Imaging session - My first effort on the NGC 6888 The Crescent Nebula

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 I am slowly getting to grips with the idiosyncrasies' of the EQM-35-Pro.  Balancing in DEC is straightforward as it moves and rotates easily. Balancing in RA is tricky.  The grease used by Skywatcher is gunky and makes rotation stiff. 

Anyway, here are the acquisition details of my latest effort - NGC 6888 The Crescent Nebula.

equipment: 

Canon 800 D DSLR astro-modded

WO Zenithstar 61ii refractor with field flattener

ASIair mini with ZWO 120mm mini guide cam and RVO 32mm guide scope

Celestron Lithium Pro power bank

EQM-35-Pro

photograph details: 

lights: 60 x 180" at ISO 800

20 each of flats, biases and dark frames

And here are the photos, after post editing in SIRIL, GraXpert and Affinity Photo: 

I never understand how I manage to get a different result on exactly the same data every time I use SIRIL. Baffling! 

and here are two further processed from the originals. If you asked me what I did - I have no idea! 

So, NGC 6888 - around 5000 light years away and discovered by Herschel in the late 1700's.  An emission nebula in the constellation Cygnus, it is formed by fast stellar winds from the Wolf-Rayet star WR 136. 

This stellar wind collides with and energises a slower moving wind ejected by the star when it became a red giant some 400,000 years ago.  The result of this collision is a shell and two shock waves. 

Postscript:

I have done some follow up post editing and here is my final image from this data set:

Discussion - Why does the universe exist?

 It has kept me thinking once or twice on some night outings 😆 

BBC News - Scientists in a race to discover why our Universe exists https://www.bbc.com/news/articles/cjwvgevjjl6o

Discussion - Expectations versus reality in Astrophotography

Blogger isn't always the most intuitive platform to navigate - but it is free and simple to use and manage. 

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 I recently read a very interesting short piece about this. Unfortunately, I can't remember where I saw the piece. But I can remember some of the basics and I thought it was very apt for beginners, new to astronomy and astrophotography in particular. 

When I first started my astrophotography journey, I was very smitten with the images I was seeing in magazines and on-line, particularly of galaxies, nebulae and milky way landscapes. Naively, I thought after some photography basic courses, I'd be able to go out and capture such images. But, of course, I now know differently. 

Expectations vs reality!

It isn't just about knowing how to get your DSLR off auto is it? It's all those astrophotography programs - Sequator, SIRIL, Deepskystacker, PixInSight, GraXpert. The list is endless. Each requires significant investment in time - practice, practice, practice. How to stack frames! How to take calibration frames. Tracking the stars! Getting my head around long exposures and the whole host of post editing techniques to capture colour, shape, texture of night sky objects, was such a steep learning curve. How disappointed was I as my first efforts materialised on the rear view screen? Dim, noisy, small and frankly dull. Where was the colour, shape, texture? It took some time to grapple with the histogram and process of stacking multiple images.  

Expectations vs reality! Learning how to use the various programs - so much time on YouTube! 

And what about setting up equipment on the night? How many hours have I spent trying to polar align accurately? Trying to work out the intricacies of ASIair settings? Cable management so that they didn't dangle and snag. Tripping over the tripod; wasting how many frames because of dew on the lens or forgetting to replace batteries in a tracker. So many hard learned lessons and the need for checklists! 

Expectations versus reality! Tough learning moments. 

Nothing prepares you for the amount of time spent researching equipment needs. My first telescope was, on reflection, a bad purchase. The telescope was good but just not appropriate for what I as trying to achieve. Telescopes, camera lenses, filters, dew bands, guide scopes, ASIair mini, guide cams and scopes, power tank supplies, tripod types, trackers. What a minefield! After my first poor purchase, I took it slowly and used forums like stargazing lounge and cloudy nights to seek advice. Astrobin helped me visualise what each telescope and lens could achieve in tandem with a canon dslr. I came to realise that the most important bit was the mount! From Ioptron skytracker, to Skywatcher Star Adventurer 2i pro; and now to an EQM-35-Pro. Payload, tracking accuracy, polar alignment, stability, weight, reliability, ease of maintenance - all have to be considered. 

Expectation vs reality. Doing our research, consulting and seeking advice. It takes so much time. 

Processing. I just didn't understand how much time would be spent on post editing an image. I genuinely thought I'd capture a finished image almost immediately. Foolish boy! Reviewing images to get rid of the poor ones; stacking the remaining ones to get one master image with improved noise to signal ratio. Curves, levels, histogram stretching! A dark art! Noise reduction, colour calibration, deconvolution. So many processes, so many different ways of doing your workflow!  It has taken me time to get my own personal workflow and even now I'm not sure it's right. 

Expectation vs reality. You can edit the exact same data several times and each time get a different visual result. And, you may be like me - none the wiser as to whether its an accurate reflection of what exists in reality. Astrobin becomes your friend! 

I wasn't prepared for the range of emotions I would feel and develop as an astrophotographer. It really is awe and wonder stuff. I was so excited when my first galaxy appeared on the rear view screen; an indistinct fuzzy blob, but a galaxy nonetheless! Light years, the time taken for a photon of light to reach your camera sensor. Time travel - when it left 250,000 light years ago! The image you see on the viewfinder.....one from the past. Is it still there now? How might it have changed? So many questions! The gradual understanding of seasonal skies, lunar phases, planetary alignments; the arrival and departure of distant comets. Excitement, curiosity, frustration, peace, calm, tranquility.

And patience. so much patience! the number of nights I have arrived expecting clear skies to find cloud. equipment failures - when the ASIair wont connect to the camera. When polar alignment just keeps failing for some reason I cannot work out. Two steps forward, five backwards; so often! 

Resilience, patience, consistency, attention to detail, methodicality, organisation, curiosity, determination. Kindness to one's self. 

Expectations vs reality. You are going to learn about your character and develop some emotional skills! 

It is Ok to get a so-so image. All images are hard won successes. Be kind to yourself. learn to walk before you can run and all that! Ignore those perfect social media images. Something to work towards over the long term. Your first photo of the moon; the first comet; that first milky way landscape. It doesn't matter about their quality. Just cherish them. They were milestones on your astrophotography journey; not meant to impress others, but definitely a culmination of your hard won fledgling skills. Personal growth and development! Behind every image you take there will have been new skills learned, patience, planning, troubleshooting, problem solving. We are learning to deal with setbacks, even anticipating them. 

Expectations vs reality. Astrophotography is a slow, complex, challenging and rewarding learning journey. You have to be a willing life-long learner to embark on it. 

Don't forget that you need a supportive community around you if you want to make progress. Online forums, Facebook groups, Astrobin community. Seek feedback and advice. You won't always like it but embrace it. Seek out those who inspire you; who understand what it is like to be a beginner; who value you for starting on the journey they may be further along. Dont be afraid to ask questions - there is genuinely nothing like a dumb question - remember you don't know what you don't know! 

Expectations vs reality. Embrace your social side! 

Curves

Discussion - Walking on the moon

 BBC News - Will Rosemary Coogan be the first Briton to walk on the Moon? - BBC News https://www.bbc.co.uk/news/articles/czxyv3z710do

What is happening in the night sky during May 2025?

 What’s happening in May?

This is the first time I have done a summary of the monthly night sky and I have drawn from various magazines and websites for this short summary. I am going to try and do this every month from now on, as it helps me plan out what I am aiming to observe. I have done it from a mainly UK perspective. 

DATE:	ASTRONOMICAL EVENT
	THROUGHOUT THE MONTH:
	Venus: Appears very bright and low in the east in the hour before sunrise all month; shines at magnitude –4.7 and located south of the Great Square of Pegasus, among the stars of western Pisces. Venus extends its elongation from the Sun during the month and is carried eastward against the background stars of Pisces, away from Saturn. A waning crescent Moon stands within 7° of Venus on the 23rd. Venus is best observed in twilight to avoid the dazzling brilliance of the planet when viewed in darkness. Mars: Easy to find in the west in the first few hours of the night, all month long. Sets around midnight to 1 a.m. local time. Mars will be near the Beehive Cluster (M44) in early May. Two days later, on the 3rd, a waxing crescent Moon joins Mars. Our satellite passes within 2° of the planet, which is now skirting the outer limits of M44. The next evening, Mars is 40′ due north of the centre of the Beehive, a stunning pairing in binoculars or low-power telescope eyepiece. During the rest of May, Mars continues across eastern Cancer and moves into Leo on the 25th. By the 31st, Mars stands 9° northwest of Regulus, Leo’s brightest star. It remains visible until roughly 1 a.m. local daylight time. It takes Mars nearly two years to revisit the same area of sky, and this May we have the opportunity to see it return to the Beehive Cluster in Cancer. They’ll both appear within the same 10x50 binocular view from around April 21st onwards, but if you return to the pair over consecutive nights, you’ll see the gap between them rapidly close. Jupiter: Shines brightly in the west following sunset all month. Early in the month it sets about two hours after the Sun, but by late May it's setting only an hour after sunset. Last chance to grab a good view before it drops out of sight for midsummer - the narrowing observing window will provide some interesting events involving the Galilean moons as recompense. Saturn: Begins the month next to Venus, low in the eastern sky before sunrise. Saturn stands 4° south of Venus on May 1. Both planets are above the horizon by 5 a.m. local daylight time. Saturn shines at magnitude 1.2 and its rings are close to edge-on. Viewing Saturn’s rings is difficult with the low altitude and approaching twilight, but it’s worth a try in the first few days - glimpsing the backlit side of the rings. If seeing conditions allow, might see the gossamer-thin black line of the rings’ shadow on Saturn’s 16″-wide disk. After May 6 — the date of Saturn’s equinox, when the Sun is exactly edge-on to the rings — the shadow essentially disappears. On May 7, the southern face of the rings, tilted by 2° to our line of sight, becomes sunlit for the first time in more than 15 years. Observing these fascinating changes in the rings is challenging, but it’s worth the effort if you have a large telescope and clear eastern horizon. Saturn continues to climb higher in the morning sky and meets with a waning crescent Moon on May 22. By May 31, it’s rising before 3 a.m. local daylight time and stands 15° high in the eastern sky at the onset of morning twilight. Neptune: also lies in this direction, far beyond both Venus and Saturn, and is difficult to see in early May, when both Venus and Saturn lie about 3° from the more distant world. By the end of May, Neptune stands 1.6° northeast of Saturn and can be spotted with a pair of binoculars, glowing at magnitude 7.8. Mercury: appears very low in the eastern morning sky in early May, shining at magnitude 0.1. It rises 50 minutes before the Sun on May 1, and only 40 minutes ahead of the Sun by May 12, when the planet has brightened to magnitude –0.5. Its southerly declination makes it a tougher target for Northern Hemisphere observers, whereas those in the Southern Hemisphere have a great view. Spot a gibbous disk growing from 60 percent lit on the 1st to 77 percent lit on the 12th. Mercury quickly dips out of view after the second week of May and reaches superior conjunction with the Sun on May 29. Like its inner Solar System neighbour Venus, Mercury is also currently a morning planet, but positioned too low to really be seen properly from the UK in the dawn twilight. Uranus: is out of view and is in conjunction with the Sun May 17. Moon: Throughout May, the Moon will be near Mars and Venus. On May 23rd, the Moon will pass close to both Venus and Saturn, offering a chance to see the three objects together in the morning sky.
2nd	Asteroid Opposition (May 2): Asteroid Vesta will reach opposition on May 2nd, providing an opportunity to spot it with binoculars; will be at its brightest for the year. Can be seen through binoculars under ideal dark sky conditions. It will lie in northern Libra in early May and enters Virgo on May 6th and tracks through Virgo’s far mid-west regions for remainder of month.
5th	Eta Aquariid Meteor Shower (May 5): The Eta Aquariids meteor shower, active throughout April and May, reaches its peak on May 6th, potentially offering up to 50 meteors per hour. The shower is active from April 19 to May 28, and peaks the evening of May 5. The radiant lies near Zeta (ζ)  Aquarii. Need to be early riser or late night owl to see a few meteors.
12th	Full "Flower" Moon (May 12): The full Moon, also known as the Flower Moon, will occur on May 12th. This year, it will also be a micro-moon, meaning it will be slightly farther from Earth than usual.

 Reference sources: 

BBC Sky at Night Magazine May 2025

Astronomy Now magazine May 2025

High Point Scientific Website