Astrophotography

original
Stacked
In 2026, I undertook an astrophotography course for my Master of Science (Astronomy) at Swinburne University of Technology. My project sought to:
  • Compare the impact of location (urban, suburban, and rural) and processing techniques on image quality
  • Understand how different cameras and lenses (Canon 5D Mark III, 650D, and Samsung Galaxy Z Fold 5) perform in these environments
  • Image three target constellations (Orion, Canis Major, and Crux) for direct comparisons between these variables and each other.

This project involved learning the pre- and post-processing workflow in Siril. You can inspect some of my favourite stacks from this project below.

If you'd like to look at comparisons outlined in the report, jump to Urban, Suburban, Rural, or Extra Content.

Urban

Camera Comparison
Camera comparison images of Canis Major captured in an urban environment, progressively cropped to highlight detail. All shots taken between 8pm and 8.10pm in Footscray Park on Night 6. From left to right: 5D (50mm, ISO 100, f/1.8, 4”), 650D (18mm, ISO 400, f/3.5, 2”), ZF5 (24mm ISO 500, f/1.8, 4” total integration time)

Processing Comparison

Out-of-camera image of Crux, captured with a Canon 5D Mark III in Footscray on Night 6. 50mm, ISO 100, f/1.8, 4".
Lightroom-adjusted image of Crux, captured with a Canon 5D Mark III in Footscray on Night 6. 50mm, ISO 100, f/1.8, 4".
Out-of-camera image of Crux, captured with a Canon 5D Mark III in Footscray on Night 6. 50mm, ISO 100, f/1.8, 4".
Stacked image of Crux, captured with a Canon 5D Mark III in Footscray on Night 6. 96" integration time with subframes at 50mm, ISO 100, f/1.8, 4".
Stacked image of Crux, captured with a Canon 5D Mark III in Footscray on Night 6. 96" integration time with subframes at 50mm, ISO 100, f/1.8, 4".
Comparison of processing pipelines for Crux, captured with the 5D on Night 6. Light frames are ISO 100, f/1.8, 4”, with 96” integration time in the stack. From left to right: single-shot out-of-camera, single-shot adjusted in Lightroom Classic, and fully stacked and processed sequence in Siril, with final adjustments in Photoshop.

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Suburban

Camera Comparison
Out of camera comparisons of Orion captured on Night 7. From top to bottom: 5D (ISO 1600, f/1.8, 2”), 650D @ 50mm (ISO 1600, f/5, 2”), ZF5 (ISO 400, 13” total integration time).

Processing Comparison
Processing results for Canis Major on Night 7. Left to right: Out of camera; adjusted in Lightroom; processed, stacked, and stretched in Siril, with 126 seconds integration time across 63 light frames. Frames from 5D with ISO 1600, f/1.8, 2”.

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Rural

Camera Comparison
Camera comparisons for Crux on Night 4. Left to right: 5D (ISO 400, f/1.8, 20”), 650D (20mm, ISO 3200, f/3.5, 6”), ZF5 (ISO 1600, f/1.8, 24.5”)

Processing Comparison
Wide field 650D images of Crux on Night 4. Left to right: Out of camera, adjusted in Lightroom, processed and edited stack with 42" integration from 31 light frames. All frames captured at 18mm, ISO 3200, f/3.5, 2"

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Extra Content

Sources of errors
Cropped images from across the observing sessions demonstrating errors found in this report. From left to right: Passing objects (in this case, a plane), wrongly shaped stars (in this case, arrows), and astigmatism (caused by optical aberrations).

Light pollution
Light pollution, especially in urban settings, was a key driver for the comparative analysis in this report. Overall sky brightness in urban settings affects both single frames (left) and stacked frames (middle). While this form of light pollution was largely absent in rural settings, trespass light—where out-of-frame, local light sources flare onto the image—was a problem in all settings, particularly with the wide focal length of the Z Fold 5.

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Before and after

Original
Stacked
Before and after images of Canis Major, captured at Parkdale on Night 7. Original frame is ISO 1600, f/1.8, 2". Stacked image is from 126" integration using Siril's background extraction and the VeraLux HyperMetric Stretch Python script.
original
Stacked
Before and after images of Orion, captured at Lake Bolac on Night 4. Original frame is ISO 400, f/1.8, 10". Stacked image is from 90" integration using Siril's background extraction and Generalised Hyperbolic Stretch.
Stacked image of Crux, captured with a Canon 5D Mark III in Footscray on Night 6. 96
original
Stacked
Before and after images of Crux, captured at Footscray Park on Night 6. Original frame is ISO 100, f/1.8, 4". Stacked image is from 90" integration using Siril's background extraction and Generalised Hyperbolic Stretch.