Cave Nebula in Cassiopeia

I came across this in the 'romp' and even though the conditions were poor decided to have a go at a stacked colour image. This is based on 22 mins in L,R,G and B, 114 s exposures. I will revisit to get better data when nautical night returns.

Summer Romp in Nautical Twilight

A warm summers night, nicer outside than insdie a hot house. No nautical night, so I thought I would just browse the heavens, keeping  a single frame as a souvenir of my tour. The colour image is based on single frames of L, R, G, B.  Usual exposure length around 3 mins.

Brocchi's Cluster (part of )

Cave Nebula in Cygnus

Dumbbell Nebula

IC 1848 and IC1871

M8 Lagoon Nebula

M11 Wild Duck Cluster

M16 Eagle Nebula

M17 Omega Nebula

M18

M0 Trifid Nebula

M22

M56

M71

M57 Ring Nebula

Part of the Veil Nebula

Pelican Nebula in Cygnus

This is based on 114s subs, around 60 mins in L,R, G and B. First time I have used the ZWO camera with the Skywatcher refractor.

Wikipedia:The Pelican Nebula (also known as IC 5070 and IC 5067[1]) is an H II region associated with the North America Nebula in the constellation Cygnus. The gaseous contortions of this emission nebula bear a resemblance to a pelican, giving rise to its name. The Pelican Nebula is located nearby first magnitude star Deneb, and is divided from its more prominent neighbour, the North America Nebula, by a molecular cloud filled with dark dust.

The Pelican is much studied because it has a particularly active mix of star formation and evolving gas clouds. The light from young energetic stars is slowly transforming cold gas to hot and causing an ionization front gradually to advance outward. Particularly dense filaments of cold gas are seen to still remain, and among these are found two jets emitted from the Herbig–Haro object 555. Millions of years from now this nebula might no longer be known as the Pelican, as the balance and placement of stars and gas will leave something that appears completely different.

Equipment: Skywatcher ED80 at F/7.5,  Skywatcher EQ6 Pro GEM, ZWO 1600MM Pro, ZWO EFW with ZWO LRGB filters, QHY5IIC guide camera on Skywatcher 9 x 50 finderscope

NGC 6946 Fireworks Galaxy in Cepheus

Subs of 114s, around an hour in each of L,R,G and B. Moon was around 4 days old and not a lot of astronomical night!

Wikipedia:

NGC 6946 (also known as the Fireworks Galaxy or Caldwell 12) is a face-on intermediate spiral galaxy with a small bright nucleus, whose location in the sky straddles the boundary between the northern constellations of Cepheus and Cygnus. Its distance from Earth is about 25.2 million light-years or 7.72 megaparsecs.

Various unusual celestial objects have been observed within NGC 6964. This includes the so-called 'Red Ellipse' along one of the northern arms that looks like a super-bubble or very large supernova remnant, and which may have been formed by an open cluster containing massive stars. There are also two regions of unusual dark lanes of nebulosity, while within the spiral arms several regions appear devoid of stars and gaseous hydrogen, some spanning up to two kiloparsecs across. A third peculiar object, discovered in 1967, is now known as "Hodge's Complex". This was once thought to be a young supergiant cluster, but in 2017 it was conjectured to be an interacting dwarf galaxy superimposed on NGC 6964.

NGC 6888 The Crescent Nebula in Cygnus

The image is based on 114s subs, around 2 hours in each of L, R , G and B. Processed in DSS, PS and Lightroom.

APOD: NGC 6888, also known as the Crescent Nebula, is a cosmic bubble about 25 light-years across, blown by winds from its central, bright, massive star. This sharp telescopic portrait uses narrow band image data that isolates light from hydrogen and oxygen atoms in the wind-blown nebula. The oxygen atoms produce the blue-green hue that seems to enshroud the detailed folds and filaments. Visible within the nebula, NGC 6888's central star is classified as a Wolf-Rayet star (WR 136). The star is shedding its outer envelope in a strong stellar wind, ejecting the equivalent of the Sun's mass every 10,000 years. The nebula's complex structures are likely the result of this strong wind interacting with material ejected in an earlier phase. Burning fuel at a prodigious rate and near the end of its stellar life this star should ultimately go out with a bang in a spectacular supernova explosion. Found in the nebula rich constellation Cygnus, NGC 6888 is about 5,000 light-years away.

Equipment: Celestron 9.25 XLT at F10,  Skywatcher EQ6 Pro GEM, ZWO 1600MM Pro, ZWO EFW with ZWO LRGB filters, QHY5IIC guide camera on Skywatcher 9 x 50 finderscope

The Whale, Ring and Crescent

Losing the  (astronomical) night, so short on exposures. The Whale (NGC 4631) and the Creseent lack data to show decent images. The Ring has a LOT of data, but not enough to show the faint outer ring clearly. So, all work in progress I suppose.

Wikipedia:

The Ring Nebula (also catalogued as Messier 57, M57 or NGC 6720) is a planetary nebula in the northern constellation of Lyra.Such objects are formed when a shell of ionized gas is expelled into the surrounding interstellar medium by a star in the last stages of its evolution before becoming a white dwarf.

The Crescent Nebula (also known as NGC 6888, Caldwell 27, Sharpless 105) is an emission nebula in the constellation Cygnus, about 5000 light-years away from Earth. It was discovered by William Herschel in 1792. It is formed by the fast stellar wind from the Wolf-Rayet star WR 136 (HD 192163) colliding with and energizing the slower moving wind ejected by the star when it became a red giant around 250,000 to 400,000 years ago. The result of the collision is a shell and two shock waves, one moving outward and one moving inward. The inward moving shock wave heats the stellar wind to X-ray-emitting temperatures.

NGC 4631 (also known as the Whale Galaxy or Caldwell 32) is a barred spiral galaxy in the constellation Canes Venatici. This galaxy's slightly distorted wedge shape gives it the appearance of a herring or a whale, hence its nickname. Because this nearby galaxy is seen edge-on from Earth, professional astronomers observe this galaxy to better understand the gas and stars located outside the plane of the galaxy.

Comet 2017 T2 Panstarrs

This is the result of  12 x 60s subs in each of luminance, red, green and blue light. There was a 10 sec pause between each image to give more time for the comet to move (requirement for the processing technique). According to the method I was following, the total data time should be under an hour because comets are such dynamic objects

I was trying to follow Bernard Hubl's method but in the end had to use Deep Sky Stacker and its 'comets and stars' function. 

For Luminance  I produced an image of the comet only.

For R, G and B I produced an image of the comet plus stars. The channels were combined in PS

I stretched both the L and the RGB images in PS and then combined them. 

 The trouble I found with this is that stretching to show  the faint tail with the limited data meant I also developed the streaks left by the stars. My knowledge of PS is not up to removing  broad faint streaks but leaving the tail.

Anyway, for better or worse:

Comet C/2017 T2 Panstarrs

C/2017 T2 (PANSTARRS)

Magnitude: 8.6

Phase: 36 °

Distance: 1.6765au

Solar distance: 1.6185au

Velocity: 33.1km/s

Estimated tail length: 0.04au