Discussion - Has technology made me lose sight of the awe and wonder of the night sky?

First visit to this astronomy/astrophotography blog? Well, firstly a warm welcome to you and thanks for stopping by. After reading this post, if you want to find out more about me and this blog, why not visit my introductory page at https://undersouthwestskies.blogspot.com/2025/01/welcome-to-my-new-astronomyastrophotogr.html You can also browse other posts by using the search bar or the blog post list on the right hand side and I'd really like to hear from you via the comment boxes. Drop me a tip, an observation or a question. Take care and clear skies to you. Steve

 With blocked horizons to my south and west, an incoming cloud bank from the south west, a limited viewing time slot, a rare clear night for three hours and the light pollution from my neighbour's kitchen light which is left on all night, I was feeling highly pressured the other night! 

I'd spent much of the day, as for most potential night observation sessions, glued to my phone - checking photopills, google maps, clear skies, sky safari plus, astrobin and the met office weather forecast. Where to go? What to see and image? What had others done on Astrobin? Plans, more plans, rewritten plans. Most times I enjoy this process but when there have been very few nights thus far this year where skies have been relatively clear, this first one for weeks - well it was causing me stress. FOMO type stress! 

As it was, the forecasts began to worsen and so I gave up planning a trip somewhere. Another crushing disappointment! But, lo and behold, the skies above my house began to clear around 9pm; a direct defiance of the weather forecast apps. Would it clear? Was there a chance that I could just.........

..... set up and sneak out into the garden for a short three hour astrophotography session based on whatever I could see in the skies above my garden?  Wow.....opportunistic! All that planning about to be chucked out the window! I felt quite 'devilish and rebellious' I must say!  No packing the car, gathering appropriate clothing and packing flask and snacks.  Just everything set up by 10pm waiting for darkness to fall. Stress free - literally moving equipment from study to garden. Simple! Wonderful! 

I think I have become 'captivated by technology'. A slave to it and too geeky by far. And that's saying something as I have always been geeky! In the last year I have set up autoguiding on my basic rig, got to grips with the ASIair app and then more recently become obsessed with getting my donated EQM-35-Pro to work with all my 'gear'. And let's not get started on my obsession with mastering every post editing astrophotography programme there is! 

Has this desire to get it all working and the pressure to make the best of every limited observation opportunity made me lose sight of something more important? Have I lost sight of the joy, awe and wonder at just pausing, stopping and staring at the night sky above me? For no other reason than to just appreciate its sheer beauty and immensity? 

The privilege of being able to just walk out and set up in your back garden at a moments notice should not be underestimated nor under appreciated. By 11.30pm I had started my imaging session of NGC 7000 above me in the NE sky. For two and a half hours after, I just sat on my new bench below my kitchen window and stared at the sky above whilst my 'technology' went about its little workflow plan. 

At first I tried to trace out the constellations above me but I soon gave up. Why? Because I had forgotten them. Now I never was good at remembering them in the first place but actually I couldn't name one. And I am sure a couple of years ago I could. So what has happened?  So obsessed with getting it all working, getting it all framed correctly, getting the guiding so precise...... did I lose sight of the point of being out there in the first place? To learn new things and to appreciate the cosmos above me? 

I have been privileged to have walked under the extraordinary skies of the Serengeti, the Namibian deserts, and the river estuaries of The Gambia. I've wandered the salt flats of Death Valley under the stars; clambered across the red rocks of Capitol Reef National Park and viewed the stars from the high alps and Kilimanjaro. I can remember that intense feeling of complete awe and wonder; of feeling both infinitely small and inconsequential and yet, simultaneously feeling so unique - the only one of ME - in the entire universe. (Unless of course there are actually parallel dimensions, in which case...... )

I gave up tracing constellations and focused on some star hopping instead where I made better progress. Almach to Mirach to Andromeda. Bingo. Deneb to Sadr to Crescent nebula. Result. Down to the Western Veil Nebula.  Getting better! And then, I realised something immense. I was missing the point of being out there. Star hopping was utilitarian. I knew it because it was an ends to a means - finding a DSO to image. 

I breathed in, slowed my breathing, kept staring up at the sky above and relaxed. A zen moment of mind clearance and slowly my mind started to wander. The bump of a snail falling off the ivy onto the decking. The scurrying of tiny feet across the top of the cushion box - Caligula, our resident rat was on nocturnal prowl. The grunting and snuffles of Hermione our hedgehog as it discovered slugs in the pea patch. The hoot of Ollie our woodland tawny owl; the rustling of ivy outside the kitchen door in the gentle warm night breeze. 

Above me twinkling Vega and despite living in a bortle 5 area, the moon hadn't risen and so an hour in my eyes had become accustomed to the dark; the night sky above began to take on the appearance of a black velvet table cloth over which some uncouth diner had spilt some salt - scattered grains bright against the fabric. 

Tranquility descended. No more expectations and pressure to keep checking the histogram. No jumping up to see that the cabling wasn't snagging. No trying to star hop. No feeling the need to 'absolutely learn and master' the constellation positions. Just me looking up from my comfy bench, sat on my comfy cushion, appreciating the awe and majesty of the vast cosmos above me. 

And questions...... of course I had questions...... my brain can't stop asking questions.... it never rests.... 

...... does space actually end?

...... are there really multiple universes?

...... are we really the only ones out here?

...... is there really a theory of everything?

...... NGC 7000 existed 2500 light years ago and I'm imaging it now - but....is it still there? Has it actually dispersed? 

And of course most importantly ..... is transwarp travel actually theoretically possible? And if so, when? 

I really enjoyed not dashing out to the coast or up onto Dartmoor for a change! Garden astrophotography. What a revelation! 

Imaging session - NGC 7000 and IC 5070 using Optolong L-eNhance EOS clip in filter

I have bitten the bullet and gone ahead with the purchase of an EOS Optolong L-enHance clip in filter for my DSLR. This was against advice from people at various astronomy retail outlets and also on various Facebook forums. Essentially, they felt I should wait until I upgraded my image train to a specific astro cam and filter wheel arrangement and then go for the Optolong L-eXtreme or some such other filter. 

But, I can't afford to upgrade my image train at the moment, nor for the foreseeable future and anyway, I like imaging with my DSLR. 😕

Recently, finding a cloudless night has been about as rare as finding golden hen's teeth. But one did occur a few nights ago and so I went out into the back garden for an imaging session. 

Now I was facing some constraints!

• a 60% waning moon rising at 1 am
• my first try at using a clip in filter with my newly astro-modded DSLR
• a limited sky view - I can only image from NW to NE skies from my garden; or directly overhead towards the zenith. The steep hilly garden to the south with its tall woodland trees block southern sky views. 

I decided to try for an emission nebula - NGC 7000, The North American Nebula. I've given details further down the post. A bonus would be capturing IC 5070, The Pelican Nebula. 

Wanting a widefield view and after my disaster missing Rho Ophiuchi last session (because I used my Zenithstar 61ii), I opted for my samyang 135mm lens. So, equipment on the night was as follows: 

• Samyang 135 mm lens
• Canon 800D astro-modded DSLR
• Optolong L-eNhance clip in filter 
• Skywatcher EQM-35-Pro mount
• ASIair mini
• RVO 32mm F/4 guide scope with ZWO 120mm mini camera
• Red dot finder scope 
• Celestron Lithium Pro battery pack 
• Two dew heater straps
• Two power banks 
• Skywatcher right angled Polar viewer and MSM green pen laser 

So here is the night's images - the same image - wide view and cropped in. Shooting details shown between the images. Remember that Blogger has a 100mb upload capacity and so I have had to reduce the quality of the images somewhat to get them to load up to this post. 

Shooting details: ISO 1600, F/2.8, 300" x 25 with 10 of each calibration frame

Post editing details: Stacked in Siril; background extraction and denoise in GraXpert; colour calibration, deconvolution in Siril; finishing stretches, sharpening and colour balancing etc in Affinity Photo

So, two questions - how did the night set up go; and, how did the post editing workflow progress? 

The night went smoothly. Actually one of the smoothest night set-ups I have had.  From getting out the tripod to finally shooting on the target took just 40 minutes; not my normal 60 or so! Result! 

I was worried that using the clip in filter would cause me some focusing issues but I whacked ISO to 12,600 and then found the brightest star I could find in the sky. Using Live View and my zoom in buttons, I was able to see the star clearly and get sharp focusing straight away. I used a strip of masking tape to then secure the focus position on the lens. 

Because I couldn't see Polaris (due to scaffolding up the side of the house - recent huge flat roof leak - long story - let's not go there 😱) I had to rely on 'All sky align' mode on the ASIair mini. It worked perfectly! Five minute long exposures are the longest I have ever done and BIG result? Guiding was spot on perfect, most of the night it was below 1.0. Seriously, on a stiff to balance EQM-35-Pro - amazing! 

Time spent a few weeks ago working on my imaging train also paid off. I have sorted my cabling and arranged it so that surplus cables are bundled neatly and stored on the imaging rig - reducing the cable rig weight. My son-in-law kindly 3D printed off some tripod powerbank holder clips which helped as well. I will do another post about this at a later date. 

Upshot? I managed to image for around 2 and 1/4 hrs before clouds started to close in. Ideally I would like to try and get three hours worth of images. Maybe I will try and add more images on the clear night - although I am also being tugged by the desire to go off and get some milky way landscape images! 

I am, in all truthfulness, always pleasantly surprised when I manage to get the ASIair working as it should. Initially, things didn't look very promising but then things settled down. 

Ok, what about post editing then?

I am still using Siril version 1.2.6.  I know there is a new, really whoopy new version out but I haven't bothered to download it yet because I am still trying to understand the basics on this simpler version. Small steps and learning to walk before you run and all that! 

However, I am really pleased with these images. The full resolution ones show marked improvements in my post editing skills? So why the sudden leap forward? Well, I have managed to better understand GHS stretches in Siril. I have altered my workflow slightly to do more stretching in affinity photo as well. I better understand how to reduce star intensity and luminosity using JR Ritson Macros for affinity photo (thanks James). For the first time, one of my DSO photos has some 3D depth and structure to it. 

At long last! 

I know there are still many issues not addressed - especially colour saturation and blowing out some of the detail in core areas - but small steps as I said before. I am a 'slow' learner. Persistent, curious, determined, resilient - but 'slow'! 😁😂

So, what about the filter? 

A game changer in my view. Wow. Noticeable effect immediately from my bortle 5 back garden. I won't bother doing a review of the filter as there are many already on the net - try these if you are interested: 

https://astrobackyard.com/optolong-l-enhance-filter/

What are my initial impressions? 

It is easy to insert. The springy arms on the clip can be adjusted, and unlike my optolong L-pro, this filter doesn't fall out as soon as you move the camera! It seems to work well with an astro-modded DSLR. I used auto white balance for a change and got no odd colour casts. However, I need to play about with colour balance in the DSLR and see what happens on future imaging sessions. I think for the first time, I have gained some good contrast and colour saturation in one of my images. It certainly reduced the normal light pollution colour casts that I normally get. I read on many forums that if I was going to use it, longer exposures was the way to go with some people recommending between 5 - 8 minutes each. Given the longest I have ever imaged before now is three minutes - this is a game changer for me! A Bahtinov mask helps you get really sharp pinpoint stars and focus and of all the calibrations frames, the flats are the most important I suspect as they will correct any vignetting caused by the filter (although I couldn't see any on the finished Siril results image.) 

And finally, what do we need to know about the two images above? 

NGC 7000 The North American Nebula is magnitude +4.00, an emission nebula in the constellation Cygnus and close to the bright star Deneb. The nebula covers an area x10 the size of the full moon and was first discovered by William Herschel in October 1786, from Slough! When light pollution was obviously not an issue! 

It is a huge interstellar cloud of ionised hydrogen and the shape we see from earth is caused by a band of interstellar dust that lies between it and our planet - this dust absorbs the light of stars and the nebula itself and somehow causes this shape to materialise to our vision.  Can tell I'm no astrophysicist can't you! 😁

The portion of the nebula that represents Mexico and central America is known as the Cygnus Wall and is an area of concentrated star formation. 

From us to the nebula is around 2,500 light years. 

So why do we see red? The hydrogen alpha area shine because their hydrogen gas has been ionised by UV radiation from a nearby hot star. For a long time it was thought that this was due to the proximity of Deneb, but not so! Its surface temperature is only 8500K. A star with at least a surface temperature of 35,000K is required. Deneb is not hot enough and too far away from the middle of the nebula complex.

So, where is the UV coming from? There is a star off the 'Florida' coast area of the nebula which may be a contender. It appears small and dim from Earth because it is behind the nebula but it is closer than Deneb and its surface temperature is 40,000K. Ideal! 

And IC 5070 The Pelican Nebula? 

Tricky to discern but I have circled it above. You will need a little imagination here! Early astronomers thought the nebulous gas emissions resembled a pelican! Nope! Me neither but hey there we go! 

Anyway, it is an area of very intense mixed star formation and gas cloud formation and is highly studied by modern astronomers today. Light from energetic young stars are slowly transforming cold gases to hot ones, so causing an ionised front to slowly advance outwards. 

IC 5070 is divided from NGC 7000 by a dark dust molecular cloud area. 

Still can't see the Pelican? Look for a dark dust cloud eye and then a long bill. The bright front of ionised gas curves away forming the head and the neck. 

Nope, me neither! And normally, as a geographer, I am really good at this 'spatial awareness' malarkey! 

Technique - Lost in Space and Meridian Flips

First visit to this astronomy/astrophotography blog? Well, firstly a warm welcome to you and thanks for stopping by. After reading this post, if you want to find out more about me and this blog, why not visit my introductory page at https://undersouthwestskies.blogspot.com/2025/01/welcome-to-my-new-astronomyastrophotogr.html You can also browse other posts by using the search bar or the blog post list on the right hand side and I'd really like to hear from you via the comment boxes. Drop me a tip, an observation or a question. Take care and clear skies to you. Steve

 Astrophotography is a funny old game isn't it. Take last night. Target IC 4604 - The Rho Ophiuchi complex. 

My best ever polar alignment and set up times. A clear sky, faint breeze and a 37% moon. The tide almost in and breaking over the rocky foreshore below the car park. The distant rhythmic flash of the Eddystone Lighthouse and far out in the English Channel, lit up ships passing in the night. 

ISO 800, 240" x 20 plus calibration frames. My little radio tuned to Radio Four and then The World Service. My primus stove hissing and bubbling away away when I felt the need for a warming cuppa. 

Astrophotography and astronomy have taught me much over the last few years about the night sky, how to use my cameras, mounts and telescopes/lenses; and of course imaging techniques. A newly found passion for astronomy, astrophotography and art! And all the time, I have been developing my scientific knowledge, use of technology and problem solving thinking. My son-in-law has even ignited within me an interest in 3D printing and the potential it has for creating little helpful bits and pieces for my various astronomy/astrophotography rigs. 

As a person, I have developed more. My patience is much better! My concentration and focus back to pre-retirement levels! And my blood pressure? So much lower! Out at night, under the stars, I am relaxed, pondering, reflecting, asking some big questions, just tuning in to a radio programme I wouldn't have likely heard had I not been up at that hour! 

My friends would say that I've become even more nerdier than I was and that isn't a bad thing at all. I can chatter away about the night sky forever! 

But then it isn't all rosey is it! 

I keep 'hitting a wall!'

One wall is using SIRIL and Generalised Hyperbolic Stretches. I have watched all the Youtube videos. I've taken notes. I have practised and practised - to no avail. I am still none the wiser! 

Another 'wall' is using the ASIair plate solving.  

How did I miss Rho Ophiuchi? I mean how? On my screen in plate solving it was clearly identified and central. When I did the sky atlas stuff - it synched correctly. 

But, as you can see, all the bright cloud colours - where are they? I missed my target! By quite some way! Unbelievable! I am laughing about it - serves me right and a lesson learned. Check that I have the right co-ordinates in RA and Dec! 

Plenty of 'cloud and dust' stuff

ISO 800  240" x 20 

20 of each calibration frame

Canon 800D, Zenithstar 61ii with field flattener 61A, EQM-35-Pro mount, ASIair mini, RVO 32mm guide scope with ZWO 120mm mini guide cam, Celestron Lithium Pro battery pack 

Processed in SIRIL, GraXpert and Affinity Photo. 

If you can identify where in space I ended up in this shot, I'd be grateful! 

Conclusion 'Lost in Space' somewhere! 😕😩😆

Meanwhile here is my third 'wall'. How do you perform a meridian flip on the EQM35PRO using an ASIair mini? 

I thought I had the right settings last night and it sort of performed a flip but the cables twisted and wrapped themselves around the mount and so when guiding restarted it was shambolic. I ended up doing a manual meridian flip; after I had unplugged various cables to ASIair mini and my DSLR. That of course meant rebooting everything and doing a new polar alignment. 🙄

It is hard work being a newbie and novice isn't it 😉😆

If your gear hasn't don a meridian flip yet and you are using guiding with an ASIair - here are two helpful videos that explain the process

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

First visit to this astronomy/astrophotography blog? Well, firstly a warm welcome to you and thanks for stopping by. After reading this post, if you want to find out more about me and this blog, why not visit my introductory page at https://undersouthwestskies.blogspot.com/2025/01/welcome-to-my-new-astronomyastrophotogr.html You can also browse other posts by using the search bar or the blog post list on the right hand side and I'd really like to hear from you via the comment boxes. Drop me a tip, an observation or a question. Take care and clear skies to you. Steve

 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

First visit to this astronomy/astrophotography blog? Well, firstly a warm welcome to you and thanks for stopping by. After reading this post, if you want to find out more about me and this blog, why not visit my introductory page at https://undersouthwestskies.blogspot.com/2025/01/welcome-to-my-new-astronomyastrophotogr.html You can also browse other posts by using the search bar or the blog post list on the right hand side and I'd really like to hear from you via the comment boxes. Drop me a tip, an observation or a question. Take care and clear skies to you. Steve

 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 

Imaging session - A spring mission to image globular clusters

First visit to this astronomy/astrophotography blog? Well, firstly a warm welcome to you and thanks for stopping by. After reading this post, if you want to find out more about me and this blog, why not visit my introductory page at https://undersouthwestskies.blogspot.com/2025/01/welcome-to-my-new-astronomyastrophotogr.html You can also browse other posts by using the search bar or the blog post list on the right hand side and I'd really like to hear from you via the comment boxes. Drop me a tip, an observation or a question. Take care and clear skies to you. Steve

 Globular clusters, the ancient stellar cities of the universe, formed just after 'The Big Bang'.  I can't remember where I read this but I was instantly hooked!  

They are beautiful objects to photograph and observe. highly packed spherical agglomerations of stars, circular or oval in shape, they can look like spilt sugar on a black cotton table cloth; not that I have been many places where black tablecloths were de-rigours. 

William Herschel used the name 'globular' first - from the latin globulus meaning small sphere apparently. The immense density of stars within globular clusters means that they remain bound together irrespective of whatever gravitational disturbances from the milky way or gaseous drag is occuring in the immediate galactic neighbourhood. This brightness and density means that globular clusters have a high surface brightness and so some can be easily seen through binoculars and small refractor scopes, even during moonlit nights! 

Reading an article in an astronomy magazine recently, (I can't remember which one but it would have been either Astronomy Now or The Sky at Night - the only two I tend to read when I can), that globular clusters can be classified - The Shapley-Sawyer Concentration Class -  a 12 step classification of the relative density of the core. I = high concentration of stars. XII = almost no concentration towards the centre! 

I have been focused in recent weeks on imaging M13 in Hercules. 25,000 light years away, at a magnitude +5.8, if you are in a truly dark site like the Elan Valley, you have a good chance of seeing it with the naked eye on a moonless night. Edmond Halley who discovered it in 1714 said "this is but a little patch, but it shows itself to the naked eye when the sky is serene and the Moon absent". 

How can you find M13? 

M13 sits just outside the largest edge of the keystone asterism in the constellation Hercules.  Use the stars Vega and Arcturus to lead your viewpoint to this keystone star pattern - a large uneven square of four stars, found about a third of the way from Vega to Arcturus.  M13 will be a third of the way along the longest edge of the square between the stars Eta Herculis and Zeta Herculis. 

What equipment have I been using to image M13? 

• Zenithstar 61ii with field flattener
• Canon 800D astro-modded DSLR
• ASIair mini
• ZWO 120mm mini guide cam
• RVO 32mm guide scope
• EQM-35-Pro mount and tripod
• Celestron Lithium Pro power tank
• small power bank to power dummy battery for DSLR

What are my 'beginner tips' for shooting globular clusters? 

The great thing about globular clusters are they make decent targets for astrophotography during moonlit nights. We are aiming for the following: 

• sharp images with pinpoint stars 
• a good halo of stars around the core
• no blown out stars or oversaturated ones
• no blown out core

I did some reading before hand and most tips I found stressed the following. Firstly, and counterintuitively, keep your exposures low. Go for shorter exposures but more of them to get the integration time. Several people recommended bracketing shots at different ISO's first; followed by taking exposures at 10, 15, 20, 25 and 30".  Compare the results and pick what best works for you and your shooting conditions. 

Secondly, pay real attention to your FWHM settings! Yikes - my what? Your Full Width, Half Measure. I had to do some reading around this subject! Essentially, at its simplest, if I understand this correctly (how many caveats can I put in here) - FWHM is to do star focus quality. A star has a bell shaped profile. Using a bahtinov mask and the guiding software of your choice, you are aiming to get your stars as sharp as possible - the lowest FWHM. Basically, the lower the star value - the more focused it is. 

Stressful reading was that! 

So what settings were recommended? Well, how long is a piece of string? 

I've put the settings I used below the two images I have taken thus far and we can do a comparison in a minute.  Many on astrobin, cloudy nights and stargazers lounge (if you haven't come across these forums, look them up because I cannot recommend membership of them too highly for beginners to astronomy and astrophotography - members are so knowledgeable and generous with their advice), suggested starting with 30" and an ISO of 800. Most agreed that in terms of integration time, 45 - 90 minutes would be plenty enough.  many also suggested using a delay between each of your images of around 8 - 12" to allow your sensor to cool. This will help reduce the noise in the final stacked image apparently. 

So, there we are. Some beginner tips for imaging globular clusters. Here are my first images: 

These two images are the same data but processed slightly differently. I'll do another post on how I processed them in SIRIL when I better understand what it is I am doing

The acquisition data for the photos is as follows: 

From my back garden with moon at 35% in a Bortle 4 area

ISO 800, 120" x 30

You can see how that too long an acquisition time has resulted in the core being blown out! 

For my first effort at a globular cluster, I'm quite pleased with these. Not bad, not bad at all but plenty of room for improvement. 

So, what is my post editing workflow for the above images? 

Firstly, I used SIRIL, GraXpert and Affinity Photo. 

My aims: to enhance the colours and contrast; to manage star appearance. 

Here is my workflow. Remember, I am a beginner like many of you and I am still getting to grips with these editing programs. I am using siril version 1.2.6

1. Stacking of Lights and calibration frames in SIRIL to gain results file
2. Siril - open results file - select 'histogram' on bottom menu - right click on image and CROP. Save as resultscrop.fits 

Next open this resultscrop.fits file in GraXpert

1. background extraction (at 15% in bottom menu and smoothing at 1.0 using AI
2. save as 32 bit fits file  resultscropBge or some such name

Return to SIRIL and open this new image

1. image processing - star processing - click on cog icon
2. now click on stars icon - tick amplitude box - enter new values into amplitude boxes (I use 0.1 to 0.7)
3. click star icon - a list of stars should appear in the dialogue box - keep this box open - drag it to one side
4. image processing (top menu) - deconvolution - PSF from stars - generate
5. In the PSF box - the star should be within the box with black space around it - if the star is going outside the box alter the PSF values by increasing them - keep generating and altering the values until the star generated fits within the box with black around it. 
6. Close the PSF box that you dragged to one side
7. On remaining dialogue box open (the deconvolution box), experiment with the iterations gradient settings - and when happy - click apply
8. image processing - colour calibration - PCC
9. image processing - green noise removal
10. image processing - star processing - starnet++ removal
11. load the starmask result image (for globular clusters ignore the starless image that has been generated - we don't need it) 

Move back to GraXpert

1. open new image - the starmsk image just generated in SIRIL
2. now complete a denoise (using AI) 
3. save as 32 bits fits file

Return to SIRIL and open the denoised image

1. Check that you have image in Linear mode on bottom menu.
2. image processing - GHS histogram stretch - take the local stretch intensity slider across to max
3. use mouse to zoom closer into the cluster on the image
4. now move stretch factor slider on GHS box across to right until stars are just appearing - apply
5. image processing - GHS histogram stretch 2 - Local intensity stretch slider 2/3rds way across to right - now apply tin amount of stretch slider - zoom into image to look for artifacts in surrounding stars - move slider back to eliminate these - ensure not blowing out the globular cluster core - click apply when happy
6. you can apply a saturation stretch now - top right hand corner menu on this second GHS histogram dialogue box). Do very tiny adjustments to saturation
7. save as tiff file if opening in affinity photo 

Now load up the above completed image into affinity photo 

1. I open the image in camera raw editor and then make subtle edits. be prepared to mask the core so you can work on the background first; and then the reverse, masking the background to work on the core

I hope this helps you get started if you are still getting to grips with SIRIL like me. Let me know if you have better tips for editing globular clusters. Share them in the comment box below so that we can all learn and grow further together.

As always, have fun, stay safe out there and clear skies

Steve 

PS:

Here is my latest GC image - M92

The same image data. The image above is a cropped in version of the image below

Processing data: SIRIL, GraXpert and Affinity Photo - as described above

Capture data: ISO 800, 30" x 120 (One hour integration) and 20 of each calibration frame. 

Moon at 93% full. Bortle 4 skies 

Equipment used: Canon 800D, Zenithstar 61ii, EQM-35-Pro, ASIair mini, ZWO 120mm mini guide cam with RVO F/4 32mm guide scope

Another globular cluster from the constellation Hercules. Magnitude +6.44, it was discovered by Johann Bode in 1777 and was then independently rediscovered and catalogued by Charles Messier in 1781.  26,000 light years away, it is smaller and fainter than its neighbour M13.  Its true diameter is around 100 light years with a luminosity of 150,000 sun's; nothing to worry about but it is approaching us at around 112 km/sec. 

M92 is believed to be exceptionally old, around 14 bn years, almost as old as the Universe itself. It contains around 300,000 stars and the predominant elements within it all are helium and hydrogen. Hence it is a metal poor cluster. 

A fun factoid - here we go - the north celestial pole will come within a degree of M92 in about 14,000 years time.  Every 26,000 years the Earth completes a precession of its axis and during this cycle, the pole moves closer to M92. M92 was last a pole cluster back in 10,000 BC. 

Anyway, back to my processing of the data - its not bad for one hour. I need to sharpen up the images; sharpen up the star edges - I think they are a bit soft. I need to sort out the core as well - its a bit blown out. Perhaps doing some masking to reduce colour saturation of the background as well. 

I know WHAT might need doing. Knowing HOW to do it is an entirely different matter.  It's hard work this post editing malarkey. I may have said this before? 

Equipment - Another successful trial night with the EQM35 PRO and the Astro Essentials Right Angled Eyepiece for Polar Scopes

 Why didn't  I  get  one before? 

An Astro Essentials right angle polar scope viewer! Possibly the best invention since sliced bread. Total game changer. From nothing to shooting M13 again in thirty minutes. My fastest set up time ever on anything astrophotography or astronomy related. Well chuffed. I actually completed polar alignment on the ASIair within 2' 05'. A personal best! 

https://www.firstlightoptics.com/adapters/astro-essentials-right-angled-eyepiece-for-polar-scopes.html

Out in the back garden peace is beginning to descend. Traffic noise from the valley below is lessening as midnight approaches. Just a few boy racers with their supped up cars disturbing the nocturnal tranquility.  The distant rumble of the late night London train as it passes through the cutting and under the small road bridge.

As I sit at my garden table, mug of warm  tea alongside my tablet, bats swoop overhead and frogs croak up  by the terrace pond. Distant foxes cry out, a startled pheasant clatters through the woodland shrubbery. I am reassured by the rhythmic click of my camera shutter and the tiny periodic gear clunk from my new new  mount.

A sequence of 60 x 60" shots at ISO 800 on my zenithstar 61ii. The rig is on my lower lawn and I am sat on a bench on the little deck  below it. Beyond up the steep garden  is our little woodland heaven, trees silhouetted against the night sky and its very faint orange light pollution glow. A bortle 4 rural-suburban sky. Arcturus is almost directly above me to the east.

Guiding is good. I'm getting the hang of ASIair management. RA average 0.80. DEC 0.73. I have worked out how to stop the celestron lithium pro power-tank from sliding down the tripod leg.  And the right angled polar scope viewer, combined with my MSM laser pen that attaches to a polar-scope..... game changers. Tonight it took 3 minutes to polar align the mount using the illuminator and a mere three minutes to reconfirm it in the ASIAIR. That alone normally takes me ten minutes. 

£79 for the viewer. Worth every penny! Why didn't I get it right at the start of my astronomy/astrophotography journey? What a muppet eh?