December 3, 2024

Archives for November 2021

NGC 7789 – Open Cluster in Cassiopeia

NGC 7789 – Open Cluster in Cassiopeia

Telescope: LXD75 SC8 @ f/6.3, LX65 mount, altaz mode

Camera: Baader modified Canon 600Da, interval timer

Filter: GSO IR Blocking Filter

Guide scope: None

Exposure: 38x10sec, ISO 1600, 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, moonlight

Lensed Sky Quality Meter: 18.6

Stacking: Mean with a 1-sigma clip.

White Balance: Nebulosity Automatic

Software: Deep Sky Stacker, Nebulosity, Photoshop

NGC7789 is a large and wonderfully rich open cluster located just west of Cassiopeia. It was discovered by Caroline Herschel in 1782 and is sometimes called Caroline’s Rose. It is a delicate object in small to moderate scopes, but blossoms into a rich field in large telescopes. When viewing this cluster I like to spend some time with the field. At first all I will see are the foreground stars and perhaps a soft glow in the background. As my eye adjusts, the first faint stars appear, and then it slowly blooms into a beautiful patch of stardust.

This is one of a series of images that I have been taking to explore using relatively simple equipment and techniques. This is the second time that I imaged this cluster using this system. The sky conditions were much better on this evening so I decided to give it another shot and I’m very happy with the results. Not bad for 10 second exposures with an altaz mount.

Caroline’s Rose is currently well placed in the northeast at sunset.

M30 – Globular Cluster in Capricornus

M30 – Globular Cluster in Capricornus

M30 – Globular Cluster in Capricornus

Telescope: LXD75 SC8 @ f/6.3, LX65 mount, altaz mode

Camera: Baader modified Canon 600Da, interval timer

Filter: GSO IR Blocking Filter

Guide scope: None

Exposure: 31x10sec, ISO 1600, 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, moonlight

Lensed Sky Quality Meter: 18.4

Stacking: Mean with a 1-sigma clip.

White Balance: Nebulosity Automatic

Software: Deep Sky Stacker, Nebulosity, Photoshop

M30 is a relatively small, bright, condensed globular that makes a fine target for small telescopes. In larger scopes it resolves nicely into a tiny patch of stardust.

This is one of a series of images that I have been taking to explore using relatively simple equipment and techniques. This is a good example of a patrol image; a quick’n simple image taken just to see what a target looks like. Looking at mjy notes this is only the 3rd time that I have imaged M30, so for me it lies a bit off of the beaten path. I have since visited it several time with my visual gear and it makes a fine target while star-hopping across Capricornus.

M30 is currently well placed to the lower left of Jupiter in the evening sky.

Comet 67P/Churyumov-Gerasimenko

Comet 67P/Churyumov-Gerasimenko 11/6/2021 4h15m EST

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

Camera: Baader modified Nikon 610

Filter: 2” Orion Imaging Skyglow Filter

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

Exposure: 34x60sec, ISO 400, saved as RAW

Darks: Internal (Long Exposure Noise Reduction On)

Flats: 32×1/250sec, 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

This image shows the motion of Comet 67P/Churyumov-Gerasimenko between 4:15am and 5:15am EST on the morning of 11/6/2021 as is swept past upsilon Gemini to the upper right in this field. The comet was glowing at about magnitude 9.9 at a distance of 39 million miles. Comet 67p is the resting site of the ESA Rosetta probe and Philae lander.

Comet 67P/Churyumov-Gerasimenko is currently crossing Gemini in the morning sky.

NGC 188 – Open Cluster in Cepheus

NGC 188 – Open Cluster in Cepheus

Telescope: LXD75 SC8 @ f/6.3, LX65 mount, altaz mode

Camera: Baader modified Canon 600Da, interval timer

Filter: GSO IR Blocking Filter

Guide scope: None

Exposure: 38x10sec, ISO 1600, 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, moonlight

Lensed Sky Quality Meter: 18.4

Stacking: Mean with a 1-sigma clip.

White Balance: Nebulosity Automatic

Software: Deep Sky Stacker, Nebulosity, Photoshop

Located less than 5 degrees from the north celestial pole NGC 188 is one of the most northern objects in the New General Catalog. It is also one of the oldest open clusters known with an estimated age on the order of 5 billion years. Open clusters usually slowly disperse as they interact with other stars in the surrounding galaxy. NGC 188, however, lies above the galactic plane where it is fairly isolated. Composed almost entirely of 12 and 13th magnitude yellow giants, I find this cluster to be quite delicate, requiring very good transparency to be visible in an 8” telescope. Under these conditions it blossoms into a rich field of tiny pinpoints of light on the edge of visibility and it is quite beautiful. In a larger telescope it becomes easier to see, but remains quite faint and subtle.

This is one of a series of images that I have been taking to explore using relatively simple equipment and techniques. This is a good example of a target located in a region of the sky where an altaz mount will show a significant amount of field rotation and tracking can get a bit tricky, but this system still performed quite well.

NGC 188 is currently well placed to the upper right of Polaris in the evening sky.

M20 – The Trifid Nebula in Sagittarius

M20 – The Trifid Nebula in Sagittarius

Telescope: LXD75 SC8 @ f/6.3, LX65 mount, altaz mode

Camera: Baader modified Canon 600Da, interval timer

Filter: GSO IR Blocking Filter

Guide scope: None

Exposure: 36x10sec, ISO 1600, 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, moonlight

Lensed Sky Quality Meter: 18.3

Stacking: Mean with a 1-sigma clip.

White Balance: Nebulosity Automatic

Software: Deep Sky Stacker, Nebulosity, Photoshop

M20, the Trifid Nebula in Sagittarius is one of a series of nebula that grace the summer Milky Way. The red is a tenuous cloud of interstellar hydrogen set aglow by stars embedded in it, the blue is dust in the background reflecting starlight, and the dark lanes are vast streamers of dust in the foreground. Being near the Milky Way this field is crowded with faint stars, though the density of stars is uneven. The dark regions show areas of dust blocking the light from the faint distant stars in the background while the brighter regions are relatively clear avenues into the deep galaxy beyond.

This is one of a series of images that I have been taking to explore using relatively simple equipment and techniques. M20 is one of several examples of nebula that are utterly invisible from my backyard, even in my 16.5”, but are within easy reach of modest imaging equipment. For me, imaging is primarily an extension of visual observing and while the product is a photograph, the thrill is observing targets that are otherwise invisible.

M20 is currently low in the southwest at sunset.