There haven’t been too many opportunities to photograph the comet in the first half of November owing to a bright Moon and cloudy skies. But I did get very dark skies on the evening of November 6 and shot a sequence spanning about 15 minutes near the end of twilight and when the comet dropped below the trees. The images were stacked and aligned using Siril and then finished in Lightroom/Photoshop.
Comet C/2025 A6 (Lemmon) on 06 November 2025 with a 180 mm lens.Black-and-white negative version of Comet C/2025 A6 (Lemmon) on 06 November 2025 using a 180 mm lens.
The final image was then converted to a black-and-white negative as this format can show more of the detail in the comet’s tail. It also shows more of the satellite tracks that criss-cross the sky.
It has been fun shooting this comet and now I look forward to the next photogenic comet to grace our skies.
Nikon D850, Nikon 180 mm AI-s, f/4, ISO 200, 7×120 seconds.
I have enjoyed several evenings (and one early morning) viewing and photographing Comet C/2025 A6 (Lemmon). My first sighting was the morning of 06 October 2025. By mid-October the comet had moved enough that it was visible in the evening sky.
C/2025 A6 (Lemmon) approached Earth at a distance of 0.60 AU (90 million km; 56 million mi) on 21 October 2025. It reached an apparent magnitude of 3.5 to 4.4 according to different estimates, indicating that it could be visible to the naked eye from sufficiently dark skies. During its closest approach the comet was visible in the sunset sky with a solar elongation of 42 degrees.
Here are some images and time-lapse videos of the comet.
Comet C/2025 A6 (Lemmon) in the pre dawn hours on 06 October 2025.
A time-lapse video of the comet on the same morning shows how quickly the comet moves against the background of stars in a period of one hour.
Viewing the comet in the evening was much easier.
Comet C/2025 A6 (Lemmon) in the evening hours (85 mm; 18 October 2025).
Time-lapse video of the motion of the comet (18 October 2025).
The following night I switched lenses to a medium telephoto (180mm) and was able to resolve a lot of detail in the tail of the comet.
Comet C/2025 A6 (Lemmon ) on 19 October 2025.
The next evening I went to Ashurst Lake (southeast of Flagstaff) to try and capture the comet with reflections in the water. This time I shot with a wide angle lens (35mm) to get the evening sky with the lake.
Comet C/2025 A6 (Lemmon) and Ashurst Lake. The San Francisco Peaks can be seen to the right.
A few nights later I was in Sedona and shot this image from the Cultural Park on the west side of town. There was a lot of green airglow present low in the sky. Also, the dome of light in the center of the image is from Las Vegas — 200 miles away.
Comet C/2025 A6 (Lemmon) from Sedona. (35 mm; 24 October 2025.Comet C/2025 A6 (Lemmon) from Mormon Lake overlook (180 mm, 20 October 2025).
It was time for the big lens — the Nikon 200–500mm lens at full telephoto. These were taken at Upper Lake Mary. The focus is just a bit soft owing to operator error but it still shows a lot of interesting detail in the tail.
Comet C.2025 A6 (Lemmon) on 30 October 2025.A black and white negative image of the comet. This format shows a lot of detail.
The moon is nearly full right now. I’ll wait about a week until the skies are very dark again and shoot more images of the comet before it fades away.
A previous post showed many images of Comet C/2023 A3 (Tsuchinshan-ATLAS) taken when the comet was visible in the morning sky. The comet then moved between the Earth and Sun making it difficult to see. A period of 10 days passed between my last morning images and my first evening images.
At first, the comet was difficult to see in the bright evening twilight and the presence of the Moon made it even more difficult. But each day the Moon rose later in the evening and the comet rose higher in the western sky. I was able to take advantage of clear skies and shot photographs on eight days. Here are some of the best photographs from those sessions.
13 October 2024
I had already shot images of the comet while looking to the east across Ashurst Lake when it was a morning object. Now it was time to shoot looking to the west across the Lake. The comet was very bright and easy to see. I also shot a long sequence of images to create a time-lapse video of the comet setting in the west.
Comet C/2023 A3 (Tsuchinshan-ATLAS). 13 October 2024.
Time-lapse video of the comet setting behind Ashurst Lake near Flagstaff, Arizona.
14 October 2024
The next evening I set up at the Arizona Snowbowl parking area–along with dozens of other comet watchers. It was fun to listen to folks admiring the comet and the joy from the kids when they were first able to spot it in the darkening sky. The anti tail was even easier to see on this night compared to the previous evening.
Comet C/2023 A3 (Tsuchinshan-ATLAS) from Arizona Snowbowl. 14 October 2024.
16 October 2024
The Moon was still a factor in the evenings but the comet was getting higher in the sky so it balanced out. On this evening I went to The Narrows at Upper Lake Mary since that section of the lake is oriented WSW-ENE. This meant I could photograph the comet above the water and get a reflection of it in the water. That worked out pretty well.
Comet and reflection in the still waters of Lake Mary. 16 October 2024.Comet and reflection in the still waters of Lake Mary. 16 October 2024.
20 October 2024
A few days of clouds shut me down but by this day it was very clear and the Moon was no longer a problem. I opted to use a longer telephoto (180mm) for these shots even though it might truncate part of the tail. The anti tail is still visible but is much less striking than in earlier days.
Telephoto view of the comet. 20 October 2024.
21 October 2024
The comet was continuing to rise higher in the western sky and was closer to the Milky Way so I switched back to ultra-wide angle lenses to capture both. Bonus: I was able to again capture the comet and tail reflected in the waters of Lake Mary. For the very wide image shown here I did a composite. The first image had star tracking turned on to get sharp stars and comet; the second image had tracking off to get sharp foreground. These were then combined and blended in software.
Comet and Milky Way reflected in the still waters of Lake Mary.
23 October 2024
The comet continued to climb higher, become dimmer, and have a shorter tail as it moved away from Earth and Sun. I switched to a short telephoto (85mm) to shoot a sequence of images which were then stacked to reduce image noise. I was also able to use the sequence to create a short time-lapse video to show the movement of the comet over a period of about 45 minutes.
Comet and stars using a short telephoto lens. 23 October 2024.
Time-lapse showing the motion of the comet against the background of stars. 23 October 2024.
25 October 2024
As the comet climbed higher it also was closer to the Milky Way and I again tried to get a shot with both features. This was taken with at 35mm focal length.
Comet and Milky Way. 25 October 2024.
31 October 2024
As the comet retreats it is getting smaller in the sky and it is better to use medium length telephoto lenses. Here is an image taken with the Nikkor 180mm ED AI-S lens, a legacy, manual focus lens.
Medium telephoto lens used to image the comet. 31 October 2024.
What’s next?
We are once again in a period of clouds. When skies are once again clear the comet will be much farther away, smaller, and dimmer. At this point, it will require longer exposures and bigger telephoto lenses. It should be fun!
Comet C/2023 A3 (Tsuchinshan-ATLAS) has been in the headlines and the morning sky for a few weeks. Yeah, some of the headlines and news articles are over-the-top but most of them are quite good. And the comet in the morning twilight has been fun to photograph.
Comet C/2023 A3 (Tsuchinshan-ATLAS) and Ashurst Lake, Flagstaff, Arizona.
I have taken photos on five different mornings over a nine-day period and have captured images of the comet growing brighter and the tail growing longer. On only one occasion was I able to see the comet with the unaided eye. On three occasions I was able to see it with binoculars. On all five mornings it was very easy to capture the comet with even very short exposures on the camera.
The comet is now getting very close to the Sun so I have suspended photography for a few days. When it reemerges in the evening sky I will once again start shooting photos. I hope it is easier to see during this phase.
I shot the comet with a few different focal lengths (50mm, 85mm, and180mm). I think the best images were with the 85mm f/1.8 lens (usually shot at f/2.8) as it gave a wide-enough view to include some foreground.
Here are some photographs and time-lapse video from the period 25 September through 03 October.
25 September 2024
This was my first attempt to photograph the comet. It was taken from the overlook on Mars Hill, home of Lowell Observatory, in Flagstaff. The comet is small and located in the upper middle of the photograph. I often shoot photos of astronomical objects in the eastern sky from this location because I can include much of the city.
Comet C/2023 A3 (Tsuchinshan-ATLAS) and the City of Flagstaff. (25 September 2024)
26 September 2024
I was planning on returning to Mars Hill but smoke from a managed wildfire suggested I should try elsewhere. I ended up at the Mormon Lake Overlook. The first image is a stack of 16 images taken over the course of about five minutes. The stacking increases the signal, reduces noise, and allows more stretching of the histogram to pull out the faint details.
The video was taken from the same set of images but without any cropping. The camera was mounted on a star tracker so that the comet remained fixed in the images.
A stack of 16 images taken over the course of about five minutes. (26 September 2024)
Time-lapse video of the comet rising above the eastern horizon. (26 September, 2024)
28 September 2024
With some smoke still present I returned to the Mormon Lake Overlook on this morning. I was disappointed at the clouds but afterwards decided that I really liked the image of the clouds partially obscuring the comet tail.
Clouds partially obscure the tail of the comet. (28 September 2024)
October 01 2024
I went to Ashurst Lake for this photo session with the hopes of catching a reflection of the comet tail in the calm waters of the lake. I was not disappointed!
In the first image, the comet has not risen above the horizon but the comet tail is strikingly visible in the sky and reflected in the water. In the second image, the comet has barely cleared the trees, the tail is still quite bright, but the reflection on the water has dimmed. Next, the waning crescent Moon rises–and is partially behind a cloud–as the sky brightens making the comet’s tail more difficult to see. The final image is a stack of six images and cropped to show only the comet and tail.
The tail of the comet is reflected in the still waters of Lake Ashurt, near Flagstaff, Arizona. (01 October 2024)The comet has risen above the trees and the tail remains strikingly visible while the reflection has dimmed.The crescent Moon joins the scene in the eastern twilight. The sky has brightened making it more difficult to see the tail. (01 October 2024)Close up of the comet and tail in the bright twilight. (01 October 2024)
October 03 2024
My goal on this morning was to shoot a long sequence of images so that I could produce a time-lapse video starting when the comet was below the horizon until twilight became too bright to see the comet. Again, I was at Ashurst Lake hoping for reflections or smooth water. Success!
The first image was taken ~14 minutes before the comet rose above the horizon but the tail is still easily visible.
The comet is below the horizon but the tail extends well up into the twilight sky. (03 October 2024)
Time-lapse video of the comet rising during the period 0503–0533 MST. (03 October 2024)
As I mentioned at the beginning, there have been many articles about the comet. I think this one from Sky and Telescope is one of the better ones. Also, EarthSky.org has published many beautiful photos of the comet.
There have been few opportunities for capturing night sky objects owing to clouds and the presence of the Moon. That doesn’t stop me from trying.
Comet 12P/Pons-Brooks and Triangulum Galaxy (M33).
Comet 12P/Pons-Brooks and M33 (Triangulam Galaxy).
Clouds, a bright waxing Moon, and some distant light pollution made it difficult to capture this comet. This was taken at the base of Arizona Snowbowl ski area at 2830 m; the elevation helps to get above some of the atmospheric haze.
Sunspots AR3615 and AR3614
Several large sunspots are visible on the face of the Sun (27 March 2024).
Zodiacal Light
Zodiacal light, Jupiter, and Comet 12P/Pons-Brooks (28 March 2024).
While setting up to photograph a launch at Vandenberg SFB (which was scrubbed), I fired off a few test shots of the zodiacal light. In review, I noticed that I also captured Comet 12P/Pons-Brooks. Small–very small–when shot with a 24mm wide-angle lens.
Now, the Moon is out of the way and the forecast indicates a few clear nights so maybe I’ll get another change to shoot some images of the comet.
