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Telescope: Astro-Tech 8” f/8 Ritchey-Chretien, Orion Atlas EQ-G

Camera: Canon EOS Ra, Baader Mk III MPCC

Filter: Orion Imaging Skyglow Filter

Guide scope: Astro-Tech 60mm, Starlight Xpress Super Star, PHD2

Exposure: 43x60sec, ISO 800, saved as RAW

Darks: Internal (Long Exposure Noise Reduction On)

Flats: 32×1/25sec, Tee shirt flats taken at dusk

Average Light Pollution: Red zone, Bortle 8, fair transparency, haze

Lensed Sky Quality Meter: 18.4

Stacking: Simple average to accommodate the two different exposure times

White Balance: Nebulosity Automatic

Software: Backyard EOS, Deep Sky Stacker, Nebulosity, Photoshop

M15, a bright, condensed globular cluster in a relatively lonely stretch of sky in Pegasus. It is one of the oldest known globular clusters with an estimated age of 13.2 billion years and the first globular cluster found to have a planetary nebula (Pease 1), one of only four planetary nebula associated with a globular cluster. M15 is also one of the most condensed globular cluster and at some point in the distant past it experienced a core collapse that may have heralded the formation of a black hole in its nucleus. This is supported by the fact the M15 is an x-ray source.

This is the last of three first-light images taken with my new Canon EOS Ra camera. I had originally planned to end the evening with an emission nebula, but the hazy sky conditions didn’t look suitable, so I opted for a bright globular instead.

M15 is currently well placed rising the east in the early evening and is high in the south at dawn.

Telescope: Astro-Tech 8” f/8 Ritchey-Chretien, Orion Atlas EQ-G

Camera: Canon EOS Ra, Baader Mk III MPCC

Filter: Orion Imaging Skyglow Filter

Guide scope: Astro-Tech 60mm, Starlight Xpress Super Star, PHD2

Exposure (6-26-2021): 27x120sec, ISO 800, saved as RAW

Exposure (7-2-2021): 28x180sec, ISO 800, saved as RAW

Darks: Internal (Long Exposure Noise Reduction On)

Flats: 32×1/25sec, Tee shirt flats taken at dusk

Average Light Pollution: Red zone, Bortle 8, fair transparency, haze

Lensed Sky Quality Meter: 18.1 (6-26) & 18.5 (7-2)

Stacking: Simple average to accommodate the two different exposure times

White Balance: Nebulosity Automatic

Software: Backyard EOS, Deep Sky Stacker, Nebulosity, Photoshop

M27, the Dumbbell nebula, is an expanding shell of gas that was ejected from a sun-like star as it exhausted its hydrogen fuel. Swollen into a red giant, the star shed its outer shell while its core collapsed into a white dwarf. Fierce UV radiation from the collapsed core sets the surrounds gas aglow with the blue/green light of doubly ionized oxygen. The diameter of the nebula is about 1 light-year with an estimated age of 9,800 years. Located between Sagitta and Cygnus, M27 is fairly easy to find with a small telescope. Visually, it shows two lobes connected by a neck of nebulosity, giving the nebula its characteristic dumbbell shape.

This is the second of three first-light images taken with my new Canon EOS Ra camera. The source images were taken over two evenings about a week apart: 27x120sec on 6-26 and 28x180sec on 7-2. The exposure times reflect the poor transparency on the evening of 6-26. I wasn’t sure how well the two different exposure times would combine, so I used a simple average algorithm rather than using the usual sigma clip.

M27 is currently well placed rising the northeast in the early evening and is high in the south after midnight.

Telescope: Astro-Tech 8” f/8 Ritchey-Chretien, Orion Atlas EQ-G

Camera: Canon EOS Ra, Baader Mk III MPCC

Filter: Orion Imaging Skyglow Filter

Guide scope: Astro-Tech 60mm, Starlight Xpress Super Star, PHD2

Exposure: (18 + 29)x60sec, ISO 800, saved as RAW

Darks: Internal (Long Exposure Noise Reduction On)

Flats: 32×1/25sec, Tee shirt flats taken at dusk

Average Light Pollution: Red zone, Bortle 8, poor transparency, haze

Lensed Sky Quality Meter: 18.4

Stacking: Mean with a 1-sigma clip.

White Balance: Nebulosity Automatic

Software: Backyard EOS, Deep Sky Stacker, Nebulosity, Photoshop

Globular clusters are relics of the ancient universe and M13 is no exception with an estimated age of 12 billion years. Their great age is an indication of their unusual stability. One consequence of this stability is that any heavy elements that their stars have made remains buried in their cores and the cluster itself has little, if any, interstellar dust. M13 is one of the few globular clusters with a dust-like feature that can be seen as a dark lane extending to the lower left of the core. It is possible that this dust lane is not really associated with M13, but instead is an independent object that just happens to be in front of the cluster.

This is the first-light image taken with my shiny new Canon EOS Ra. The weather really hasn’t cooperated yet, so I combined two sets of source images taken on the evenings of June 26^th and July 2^nd. One thing that I noted is that even though the sensor was very warm (33-47C) all of the source images were very clean with no hot or cold pixels. Being a mirrorless camera the shutter was smooth and quite. This was one feature that I was particularly interested in after having a few problems with the relatively heavy and complex mirror system in my Nikon D610a. I do luvs the Nikon, but I was curious enough about the performance of a modern mirrorless camera to give the EOS Ra a try. I was also fascinated by the idea of using a full-frame DSLR specifically made for astrophotography and I have enjoyed my previous Canon cameras. So far I am really liking the new camera! It was very easy to integrate into my imaging gear and has been very easy to use. Wonderful!

M13 is currently well placed high in the northeast as the sky darkens.

Telescope: ES Comet Hunter MN6 at f/4.8, Orion Atlas EQ-G

Camera: Baader modified Nikon 610

Filter: 2” Radian Triad Ultra Hb, OIII, Ha, SII filter

Guide scope: Williams Optics 50mm, ASI290MM mini, PHD

Exposure: 15x180sec, ISO 400, saved as RAW

Darks: Internal (Long Exposure Noise Reduction On)

Flats: 64×1/5sec, tee shirt flats taken at dusk

Average Light Pollution: Red zone, Bortle 8, poor transparency, moonlight

Lensed Sky Quality Meter: 18.0

Stacking: Mean with a 1-sigma clip.

White Balance: Nebulosity Automatic

Software: Backyard Nikon, Nebulosity, Deep Sky Stacker, Photoshop

NGC 7635 is almost the inverse of a planetary nebula. Planetary nebula are expanding shells of gas shed from a dying star. The Bubble Nebula is formed from the intense radiation a hot blue star pushing out a sphere in the surrounding gas, making an empty bubble and setting the hydrogen aglow with a beautiful red color. This wide field view includes the open clusters M52 (upper left) and NGC 7510 (lower right), and the emission nebula NGC 7538 is to the upper right.

The Bubble Nebula rises in the northeast late in the evening and is high overhead at dawn.

Telescope: ES Comet Hunter MN6 at f/4.8, Orion Atlas EQ-G

Camera: Baader modified Nikon 610

Filter: 2” Radian Triad Ultra Hb, OIII, Ha, SII filter

Guide scope: Williams Optics 50mm, ASI290MM mini, PHD

Exposure: 67x60sec, ISO 400, saved as RAW

Darks: Internal (Long Exposure Noise Reduction On)

Flats: 64×1/5sec, tee shirt flats taken at dusk

Average Light Pollution: Red zone, Bortle 8, poor transparency, moonlight

Lensed Sky Quality Meter: 17.6

Stacking: Mean with a 1-sigma clip.

White Balance: Nebulosity Automatic

Software: Backyard Nikon, Nebulosity, Deep Sky Stacker, Photoshop

M17 is a stellar nursery lying about 6,000 light years away along the southern Milky Way in the Sagittarius-Carina arm of our galaxy. The soft red glow of this beautiful emission nebula comes from young stars embedded within the nebula setting the surrounding interstellar hydrogen aglow. M17 is one of the brightest emission nebula is the sky and is visible in small telescopes under dark skies. Even under urban skies the bright inner region of the nebula is a fairly easy target.

M17 is currently well placed in the evening sky rising in the southeast as the sky darkens.

Telescope: ES Comet Hunter MN6 at f/4.8, Orion Atlas EQ-G

Camera: Baader modified Nikon 610

Filter: 2” Radian Triad Ultra Hb, OIII, Ha, SII filter

Guide scope: Williams Optics 50mm, ASI290MM mini, PHD

Exposure: 36x240sec, ISO 400, saved as RAW

Darks: Internal (Long Exposure Noise Reduction On)

Flats: 64×1/5sec, tee shirt flats taken at dusk

Average Light Pollution: Red zone, Bortle 8, good transparency

Lensed Sky Quality Meter: 18.7

Stacking: Mean with a 1-sigma clip.

White Balance: Nebulosity Automatic

Software: Backyard Nikon, Nebulosity, Deep Sky Stacker, Photoshop

IC 1396 includes an open cluster and a vast region of H-alpha emission. If I re-frame this field a little bit farther to the east I can just about capture the width of the nebula. IC 1396A is the sinuous wave that makes up the southern border of a dark nebula called the Elephant’s Trunk. It is neat to take a close look at some of the fascinating detail scattered across this region. I have also had a lot of fun glimpsing the Elephant’s Trunk with my little Revolution Imager 2 video camera where it appears as a faint wisp against the background stars.

IC 1396 is currently well placed in the northeast late in the evening and is high overhead at dawn.

Telescope: ES Comet Hunter MN6 at f/4.8, Orion Atlas EQ-G

Camera: Baader modified Nikon 610

Filter: 2” Radian Triad Ultra Hb, OIII, Ha, SII filter

Guide scope: Williams Optics 50mm, ASI290MM mini, PHD

Exposure: 19x240sec, ISO 400, saved as RAW

Darks: Internal (Long Exposure Noise Reduction On)

Flats: 64×1/5sec, tee shirt flats taken at dusk

Average Light Pollution: Red zone, Bortle 8, good transparency

Lensed Sky Quality Meter: 18.7

Stacking: Mean with a 1-sigma clip.

White Balance: Nebulosity Automatic

Software: Backyard Nikon, Nebulosity, Deep Sky Stacker, Photoshop

The Crescent Nebula is an emission nebula, usually a cloud of diffuse interstellar hydrogen set aglow by hot young stars born within it. However, in this case the nebula was made by a single, massive, fiercely energetic Wolf-Rayet star at its core. Some 250,000-400,000 years ago this star ejected its outer surface while it was a red giant, forming the expanding shell of the nebula. As the star collapsed it ejected a fast moving solar wind that is pushing against the slower moving gas in the shell forming a shock front giving the nebula its distinctive shape. The Crescent Nebula lies among the rich star fields in Cygnus and almost gets lost in the Milky Way. The five stars forming a “W” across the northern edge of the nebula makes a handy reference for locating this field visually or with a video system.

NGC 6888 is currently well placed in the northeast late in the evening and is high overhead after midnight.

Telescope: ES Comet Hunter MN6 at f/4.8, Orion Atlas EQ-G

Camera: Baader modified Nikon 610

Filter: 2” Radian Triad Ultra Hb, OIII, Ha, SII filter

Guide scope: Williams Optics 50mm, ASI290MM mini, PHD

Exposure: 10x120sec, ISO 400, saved as RAW

Darks: Internal (Long Exposure Noise Reduction On)

Flats: 64×1/5sec, tee shirt flats taken at dusk

Average Light Pollution: Red zone, Bortle 8, poor transparency, clouds

Lensed Sky Quality Meter: 18.4

Stacking: Mean with a 1-sigma clip.

White Balance: Nebulosity Automatic

Software: Backyard Nikon, Nebulosity, Deep Sky Stacker, Photoshop

M16 is actually the cluster in the upper right section of the nebula. The nebula is very subtle and can be difficult to see visually, though it shows well under dark skies. The name, the Eagle Nebula, comes from the dark lanes in the middle which resembles an eagle grasping a fish. These dust lanes are also the famous ‘pillars of creation’ imaged by the Hubble Space Telescope. The nebula is a beautiful expanse of interstellar hydrogen set aglow from young stars embedded within it. M16 lies in the Sagittarius-Carina arm of the Milky Way, the next arm inwards from ours towards the core of our galaxy, so you are looking across the gap between adjacent spiral arms.

M17 is currently well placed in the southeast late in the evening and is high in the south after midnight.