Congratulations to Denver Astronomical Society member Leah Theil, who earned recognition in two categories of the prestigious Williamina Fleming Imaging Award Contest. Leah has been named Runner-Up in the Solar System Imaging (>500 mm) category and Third Place in the Rich Field Imaging (201–500 mm) category, an impressive achievement that showcases both her technical skill and artistic eye.
From First Dark Sky to Award-Winning Images
Leah has been a member of the Denver Astronomical Society since 2022, but her astrophotography journey began several years earlier.
“I started with astrophotography in 2016 after visiting a dark site for the very first time where I was able to see the Milky Way with just my eyes. From then on I had an uncontrollable urge to take images of the night sky.”
Like many astrophotographers, Leah faced a steep learning curve when she first began imaging. Seeking guidance and community, she joined DAS and became involved with the Astrophotography Special Interest Group (ASIG). Through ASIG meetings, training from noted astrophotographer Adam Block, and encouragement from fellow DAS members, she steadily refined her skills and eventually became confident enough to share her work publicly.
A Passion for Wide-Field Imaging
While Leah has experience with a variety of imaging targets, she is particularly drawn to wide-field astrophotography.
“I’m most interested in wide-field astrophotography because the imaging equipment is easier to move and more forgiving. I’m also too lazy to waste one of the few clear nights I have fighting with my equipment.”
That practical approach has clearly paid off, resulting in images that stood out among entries from talented astrophotographers across the country.
Third Place: Heart Nebula (IC 1805)
Leah’s award-winning image of the Heart Nebula (IC 1805) earned Third Place in the Rich Field Imaging (201–500 mm) category.
The Heart Nebula is a large emission nebula located approximately 7,500 light-years away in the constellation Cassiopeia. Its glowing clouds of ionized hydrogen form a distinctive heart-shaped structure that makes it a favorite target for deep-sky imagers.
The image was captured from Leah’s home in Thornton, Colorado, under Bortle 8 skies on October 19, 2025. Using narrowband SHO imaging, she collected:
- 48 exposures of 120 seconds in Hydrogen-Alpha (Ha)
- 23 exposures of 120 seconds in Oxygen-III (OIII)
- 23 exposures of 120 seconds in Sulfur-II (SII)
The image was processed using PixInsight and captured with:
- QHY Minicam 8 Mono
- Askar SQA55 astrograph
- ZWO AM5 mount
The entire imaging session was run automatically using the NINA Advanced Sequencer, demonstrating how modern imaging software can help astrophotographers maximize valuable clear-sky opportunities.
Runner-Up: 2024 Total Solar Eclipse
Leah’s stunning image of the April 8, 2024 Total Solar Eclipse earned Runner-Up in the Solar System Imaging (>500 mm) category.
Captured from Ravenna, Texas, during totality, the image reveals the Sun’s delicate outer corona extending far into space. Remarkably, the image was presented exactly as captured.
“This image is unedited, it was captured using the NINA Advanced Sequencer to take a range of exposures with different settings during totality.”
The image was taken with:
- William Optics Zenithstar 61II (61 mm aperture, 360 mm focal length)
- Canon EOS RP
- ZWO AM5 mount
Only a single exposure of 0.25 seconds was required to create the award-winning image.
The Value of Community
Leah’s success highlights one of the greatest strengths of the Denver Astronomical Society: the opportunity to learn from and grow alongside fellow enthusiasts. Through participation in DAS and ASIG, she found the support, education, and encouragement needed to advance her astrophotography skills from beginner to national recognition.
We congratulate Leah on her achievements in the Williamina Fleming Imaging Award Contest and look forward to seeing what she captures next.
