Messier 51
Over the years, I have imaged the Whirlpool Galaxy (Messier 51, M51) on three separate occasions, each marking a stage in the development of my early astrophotography work. All datasets were captured using DSLR equipment, beginning with my first attempt in 2005. That initial session provided a foundational experience in long-exposure imaging—revealing the basic spiral structure of M51 despite the limitations of a beginner’s setup, modest optics, and considerable image noise.
A second series of exposures in 2008 benefited from incremental improvements in both equipment and technique. Longer integration times, refined tracking, and better calibration methods allowed for greater color fidelity and contrast, clearly distinguishing the companion galaxy NGC 5195 and the tidal bridge connecting the two systems.
The 2011 dataset represented the most refined of the three DSLR observations, achieving improved resolution and dynamic range through careful stacking and post-processing. While still constrained by the inherent sensitivity limits of DSLR sensors, this final iteration produced a noticeably smoother background and a more detailed rendition of the galaxy’s spiral arms and dust lanes.
Together, these three imaging sessions illustrate a steady progression in skill and methodology—an early chapter in a long-term pursuit of deep-sky imaging precision and aesthetic quality.
All images were calibrated and registered in DeepSkyStacker and finally processed in Pixinsight. The 2011 image was as follows:


Here is an overview of the used equipment and the exposure times:
- Date: 2011
- Location: Krefeld
- Telescope/Lense: Orion 10″ Newton
- Focal length [mm]: 1200
- Focal ratio: 4.8
- Mount: Skywatcher NEQ6
- Camera: Canon 500Da
- Autoguiding: no
- Filter: OSC
- Exposure time [min]: 363
- Resolution: 0.94″/px
And now the image from 2008:

Here is an overview of the used equipment and the exposure times:
- Date: 2008
- Location: Krefeld
- Telescope/Lense: Pentax 75
- Focal length [mm]: 500
- Focal ratio: 6.7
- Mount: Vixen GP-DX
- Camera: Canon 300Da
- Autoguiding: no
- Filter: OSC
- Exposure time [min]: 30
- Resolution: 3.04/px
And now the image from 2005:

Here is an overview of the used equipment and the exposure times:
- Date: September 2005
- Location: Krefeld
- Telescope/Lense: 8″ GSO Newton
- Focal length [mm]: 800
- Focal ratio: 4
- Mount: Vixen GP-DX
- Camera: Canon 300Da
- Autoguiding: no
- Filter: OSC
- Exposure time [min]: 20
- Resolution: 1.89″/px

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