MrJackDog

MrJackDog OP t1_j8apse9 wrote

I photographed this in September 2022 under the dark skies of Highland County, Virginia, using a Sony A7III camera and a 85mm Sony GM lens. The camera I had astro-modified by removing a stock filter so it would be sensitive to red wavelengths present in the nebulae.

The image is a combination of three separate images: two exposures of the land at different focal lengths and one image of the sky, itself a stack of 60 separate 60 second images. For the sky images, the camera and lens sat on a star tracker, a portable mount that counters the earth’s rotation allowing for long exposures without star trails.

I shot an hour worth of 60 exposures with this set-up. After collecting all these exposures, I used a free program called Starry Sky Stacker to “stack” the images — compiling the data in the exposures together to refine the target and reduce noise.

After I shot the sky, I then shot the land using the same camera and lens from the same vantage point. I shot two 4 minute exposures for a focal blend of the foreground and background. Once I had all these images, I used masks in photoshop to blend all the images together for the final composite.

Astrophotography is a hobby with many variations and many purists. Some frown on these composite images - I shoot and enjoy many different types of astrophotography and no matter what the technique, my goal is the same: to share the same sense of awe that I feel when out under a clear dark sky taking in the cosmos.

For more of my work, check out my Instagram: @brennangilmorephoto

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MrJackDog OP t1_j6efhi3 wrote

The recently appeared comet, C/2022 E3 (ZTF) reaches its closest point to Earth on February 1 and has become an evening object in the northern sky. It is not quite visible to the naked eye, but can easily be spotted with binoculars and long-exposure photography.

Photographed on January 24, when the comet c/2022 e3 ZTF had sprouted a large “antitail.”

This is a composite image over separate sky and land exposures: sky - 5x90s exposures, land: 300s - exposure.

Camera/lens: Sony A7iii + Askar FMA180

For more comet photos (and astrophotography in general), check out my Instagram.

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MrJackDog OP t1_j2fhi76 wrote

Descriptions of each photo (from left to right, top to bottom):

Row 1:

  • Comet C/2022 E3 (ZTF)
  • The Angel Nebula
  • Geminid meteor shower
  • Dark Shark Nebula
  • Orion rising
  • Elephant Trunk Nebula

Row 2:

  • M33 Triangulum Galaxy
  • Orion over Goshen Pass, Virginia
  • Milky Way core over Goshen
  • The Northern Trifid Nebula
  • Comet A1 Leonard and M3 star cluster
  • Jupiter and the Galilean Moons rising
  • The Seagull Nebula

Row 3:

  • Mars conjuction with the Moon
  • Jellyfish Nebula
  • Pleiades star cluster
  • Milky Way over Old Cabell Hall, UVA
  • Cygnus region
  • Milky Way core over Lake Michigan

Row 4:

  • Star trails
  • Planets: Mars, Jupiter, Saturn, Neptune, Uranus
  • Milky Way, Highland County, Virginia
  • Milky Way, Highland County, Virginia
  • Sun
  • Antares rocket launch, Wallops Island
  • Whirlpool Galaxy
  • NGC 1330

Row 5:

  • Full Buck Moon, Smith Mountain Lake
  • Crescent Moon over Chihuahua, Mexico
  • Heart Nebula, Highland County
  • Orion over snowy field
  • Orion’s Belt
  • Milky Way over Prada Marfa, Texas

Row 6:

  • Rho Ophiuchi and Blue Horsehead Nebulae
  • Milky Way panorama over Hays Creek
  • Sunflower Galaxy
  • Milky Way panorama over the Maury River
  • Rho Ophiuci
  • Tau Hercules Fireball Meteor

Row 7:

  • Spaghetti Nebula
  • Lunar eclipse
  • California Nebula
  • Squid Nebula,
  • Planetary alignment over Louisa County

The deep sky photos were shot either with an Esprit100mm or Celestron EdgeHD 9.25” telescope and ZWO astro-cameras. The widefield and landscape images were shot with Sony cameras and lenses or a TPO 180mm astrograph.

To follow my astrophotography, check out my Instagram: @brennangilmorephoto

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MrJackDog OP t1_iy3p27r wrote

This is shot at 35 mm so a pretty accurate representation of the size of the constellation in the sky. The moon is around 1/2 of a degree whereas Orion from Rigel at the “foot” of the constellation to Betelgeuse at its “shoulder” is over 20 degrees. So about 40x the size of the moon.

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MrJackDog OP t1_iy0q74m wrote

For this image I used a Sony A7III camera and a Sony 35mm f/1.4 lens. The camera I had astro-modified by removing a stock filter so it would be sensitive to red wavelengths present in the nebulae.

The image is a combination of three separate images: one two-minute exposure of the land, plus two images of the sky: one full spectrum and one only capturing light in the wavelength of the hydrogen alpha. For the sky images, the camera and lens sat on a star tracker, a portable mount that counters the earth’s rotation allowing for long exposures without star trails.

I shot an hour worth of 60s exposures with this set-up. I then added a filter which only allowed light in from the very specific wavelength of light in nebulae and stars (H-alpha) and shot another hour of 60s exposures with this filter. This allowed me to bring out in great detail areas of emissions in the Milky Way that would have been much fainter without this filter. After collecting all these exposures, I used a free program called Starry Sky Stacker to “stack” the images — compiling the data in the exposures together to refine the target and reduce noise.

Once I had done that with both the H-alpha exposures and the full spectrum exposures, I was able to compile the final sky image. To do this I split the full spectrum image into its individual RGB components and replaced the Red channel with the H-alpha image. With that the sky image was near final, and I only needed to make some global adjustments in Adobe Lightroom to get it to the style I wanted.

After I shot the sky, I then shot the land. Once I had all these images, I used masks in photoshop to blend all the images together for the final composite.

For more of my work, check out my Instagram: @brennangilmorephoto

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