image stacking, noise reduction, and colour correction.

Step-by-Step Guide to Image Stacking

Here’s a step-by-step guide to image stacking in astrophotography:

Take Multiple Images: Take multiple images of the same object, using the same camera settings and exposure time.
Align the Images: Use software such as Autostakkert or StarStax to align the images, ensuring that the stars and other features are in the same location in each image.
Calibrate the Images: Calibrate the images to remove any bias or dark current noise.
Stack the Images: Use software such as Autostakkert or StarStax to stack the images, combining them into a single image.
Adjust the Settings: Adjust the settings in the software to optimise the stacking process, such as the number of images to stack and the alignment method.
Save the Final Image: Save the final stacked image, which should be smoother and more detailed than the individual images.

Tips and Tricks

Here are some tips and tricks to keep in mind when image stacking in astrophotography:

Use a Tripod: Use a tripod to ensure that the camera is stable and doesn’t move between shots.
Use a Remote Shutter Release: Use a remote shutter release or the camera’s self-timer to avoid camera shake.
Take Multiple Images: Take multiple images to ensure that you have enough data to stack.
Use the same Camera Settings: Use the same camera settings and exposure time for each image.
Monitor the Weather: Monitor the weather and avoid taking images during periods of high wind or cloud cover.

Conclusion

In conclusion, image stacking is a powerful technique that allows astrophotographers to significantly reduce noise and enhance the quality of their celestial images. By combining multiple exposures, photographers can achieve smoother details, improved dynamic range, and more accurate colours, ultimately bringing out the true beauty of the night sky. With the availability of user-friendly stacking software and the right approach, even amateur astronomers can capture breathtaking images of the cosmos. Whether you’re photographing distant galaxies or the Milky Way, mastering image stacking can take your astrophotography to the next level.

Featured Image by: Kevin Francis