Long Exposure Tips for Astrophotography

The night sky is an exciting canvas filled with celestial wonders waiting to be marvelled at and photographed. Astrophotography — the art of photographing these wonders — allows us to gaze deeper into the cosmos and reveal details invisible to the naked eye. But astrophotography is a unique discipline, requiring specialised techniques to overcome the challenges of low-light conditions.

Long exposure is one of the most powerful tools in an astrophotographer's arsenal. By keeping the camera shutter open for extended periods, we can gather more light, revealing the faint stars, nebulae, and galaxies that would otherwise be lost in darkness. However, long exposures also introduce challenges like star trails and noise.

Ted's is passionate about helping you capture the magic of the night sky. In this blog post, we'll delve into essential long-exposure astrophotography tips to help you along.

  • Long Exposure Astrophotography Gear Checklist
  • Master these Settings for Great Astrophotography
  • Additional Astrophotography Tips
  • Products to Take You to Infinity and Beyond

Long exposure astrophotography gear checklist

Astrophotography gear

To capture the beauty of the night sky, you'll need the right tools to overcome the challenges of long exposures. Here are some essential pieces of equipment.

  • Mirrorless cameras with dedicated star modes: For astrophotography, a capable camera is crucial. Mirrorless cameras like the Nikon Z8 boast impressive low-light capabilities and features like a "Starlight mode" that optimises settings for long exposures of starry skies. Other excellent options include the Sony A7R IV, with its exceptional dynamic range, and the Canon EOS R8, with its fast and accurate autofocus.
  • Wide-angle lenses: A wide-angle lens is essential to capture the vastness of the night sky. Lenses like the Sigma 14-24mm f/2.8 Art or the Sony FE 14mm f/1.8 GM offer a broad field of view, perfect for capturing expansive starfields or the Milky Way.
  • Sturdy tripod: Camera shake is the enemy of long-exposure astrophotography. A sturdy tripod is vital to ensure your camera remains perfectly still throughout the exposure. Consider tripods with a good weight capacity to handle the weight of your camera and lens.
  • Remote shutter release: Even the slightest touch on the camera can cause vibrations during long exposures. A remote shutter release eliminates this risk, allowing you to trigger the shutter without physically touching the camera.

Master these settings for great astrophotography

Astrophotography camera settings

Once you have the right gear, it's time to dial in the perfect settings for your long exposures. Here's a breakdown of the key settings to consider.

  • Aperture: Open your aperture as wide as possible (low f-number) to gather the most light during the exposure. Lenses like the Sigma 14mm f/1.8 DG HSM Art, with its wide f/1.8 aperture, excel in low-light conditions.
  • Shutter speed: This is where the magic of long exposures happens. Experiment with different shutter speeds, starting with around 15–30 seconds and adjusting based on the desired brightness and level of star trails. Remember, longer shutter speeds will result in more prominent star trails.
  • ISO: While a higher ISO increases light sensitivity, it also introduces noise. Start with a low ISO (around 100) and adjust gradually if needed to achieve a balanced exposure without excessive noise. Cameras like the Sony A7R IV boast impressive high ISO performance, allowing you to push the limits without sacrificing image quality.
  • Manual focus: Since autofocus struggles in low light, switch to manual focus. Use the live view function on your camera screen to achieve precise focus on a bright star.

Additional astrophotography tips

Astrophotography tips

Beyond the essential gear and settings, these additional tips can help you take your astrophotography to the next level.

  • Location, location, location: Light pollution can significantly impact your results. Seek out dark locations with minimal light interference — national parks and remote areas often provide ideal conditions for capturing the night sky.
  • The 500 rule: This rule of thumb helps determine the maximum shutter speed before noticeable star trails appear. Divide 500 by the focal length of your lens to get the approximate maximum shutter speed in seconds. This is just a starting point — feel free to experiment with longer exposures for artistic effects.
  • Embrace the stacking technique: Capturing multiple long exposures and stacking them in post-processing software can significantly reduce noise and enhance image detail.
  • Foreground interest: Include a captivating foreground element — like the silhouette of a tree or a mountain — to add depth and context to your astrophotography composition.
  • Practice and experiment: As with any creative pursuit, astrophotography takes practice and experimentation. Don't be afraid to try different settings, locations, and techniques to discover what works best for you.

Products to take you to infinity and beyond

Best cameras for astrophotography

Here's a selection of the best cameras and lenses to help you capture stunning astrophotography images.

Mirrorless cameras

  • Nikon Z8 — this high-resolution mirrorless camera boasts a superb 45.7MP FX-format sensor and 8K UHD video recording. Its advanced EXPEED 7 image processor delivers lightning-fast performance, while features like a real-time viewfinder, pre-release capture, and rapid-fire autofocus make it a dream for astrophotographers.
  • Sony A7R IV — known for its impressive dynamic range and high ISO performance, the A7R IV features a 61MP back-illuminated CMOS sensor that captures stunning detail and colour. Its rugged, weather-sealed build makes it ideal for outdoor adventures.
  • Canon EOS R8 — a portable and powerful mirrorless camera offering full-frame performance in a compact, budget-friendly package. With its 24.2MP sensor, 4K60p video, and Dual Pixel CMOS AF II system, the EOS R8 is perfect for capturing stunning stills and video.

Camera lenses

  • Sigma 14-24mm f/2.8 Art — this wide-angle zoom lens is renowned for its high-quality build and optical performance. Its weather-resistant construction and premium optical design make it ideal for capturing sharp, detailed images of the night sky.
  • Sony FE 14mm f/1.8 GM — Sony's widest prime lens, the FE 14mm f/1.8 GM is perfect for landscape, architectural, and astrophotography. Its ultra-wide field of view and fast f/1.8 aperture make it exceptional for capturing expansive starfields and the Milky Way in stunning detail.