Hello, welcome to a blog for people new to astronomy/astrophotography, written by me, a beginner too. With 'how-to's', equipment guides, processing tips and more, I aim to encourage and support us all on our individual and collective learning journeys in this exciting hobby. Whether a beginner or an intermediate, do come join in. Find out how and more about me, this blog and my own learning journey, at https://undersouthwestskies.blogspot.com/2025/01/welcome-to-my-new-astronomyastrophotogr.html
A retired Welshman living in wonderful Plymouth in SW England, I’m a family man, novice sailor and boat builder, astrophotographer and motorhomer. With a passion for all things to do with education and the sea and skies above, I have a sense of adventure and innate curiosity. I write three blogs. ‘Arwen’s Meanderings’ charts my learning to sail a self-built John Welsford designed ‘Navigator’ yawl. Look out for her accompanying YouTube channel www.YouTube.com/c/plymouthwelshboy . ‘UnderSouthWestSkies’ follows my learning journey as I take up astronomy and astrophotography; a blog for beginner’s new to these hobbies, just like me. ‘Wherenexthun’, a co-written blog with my wife Maggie, shares how we ‘newbies’ get to grips with owning ‘Bryony’ an ‘Autosleeper’s Broadway EB’ motorhome, and explores our adventures traveling the UK and other parts of Europe. Come participate in one or more of our blogs. Drop us a comment, pass on a tip, share a photo. I look forward to meeting you. Take care now and have fun. Steve (and Maggie)
A new astronomy location for me. Up at Yelverton on the old RAF Harrowbeer airfield right next to Knighthayes tea shop. I tucked into one of the old aircraft standing bays.
The target for the night was NGC 869, and NGC 884, a double star cluster. My first ever imaging of a double star cluster. Not ideal conditions; a full moon all night and wraith like fog banks just at ground level. No wind and temperatures dropping to around 3C. Some humidity requiring the use of dew bands.
Throw in wandering sheep, a few boy racers doing the circuit and some 'dodgy looking punters in cars and vans driving around slowly at midnight and it was a more 'edgy', 'uncomfortable' experience compared to my normal experiences down Wembury beach car park and at Wembury Point.
Equipment for the night was
Canon 800D
Zenithstar 61ii with field flattener
RVO 32mm F/4 guide scope with ZWO 120mm mini guide cam
ASIair mini
Skywatcher star adventurer 2i with William Optics wedge base
Skywatcher stainless steel tripod
Skywatcher 12v 7 amp power bank
Various power packs, dew straps and bits a pieces like intervalometer
One new piece of equipment is proving very useful. The 'move-shoot-move' green laser pen which can be attached to the polar-scope eye viewing piece on the SWSA. It makes setting up the tracker in line with Polaris so much quicker. Polar alignment on the ASiair is consequently quicker as well.
So, data collection? I managed to get
180 x 60" lights at ISO 800 (three hours worth)
15 each of darks, biases and flats
For the first time since buying the ASIair mini, I have managed to get to grips with it and the screen shots below show my first night of proper successful guiding.
There is no declination on the SWSA2i tracker. Getting an average RA of 0.72 - 0.86 is pleasing - guiding was pretty spot on
The time lapse below gives a flavour of the night time conditions. Over the next few days I will process the data in SIRIL, GraXpert and Affinity Photo and publish the result here as a postscript.
The full moon proved to be very, very bright on this night and humidity was an issue as plunging temperatures and warmed land led to low level wraith like fog patches appearing and disappearing regularly through the night.
And an apology. In the video I labelled it NGC 469 by mistake - sorry! It is of course NGC 869/884 or Caldwell 14
Postscript:
The final image of NGC 869/884
Post editing details:
Stacked and cropped in SIRIL
Background extraction in GraXpert
Deconvolution, photometric colour calibration, green noise removal in SIRIL
Starnett ++ removal in SIRIL
Denoising of starmask image in GraXpert
GHS and saturation stretches in SIRIL
Final edits in RAW camera in Affinity Photo
NGC 869/884 is a double cluster of stars approximately 7460 light years away from earth. 12.8 million years old (so relatively young) and also known as Caldwell 14, the clusters lie in the constellations of Perseus and Cassiopeia. Visible to the naked eye from dark sky sights when there is no moon, the clusters have a magnitude of 5.3 to 6.1 and each cluster contains 300 to 400 young hot stars.
The clusters were first 'discovered' and described by the Greek astronomer Hipparchus in 130 BCE
Each cluster has around 300+ blue white super giant stars which are moving through space towards Earth at around 80,000 kph. There are also some brighter orange stars within each cluster as well. In mythology, the double cluster represents the jewelled handle of the sword presented to Perseus by the Gods, along with his helmet and shield.
Space co-ordinates for the double cluster? RA 2hr. 20m Dec +57deg. 08m
Finally, the double clusters each have a mass >20,000 solar masses.
