Myth: Stacking Fixes Everything

Reality: Poor Data Remains Poor Data Stacking is one of the most powerful techniques in astrophotography. By combining multiple exposures, it improves signal quality, reduces noise, and reveals faint details that are often hidden in a single image. However, stacking cannot fix poor-quality data. If individual sub- exposures suffer from issues such as: Poor focus can occur when significant temperature changes cause the telescope’s optics to shift focus, resulting in bloated and less-defined stars.

Regular refocusing throughout the imaging session helps maintain sharp stars and preserve fine details in the final image.

Severe light pollution from cities, airports, ports, nearby artificial lights, moonlight, or low- altitude horizons can create strong gradients across the stacked image, making background correction and processing more difficult.

Cloud-contaminated images are among the worst sources of poor data. Partial cloud cover and thin high clouds can reduce contrast, distort colours, and degrade the final stacked image. Always remove cloud- affected subs before stacking.

Low-quality data can result from poor seeing, reduced transparency, humid air, haze, or even dew forming on optics.

These conditions can compromise an entire imaging session. Always monitor and predict sky conditions to maximise the quality of your data collection.

stacking will simply combine these problems together in the final stacked image.

Great astrophotography begins with collecting good data. Careful planning, accurate focusing, stable tracking, appropriate exposure settings, and favourable sky conditions are the foundation of a successful image.

Stacking reveals good data. It cannot rescue data that was never captured.