Comet Tail Growth over a Week
Unfortunately, I was only able to get to see Comet Nishimura twice before it got too close to the sun. But I thought it was interesting to see how much its tail had grown over a week!
Comet Nishimura Tail Growth
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Tag Archives: Comet
Comet Nishimura September 2
Comet Nishimura on September 2, 2023
Having learned how to process comets thanks to the excellent videos by Adam Block, I went back and finished processing my first image of Comet Nishimura from September 2, 2023. That morning we got up at 3:30 AM and drove over to Bacliff, Texas to get a good view to the East, and got set up. I found the comet, started taking pictures, and enjoyed watching the sunrise. As the sun rose over the flat water, we saw dolphins arcing out of the water – one of my favorite sights on the Texas Gulf Coast.
Because the September 2 images involved a compact comet with not much tail and a short range of locations and a rapidly brightening background, I modified the excellent instructions from Adam Block as follows:
Register and process images as normal (noting the reference image), then removing the comet using a circular mask that covered the first and last locations and PixelMath. I could get away with this because the comet didn’t have a large tail and hadn’t moved very far and there were no visible stars in the masked-out region. In this case, I integrated unweighted; if I were doing it again, I would use the weighting I determined below.
Run SubframeSelector to determine what parameter to weight the images with – PSF SNR seemed to best reflect the lower quality due to the sky brightening in the last images.
Run CometAlignment on the debayerd data to get comet-aligned images. Use PixelMath to make a mask to mask the comet core. Run StarXterminator to generate comet-only images. Integrate the images using PSF SNR weighting. Then post-process as normal. I could barely see the comet tail in these images and I tried a variety of stretches to try to pull it out. I ended up using STF and Histogram Transfer plus Curves.
Finally, put the stars image and the comet image back together using PixelMath.
Whew! Comet processing is a lot more complicated than galaxies and nebulae. Fun to see something new in the sky, though.
Camera geek info:
- Canon EOS 60D in manual mode, 60 second exposures, ISO 800
- Williams Optics Zenith Star 73 III APO telescope
- Williams Optics Flat 73A
- SkyTech 2” LPRO-MAX CCD Filter
- iOptron CEM40
- Bacliff, Texas Bortle 6 suburban skies
Frames:
- 24 60 second lights
- 30 0.03 second flats
- 30 0.03 second flat darks
- 30 60 second darks
Processing geek info:
- PixInsight
- NoiseXterminator
- StarXTerminator
Comet Nishimura with Photobomber
Comet C/2023 P1 Nishimura on September 8, 2023
Comet C/2023 P1 Nishimura with Airplane Photobomber on September 8, 2023
For the past two weekends, we’ve gotten up at 3:30 AM to drive to a spot with a long view to the East to go comet hunting. I had setup issues with my tracking mount both times – the GoTo tracking did not want to three star align. On both days, I managed to overcome that obstacle in time to capture some images of the comet. On September 8, the time frame between when the comet cleared the haze on the horizon and the time that the sky got bright pre-dawn was surprisingly short (about 20 minutes). Also on September 8, I had a funny picture where an airplane had photobombed my comet image and flew right in front of the comet.
Astrophotography is really two hobbies: capturing the images and processing them.
And I still haven’t mastered processing comets.
But thanks to the excellent videos from Adam Block and a software update on Russ Croman’s extremely useful StarXterminator program (where my Comet Nishimura data from September 2 appears in the release notes), I have finally managed to produce some decent comet pictures. I registered all the images with the one with the airplane photobomb so I could combine the final comet image with the airplane lights to make a photobomb picture.
It’s fun to find surprises in the night sky!
Camera geek info:
- Canon EOS 60D in manual mode, 30 second exposures, ISO 800 for 4 frames, ISO 400 for the remainder
- Williams Optics Zenith Star 73 III APO telescope
- Williams Optics Flat 73A
- SkyTech 2” LPRO-MAX CCD Filter
- iOptron CEM40
- Bacliff, Texas Bortle 6 suburban skies
Frames:
- 38 30 second lights, 24 used for stars
- 31 0.02 second flats
- 30 0.02 second flat darks
- 34 30 second darks
Processing geek info:
- PixInsight
- NoiseXterminator
- StarXTerminator
- Generalized Hyperbolic Stretch
Comet C2022/E3 ZTF – First View
There’s a new comet in the morning skies that hasn’t been in the inner solar system for 50K years and may not return. I got up at 4 AM on Saturday morning to try to catch it. You know I love this hobby since I got up early in the cold! It was an obvious fuzzball in a single 1 minute telescope image, but I couldn’t spot it with image stabilized binoculars. I’m hoping for more clear days as it gets closer and brighter! Have you tried to spot it?
I spent about 8 hours learning how to process comets in PixInsight and trying to get rid of the residual star trails. I’m happy with this image, but look forward to learning some more tricks to improve it!
Camera geek info:
- Canon EOS 60D in manual mode, 60 second exposure, ISO 800, custom white balance 3500K
- Williams Optics Zenith Star 73 III APO telescope
- Williams Optics Flat 73A
- iOptron CEM40
- Friendswood, Texas Bortle 7-8 suburban skies
Processing geek info:
- PixInsight
- 51 1 minute lights
- 60 1 minute darks
- 40 bias frames
- 20 flats
Throwback Thursday – Comet Hale-Bopp! April 7, 1997
I was looking through an old photo album and found a picture of Comet Hale-Bopp. I knew from the trees (and memory, actually), that it had been to the NW of my driveway. Using GoSkyWatch on my phone, I was able to determine the date the picture was taken – April 7, 1997 – by matching the comet’s position relative to the stars. Interestingly, the position in the app is not exactly where it is in the photograph, but this is the closest match. The app, by the way, gives the comet’s magnitude on that date as -1.6.
Since this is a scanned picture from film, I don’t have any camera setting or equipment info for this one. But I can tell I must have used a long exposure and a tripod from the length of the star trails.
Comet NEOWISE – Photobombers!
It’s been clear the last few nights, so I’ve been out every night to capture Comet NEOWISE as it moves across the sky. My pictures have been photobombed by an airplane (alternating red and green lights are the airplane give-away) and a satellite! My satellite tracking tool suggests the satellite photobomber was Orbiting Astronomical Observatory (OAO) 2.
Camera Geek Info (airplane photobomb, comet in upper right)
- Canon EOS 60D in manual mode set at f/5.6, 15 second exposure, ISO 1000
- Canon EF 70-300mm f/4-5.6L IS USM lens, set at 300 mm, manual focus
- Cable release
- iOptron SkyTracker with ballhead
- Tripod
Camera Geek Info (satellite photobomb, comet in-line with satellite, below and to the left)
- Canon EOS 60D in manual mode set at f/4, 6 second exposure, ISO 1000
- Canon EF 70-300mm f/4-5.6L IS USM lens, set at 70 mm, manual focus
- Cable release
- iOptron SkyTracker with ballhead
- Tripod
Comet NEOWISE – August 5, 2020
After my failed attempt earlier this week, I was ready to spot NEOWISE and knew what the surrounding star patterns looked like.
It is a much dimmer object now than it was two weeks ago, and in my camera, it no longer has a tail. But it was a good chance to test the “how dim an object can I see?” question. Fuzzy green NEOWISE is visible at magnitude 6.9; fuzzy M53 is visible at magnitude 8.3. The stars around them range from magnitude 6.1 to 9.9.
A friend suggested I look into the white balance for my astrophotography pictures, so I did a little research on good settings. The top picture used a custom white balance of 3500K. I like that the sky is blue instead of gray-pink-yellow, but I may do more experimenting to find the best color. What do you think?
Camera Geek Info (both)
- Canon EOS 60D in manual mode set at f/5.6, 2 second exposure, ISO 6400
- Canon EF 70-300mm f/4-5.6L IS USM lens, set at 300 mm, manual focus
- Cable release
- Tripod
Comet NEOWISE Failure – August 3, 2020
We’ve had a lot of rain recently, so I haven’t gotten a chance to see Comet NEOWISE in a while. It was finally clear earlier this week, so I went out for a look.
Unfortunately, I wasn’t familiar with the part of the sky it was in, so I didn’t quite get it. Lesson learned: study the sky beforehand!
Happily, it looks like the weather might cooperate this week and give me another chance.
Camera Geek Info
- Canon EOS 60D in manual mode set at f/4, 2 second exposure, ISO 3200
- Canon EF 70-300mm f/4-5.6L IS USM lens, set at 70 mm, manual focus
- Cable release
- Tripod
Comet Neowise – July 21, 2020
My husband and I drove to our favorite spot to view the horizon twice in the last two weeks to look for Comet Neowise C/2020 F3, with no luck finding it. It was too low to the horizon in the direction of the bright lights of Houston.
On our one clear night this past week, I tried to spot it from our driveway. Success! I could not spy it naked eye. With binoculars, it is a fuzzy green blob. With the camera, it has a lovely tail.
As it moves away from us, it is getting higher in the sky, but dimmer. I am looking forward to trying to spot it again the next time we don’t have clouds.
Camera Geek Info (image above)
- Canon EOS 60D in manual mode set at f/4, 4 second exposure, ISO 6400
- Canon EF 70-300mm f/4-5.6L IS USM lens, set at 70 mm, manual focus
- Cable release
- Tripod
Camera Geek Info
- Canon EOS 60D in manual mode set at f/4, 3.2 second exposure, ISO 6400
- Canon EF 70-300mm f/4-5.6L IS USM lens, set at 70 mm, manual focus
- Cable release
- Tripod
Camera Geek Info
- Canon EOS 60D in manual mode set at f/5.6, 3.2 second exposure, ISO 6400
- Canon EF 70-300mm f/4-5.6L IS USM lens, set at 300 mm, manual focus
- Cable release
- Tripod
Comet Neowise – July 10, 2020
My husband and I got up at 4:15 AM (!) on Friday to drive to our favorite spot with a good view towards the horizon to try to spot Comet Neowise C/2020 F3. We were not disappointed! While not naked eye visible, the comet and its tail were easily visible in binoculars and through the camera lens. We enjoyed a good look at it and the planets – Venus, Mars, Jupiter, and Saturn were all visible – until the sky started to grow light. Then we enjoyed driving through McDonald’s for what my father-in-law would call a “naughty breakfast” (not on the diet!).
The comet should now be visible in the night sky, and we’re going out to take another look!
If you want to try to find it, too, you can find a sky map here. Happy hunting!
Camera Geek Info (comet and horizon)
- Canon EOS 60D in manual mode set at f/4, 1 second exposure, ISO 640
- Canon EF 70-300mm f/4-5.6L IS USM lens, set at 100 mm, manual focus
- Cable release
- Tripod
Camera Geek Info (comet and clouds)
- Canon EOS 60D in manual mode set at f/4, 1 second exposure, ISO 1000
- Canon EF 70-300mm f/4-5.6L IS USM lens, set at 70 mm, manual focus
- Cable release
- Tripod
Camera Geek Info (close up)
- Canon EOS 60D in manual mode set at f/5.6, 1 second exposure, ISO 3200
- Canon EF 70-300mm f/4-5.6L IS USM lens, set at 300 mm, manual focus
- Cable release
- Tripod
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