Sunday, 27 December 2020

M1 - The Crab Nebula

M1 - The Crab Nebula

In what might turn out to be the last post of 2020, I thought I would round off the year with an effort on M1, The Crab Nebula.  The Crab Nebula is a supernova remnant found in the constellation of Taurus.  It's quite small compared to many other imaging targets, but it's also visible with a decent pair of binoculars or telescope.  The challenge with imaging this particular nebula is to try and tease out the detail within the nebula.  Undoubtedly, a longer focal length telescope will help with this but I need to make do with my 80 ED-R.

I've also made some changes to my imaging set up to try and get the best out of it.  Since I bought the Hypercam 183c, I have just been using it connected to the telescope sometimes with the reducer, and sometimes without.  To get the best out of the camera and telescope combination, I needed to introduce some spacers between the camera sensor, and the telescope.  In theory, this should deal with the 'stretched stars' around the edges of the full frame, in particular the corners.  The correct spacing needs to be very accurate though.  So, I have introduced a 15mm spacer, a variable spacer and a filter drawer into the imaging train.  Bearing in mind, this is the first image with the new spacers in place, I quite pleased with the result, although I think I still need to make some small tweaks with the variable spacer.  That's for another time though.

Finally, before I move onto the image itself, I have also made an experimental change with my pre-processing workflow in PixInsight.  When I first started using the software, I initially used the Batch Pre Processing script to help pre process all my raw light, flat and dark files.  As I got to know and use PI more, I moved onto manually performing the calibration steps to try and achieve better results.  Recently though, I once again have started to struggle with dark from subtraction from my light frames meaning that I am still getting the sensor interference appearing on the right side of the final image.  Since I put my workflow together, numerous enhancements and updates have been released for PI and I now think that there are some additional settings which I need to find out about to help removing this phenomena fully again.  One of the improvements which has been introduced is a new script called WBPP, or Weighted Batch Pre Processing.  Very similar to the original BPP script, it's had some improvements of it's own, so I thought I would give it a go.  I'm really pleased with the result.  The resulting image it produces once again has no sign of the sensor interference.

So, onto the images themselves.  I've produced 2 images of M1.  The first has been processed in PI using PixelMath to help develop the colours of the supernova remnant a little further.  The second image is a cropped version with the background stars removed using he StarNet tool in PI.  Both images were then lightly processed in GIMP.

Finally, thanks to anyone who has given their time to read through my ramblings over the last 12 months.  Feel free to subscribe to my blog if you wish.  You'll get an email anytime I post something.  Have a great and more importantly, safe new year and I will be back in 2021 with more astro related drivel :-)

Thursday, 24 December 2020

My Top 5 of 2020

 My Top 5 of 2020

What a 12 months it's been.  A great year for space science, space travel and amateur astronomy.  2020 has seen some fantastic things happen like the first crew dragon capsule to meet up with the ISS and China performing lunar missions.  It has also seen some sad things like the demise of the popular Arecibo observatory and also courted with controversy with the first formation of a satellite constellation.  But in terms of my astronomy activities, it's been quite some year with unexpected opportunities and other opportunities taken away.  So, in reflection I've put together my top 5 highlights of this, the most challenging of years.

5.  The Pier Goes In

It was long an ambition to get a permanent set up for my kit.  Moving house in recent years provided me with that opportunity, and with the construction of the observatory over a year ago I finally had chance at the start of the year, to get a pier built and put in place.  It was the last piece of the jigsaw which allowed me to get everything set up and in place.  It has proved to be a fantastic timesaver and mean that I can now be switched on an imaging in as little as 10 minutes.

4.  Awesome Astronomy Does Live Streaming

2020 Was full of firsts.  My next highlight was provided by one of those firsts, and that was the live streaming of the Awesome Astronomy recording of one of their podcast episodes.  At a time when people were restricted in what they could do, it provided an excellent distraction from day to day life.  It provided an excellent opportunity to link back into the astronomy community and see some familiar faces.

3.  ISS Solar Transit

Long have I seen images which fellow amateur astronomers have taken of the Sun with a silhouette of the ISS passing across the front of it.  I have always wanted to attempt to capture an image of it myself, but hadn't made time or opportunity to do it.  Towards the beginning of Summer, I did a piece of research to find out when the next transit path was and found that there were 2 transits in the coming days.  The first attempt was a fail.  I just didn't get a quick enough frame rate to capture the image.  The second attempt a couple of days later was almost scuppered by cloud, leaving me no time to get a good focus.  However, I succeeded in capturing my first image of an ISS transit.

2.  Dither

It seems an odd choice, at first, to call this a highlight of my year, but I firmly believe that learning how to incorporate this into my image capture process has made, and will continue to make, a big improvement to my images.  It wasn't until later in the year, quite recently in fact, that I adopted the technique, so I haven't produced many images at all using the dither function, but it is undeniably well worth doing.  And what's more, it's so easy to do.  This was my first proper image produced using the dither function, and while it's not especially amazing, I am really pleased with it.

1.  Comet Neowise

Without doubt, the big thing which captured the public imagination this year was the first naked eye comet to be widely visible since the 90's.  At a time when we were all being encouraged to take some exercise, but avoid contact with everyone else, Comet Neowise proved to be an excellent opportunity to get out of the house. Even the weather decided to cooperate.  The comet was visible back in the Summer, so it meant that it called for some late nights to be able to see it at it's best.  It felt somewhat adventurous, taking off on my mountain bike at sunset with my camera on my back heading out to a farmers field and then returning in the small hours when all was dark.  But what it lead to was a collection of images which I was really pleased with.

2020 has been full of challenges, and 2021 is going to be much the same, but there is so much to look forwards to.  Clear sky permitting, I shall be taking every opportunity to image and observe as I can this year.  I hope to get back to a star part or two and who knows what else I am going to discover.
Thanks to anyone who has read my blog over the last year, or ever actually.  Have a great Christmas and New Year.  Here's to 2021!

Thursday, 17 December 2020

NGC 7331 - More than meets the eye.

 NGC 7331 - More than meets the eye.

Greetings!  Sitting here listening to the latest Awesome Astronomy podcast, it's time to put fingers to keyboard and put together a post about my most recent image.  In truth, I wouldn't post this image normally.  It's quite poor in quality because of the conditions that the data was gathered in.  The night of the image capture was back at the start of November when the initial dark sky quality was not too bad, but as the evening went on the sky filled with a thin mist until a point where the only starts visible were at azimuth, directly overhead.
My target for the night was NGC 7331, which I picked out of one of my astrophotography books.  Also known as Caldwell 30, it is an unbarred spiral galaxy in the constellation of Pegasus.  So, why did I decide to post this image anyway, despite it overall being quite poor.  Well, when I started looking more closely at the image, I realised something which I hadn't appreciated when I first chose the target and that was the number of galaxies that could be seen in the image in poor conditions with just 3 hours of exposure and a small 80mm refractor.  
At a relatively quick glance when zoomed into the image, I picked out at least 24 other galaxies, aside from the main target in the centre of the image.  To help point them out, I have added red lines pointing at each galaxy or galaxy cluster.  It's amazing to think that these are just the ones I can see at a glance.  The numbers of galaxy in the image's field of view probably is much more.

In case you can't see the galaxies pointed out, I've taken zoomed in image snips of many of them to illustrate what's visible in a full resolution image.  Perhaps my most favourite one is the last but one image which shows a perfect face on spiral galaxy in which the arms of the galaxy can clearly be defined.  In the main image, it's in the bottom right corner.

So, an image and a post more for posterity than publishing on the blog, but it's a great reminder that when imaging, it's always worth having a scout around to see what else is lurking around the main target.  

Sunday, 22 November 2020

Dither Fish

 Dither Fish

Recently I took the opportunity to take advantage of around 4 hours of clear sky here in Herefordshire.  I didn't have much planning time, so I opted to revisit a target I first imaged back in December 2019.  This was back when I just started using my Altair Quadband filter and I was sticking religiously to a tried and tested processing workflow in PixInsight.  As well as learning a bit more about the filter and processing, there has also been one other big step forwards with my data collection.  In my last few outings, I have started using the dither feature in SharpCap pro.  In my traditional way of imaging using SharpCap, I couldn't dither as the feature is only available when using the Live Stack feature.  However, I read that you could get around this by simply saving each of the subframes by clicking on a tick box in the Live Stack feature.  This sorted the sub frame saving issue which meant that I could then utilise dither when guiding.  I'll post more on the technique and settings I use another time, but for now, let's take a look at the results.
The two images below are cropped around the main part of the target showing a good proportion of the nebula itself, but also so well defined background.

The first image is quite noisy throughout the colour and background.  You can also just about make out that there seems to be a pattern where the noise appears to run diagonally top left to bottom right down the image.

The second image is part of my most recent image.  It shows the same cropped area, but notice the significant reduction in noise between the images.  While this is undoubtedly partly down to improved processing, the use of drizzling during the data gathering phase has made a huge difference, completely removing the diagonal noise patterns throughout the image.

IC1795 - The Fish Head Nebula

Having taken that big step forward and produced notable improvements, I shall undoubtedly dither on all my deep sky imaging from now on.  This only leaves me one thing left, and that's to show off the finished final image.  I seem to have a little problem with sensor noise coming through on the right side of the image.  A new dark library would of probably sorted that out.  Nevertheless, I'm still very pleased with this dithered quiet fish head.

Tuesday, 17 November 2020

Autumnal Trio - M57, M53 and NGC 6888

 Autumnal Trio - M57, M53 and NGC 6888

Back in September, we had a run of poor weather which meant I had the chance to revisit some old data and apply some new processing techniques.  Though astrophotography in my opinion is always going to be a case of continual refinement, it's been nice to get the chance to collect some new data.  Generally speaking, weather conditions have been a bit rough, so I haven't been able to do as much as I would like to do and it's just been a case of grabbing any opportunity I can without much in the way of thought or planning.  I've also come across a few bugs in my set up which has lead to a bit of frustration, knowing that time has been precious but needing to sort out these issues before I could proceed resulting in bit of a change in the way things are connected in observatory.  More on that later.  

M57 - The Ring Nebula

The first of the images I've had chance to put together is of this Autumn classic, the planetary nebula M57.  It's in the constellation of Lyra and during late Summer into early Autumn, can be found almost direct overhead as it gets dark.  While small, it is quite bright, so on this particular night in October, after addressing a few technical gremlins in the observatory and with cloud forecast, I couldn't spend hours and hours collecting data.  I was limited to around 90 minutes or so, but as you can see, that was more than enough to get some good data and colour using the Altair 183c Hypercam.  Through the eyepiece of a telescope, this target can easily be missed, not because it is that dim, but more often because it a quite small.  At higher magnification, you do lose a bit of brightness, but the ring can be resolved.  With the use of a UHC filter to help darken the background sky, the nebula can really be pulled out from it surroundings, but it will still only be visible as a wispy grey ring.  It's still though, an absolute favourite target for my observing list at this time of year.

M57 - The Ring Nebula in the constellation of Lyra.

  M33 - The Triangulum Galaxy

Given the choice of galaxies to image at this time of year, M33 has got to be one of my favourites ahead of some of the more traditional and well known galaxies of Andromeda and the Fireworks galaxy.  It frames well, responds very well to OSC imaging cameras and is well positioned throughout the night.  As is the case with most targets, the more data that is collected, the better.  This time around, again battling against deteriorating conditions, I was fortunate to get around 2.5 hours of data on it.  I wanted more.  I wanted way more, but cloud and bonfire night got in the way.  It wasn't until post processing did I really appreciate how much the sky quality decreased through the evening as more moisture condensed in the atmosphere combined with air pollution from fireworks and bonfires.  In the end, much of the data towards the end of the imaging was useless so I had to bin it.  Nevertheless, playing more with some new to me techniques of processing in PixInsight, I was able to pull out a pleasing amount of colour and data from the subframes I had collected.
Compared to my last effort, It's good to see that in my opinion, my imaging and processing skills seem to have improved somewhat.

M33 - The Triangulum Galaxy

NGC 6888 - The Crescent Nebula

This is a fascinating nebula.  NGC 6888 is found in the constellation of Cygnus, and it is one of those nebulae which when observing, often gets overlooked as it's tricky to pick out unless you're using some sort of massive light bucket and filter.  Imaging wise though, it's a different story.  Capturing a reasonable amount of data for the image is fairly straight forwards.  However, this truly is an example of more data the better the image.  The initial shape of the crescent is the first part of the nebula to be revealed.  However, I don't think OSC imaging really does this target justice.  To really bring the full extent of the nebula structure would mean adopting mono imaging techniques with filters and perhaps putting hours and hours of time into each channel.  What amazes me is that this nebula was first discovered back in 1792 by William Herschel using the equipment of the day.  Though he would of had far less light pollution to deal with (one assumes), he would of been using inferior quality optics, small aperture and no filters.
This data was obtained on November 6th. Unfortunately, the bonfire night antics this year seemed to spill over into a 2nd, 3rd, 4th and even a 5th night.  I knew I needed as much data as I could to help bring out more of the structure within the crescent shape, so in the creation of this image, I did include some poor quality sub frames which I would of otherwise ditched.  One day, I would love the opportunity to collect perhaps 6+ hours of data, but this time I've made do with around 2.5 hours or so.

NGC 6888 - Crescent Nebula

Bugs and Gremlins

For some reason following on from Summer, I have had a couple of issues with frames being dropped from the camera while imaging.  Since buying my quadband filter, I've been trying to adapt my imaging techniques to make the best I can of the filter.  Some of these changes have included using SharpCap smart histogram to analyse the optimum camera settings for me to use.  What's become evident to me is that I needed to increase my exposure time from 2 or 3 minutes up to around 10 minutes, if SharpCap is to be believed.  I've tried to adopt these new settings, but I noticed not all the sub frames were consistently being written back to the NUC PC in the observatory.  Now, there are a plethora of reasons why this might be the case.  The Hypercam I have is one of the earliest versions, so it has no on board memory for buffering.  But theoretically, given that it's been working predominantly fine, I can't think of a reason why this should be the root cause this time.  Secondly, it's a USB3 camera plugged into a USB3 port on the NUC PC and it's commonly advised by Altair, that the length of the USB3 camera used is kept to a minimum.  I use the cable supplied with the camera, so that shouldn't be causing the issue either.
Considering these requirements, I was left with two easy options to try.  I had a bit of a change around on the observatory pier.  Originally, I had 2 3 pin power sockets, the NUC and it's power supply and the all the associated cables coming from from the mount, cameras and controller all contained within one plastic weatherproof box mounted on the pier.  I wanted to change the USB3 port the Hypercam was plugged into on the NUC which needed a reworking of the cabling.  To help make room, and potentially remove some strain off the cables and ports, I took out the 2 3 pin sockets and put them elsewhere on the pier.  The other thing I did was to remove a connection to a spare USB2 hub which I also had on the mount.  Strictly speaking, I don't need this, but it makes life a bit easier when it comes to transferring data to USB stick at the end of an imaging run. 
The second thing I have applied is a simple driver update.  I noticed during my checks that the driver I was using for the camera was from early 2018.  Usually, manufacturers will update drivers as time goes on, especially if they still use those same drivers for their most recent products.  I couldn't get the camera drivers from Altair on their own, but they do come bundled with their imaging software, AltairCapture.  So, I downloaded the latest version of the software and updated my installed version.  I was pleased to see that the driver was also updated with a 2020 version.  In some initial testing when taking some dark calibration frames, it was good to see that only a single frame was dropped right at the start of the run.  This is often the case though as I will make last minute tweaks to camera settings while the first from is being captured.
Hopefully this work has got rid of the bugs and gremlins which have appeared.  Alas though, I will need some clear nights to get everything up and running.  

Wednesday, 30 September 2020

NGC 281 3 Ways

NGC 281 3 Ways

 After a summer hiatus, I've got my astro mojo back.  In my last post, I showed off a series of images taken during a recent run of good weather.  Even though Autumn is well and truly here along with the wind and rain, I've been busy on other astro related projects by learning about more processes and techniques used in PixInsight.  
I've spent a few evenings looking around YouTube and other blog sites to see what other techniques people are using and look to introduce some of them into my own workflow.  The newest technique I've tried to introduce is splitting the raw stacked image into 3 RGB colour channels.  In theory, it allows me to work on the three channels individually, before re-combining them to form a colour image.  One day, I will put an example of my workflow in a post, but I need to improve it significantly first.
One of the easiest ways of comparing processing techniques is by starting each workflow with the same original data.  I chose NGC 281 which is a lovely nebula which sits comfortably in the frame of the Altair Hypercam 183c used in conjunction with the 80 ED-R telescope.
Onto the images.  This is the first image processed with my regular workflow for a straight forward OSC camera.

Now it's time to start playing.  To be honest, I can't remember all the different parts of the workflow I used for this next image.  What is certain is that there is still a load of noise and other work to include, but as an experimental image, it's pleasing to get some other colour out of the data, and play with contrast and saturation settings a bit more.  Remember, this is from exactly the same raw starting image as the one used to create the image above.

Recently, there has been a new update released for PixInsight.  It includes the StarNet++ tool which used to be a separate import.  Even though I haven't managed to get it to produce a really clean result yet, it still produces some interesting results.  I think it perhaps will work better on targets that don't have quite so many stars but this next image gives an idea of what it could do.

And there you have it.  It's always good to show some experimental images from time to time.  I wouldn't call either of these last two images anywhere near complete, but definitely encouraging signs of what could be achieved.  Happy days!

Thursday, 24 September 2020

Lockdown Astrocamp 2 - Another One Gets Away

 Lockdown Astrocamp 2 - Another One Gets Away

Earlier this year, I wrote about missing out on one of my highlights of the year, the Astrocamp star party.  Though gutting, cancelling it was the sensible, and only real choice.  Possibly through rose-tinted glasses, everyone looked forward to and hoped that the second scheduled event in September would go ahead.  Alas, continued developments have conspired against the organisers and us, to leave little option but to pull the plug on the Autumn event too.  But it takes much more than a microscopic organism to stop us from doing any astronomy! 
Readers of my past posts will know that we often do battle with the weather at Astrocamp.  More often than not, not much astronomy gets done but everyone still had tons of fun.  This time, should we have all been gathered at Astrocamp HQ, we would of had a straight run of clear nights for the whole camp.  Typical!  So, what do you do with a few days of work, a run of clear nights and a plenty of time?  Get out there and make the most of it of course!

What was it I did before?????

After a comparatively short amount of time out of the observatory (about 2 or 3 months in total) because of weather and generally Summer getting in the way, it's been awesome to get back in there again.  The first clear night was always going to be a bit of a struggle.  Trying to remember how things worked, what settings I used where. and how it all comes together was always going to tax the brain a bit.  That coupled with high cloud whipping across the sky occasionally meant that any thought of getting hours of data on a target was going to be tricky.  Best start basic and build back up I thought.  Gradually, it all come back, and I was able to get polar alignment tidied up, updates installed, get guiding going and eventually grab a few frames of a target.  That'll do for one night.

17th September and NGC 6992

Cygnus is high in the sky at this time of year, and has some truly awe inspiring targets to chose from.  Perhaps the most photographed is the Veil Nebula.  The nebula itself is a huge target, impossible to fit into a single frame of my camera and telescope.  It's obvious why people hone their mosaic skills in this area of the sky, taking sets of data from all different regions of the nebula before stitching them all together in post processing to give one image of the whole area.  I'm not at that stage yet. I wouldn't know where to start, but I did get around 3 hours of data on the Eastern Veil.  That would be good enough for me as a first serious swing at getting an image after the Summer break.

The Eastern Veil Nebula - Cygnus
Altair Astro 80 ED-R, Hypercam 183c and Altair Quadband filter.

20th September and NGC 281

After a few days of playing around with that data, and producing the image, I started to remember how far my imaging had come over the last winter.  There were two key things which I had in my mind to tackle next.  One of those was dithering.  For a quick explanation...
When a camera is taking long exposures, some cameras can produce a lot of 'noise' in the image.  It's particularly noticeable in the darker background where the image looks very grainy.  That in itself isn't too bad as you can remove it to a degree in post processing.  But, noise often appears in straight or diagonal lines across the image and I've seen it referred to in forums as 'walking noise'.  Due to it's regular direction, and frequency, it can be harder to eliminate during processing.  This is where the lovely term 'dithering' comes it.  Usually, the telescope and mount will track a target through the sky, and aided by guiding software like PHD2, the target is kept exactly in the same place in the frame for the whole time.  This I believe causes noise to appear in the same pattern for every frame being taken and when all these frames are stacked on top of each other, the walking noise pattern is formed.  Dithering combats this, so it was time for me to learn how to dither effectively.  By luck, it's extremely simple to set up within SharpCap.  A couple of ticked boxes, and a slight amendment to the way I set up my imaging runs, and I had it working.  Dithering now moves the camera on the mount a tiny amount, even just a few pixels, in a random direction in between every few frames.  It means that because the target, and therefor the background has moved slightly in relation to the rest of the frame, that the camera sensor isn't putting all the noise in the same place.  During stacking, PixInsight takes the stars in the image as fixed points, and overlays the images using those stars as reference points.  Any noise produced is therefor not concentrated in the same place every time, and therefor isn't so apparent in the final frame.  Perhaps one day I will do a more illustrative post on that, but it is a pretty basic tactic used in imaging which I should of learnt how to do and adopted from the start.
Nevertheless, dithering sussed and slightly less noisy data to process, I pointed the camera to NGC 281, the Pacman Nebula.  This is a target which I have imaged last around 2 years ago.  This was the result then:
Since then, I have invested in a new filter which isolates emissions of different light wavelengths very effectively.  It brings a whole new appearance to the final image.

Pacman Nebula - Cassiopeia
Altair Astro 80 ED-R, Hypercam 183c and Altair Quadband filter.

21st September and NGC 7635

The last night in a run of good nights for observing and imaging.  The great thing with having an observatory is that it gives me time to get everything on and imaging within around 10 minutes of opening the door.  After that, I'm free to get out the SBT (12" dob) and return to good old fashioned visual astronomy.  This time of year is awesome, especially at the moment where we have Jupiter, Saturn and Mars easily visible, with a couple of other planets visible if you know where to look.  With the Summer constellations visible for a few hours at the start of the evening, it's awesome to be able to see the Witches Broom nebula, the Ring Nebula and loads of the classic clusters.  If you hang around until the small hours, you then start to see the arrival of the more traditional Winter constellations like Orion.  I've also been lucky enough to provide some neighbours with a very quick whistle stop tour of the sky and it's been absolutely brilliant to hear their reactions the first time the clapped eyes on Jupiter and Saturn.  Hopefully something that will stick with them all for a long time.
Back to the imaging.  This quadband filter is making a big difference to my final images and I wanted another opportunity to compare a target imaged with just a light pollution filter (which filters out predominantly sodium, leaving many other wavelengths of light through) to one taken with the quadband.  So, I  looked back through my blog, and picked up NGC 7635 also know as the Bubble Nebula which I first images around 2 years ago.  I collected a very similar amount of data (around 3 hours ish) with the same camera.  This time though, the target seems to "pop" out much better.  It's a small target in the frame, and with hindsight, perhaps I should crop the high resolution image and enlarge it a little to help bring out more of the detail.  The new filter does seem to being out much more red, and fainter nebulosity is definitely more visible surrounding the bubble itself.

Bubble Nebula - Cassiopeia
Altair Astro 80 ED-R, Hypercam 183c and Altair Quadband filter.

Wrapping it up.

Earlier I mentioned that there were two things at the end of Spring into Summer, that I wanted to get to grips with.  On of those was dithering.  Tick.  The other is processing data captured with the quadband filter.  I use PixInsight as my primary software for stacking and processing, but it is quite complex.  I've heard and read of many people splitting their image up and doing some whizz bang processing on the different channels before combining it all back together again to give amazing results.  The bit that I can't find is a step by step guide for that part of the process using a OSC and quadband filter.  I've got a vague idea, but nothing solid which produces the results I expect.  That's my next objective, and one that I hope to have sussed in the coming weeks.  We shall see!
Until the next time, thanks for reading, and clear skies.

Thursday, 16 July 2020

Catching a Comet

Catching a Comet

Comet C/2020 F3 NEOWISE

Some years ago, I remember standing under a clear sky on a campsite in Swansea and staring up at the site of comet Hale Bopp.  Back then, digital photography wasn't really a thing.  Camera smart phones were still some years off, and astrophotography was still really in the realms of research institutes or those who could afford it.  For the masses, you relied on visual observations and if you were interested in sketching, drawing your observations for your own records.  Some would capture the image in photos using the SLR cameras of the day.  This really wasn't that long ago.  1997 in fact.  It was haled as the best comet visible from Earth for decades.  Since then, any time a comet has come close to being visible, it has been compared to the Hale Bopp comet of 1997. Unfortunately, nearly all of them haven't lived up to expectation, especially becoming naked eye visible.  The problem is, comets are really unpredictable.  Often, they are only discovered a matter of weeks or months before they pass on their closest point of their orbit to the sun and pass their peak brightness.  Sometimes, comets don't make it past the Sun, and are torn apart and other times, they quickly fade away.
So when word started coming out of a new comet discovery came about a couple of months ago, the usual chatter of attempted predictions on it's brightness started.  Personally, I wasn't even aware of it.  That was until a flurry of social media posts and news articles started to reference it's brightness started to appear.  It was then that things started to get exciting.

Time to Image

I've never had the opportunity to image a bright comet before.  I've imaged a very dim comet through a telescope before, but that wasn't amazing.  So when I learnt that people could image the comet with a simple DSLR I put myself on a quick YouTube crash course on how to go about photographing the comet.  Now all I needed was a clear weather window, and a time when I could get out under the night sky.  For once, timing couldn't have been better!  The comet was always going to be low on the horizon.  I also had to contend with the time of year.  Being Summer time, the sky doesn't get truly dark.  In fact, astronomical darkness is still some weeks away where I live.  So, I had about an hour from around 11.00pm onwards when it was dark enough to see and image the comet, but before the comet dipped too low on the horizon.  If I missed that window, I would need to try again around 2.30am as the comet would slowly rise above the horizon again, but before the Sun would also start to rise and cast dawn daylight across from the East.
To get to a place where I could see the northern horizon would mean leaving the house and a trip on the mountain bike.  I packed up all my camera kit and tripod, fitted the bike lights, grabbed the head torch and off I went into the darkness.  
My choice of location couldn't be less glamourous.  But it served it's purpose.  I set up on the edge of crop field on the bank of the River Wye, within 30 meters of the sewage treatment works.  With the gentle hum (and the other hum) and the occasional clank as the treatment works did their job, I set up and started to do mine.  So, here we go.  A collection of images from two evenings from the same location.  All the images were taken with my Canon EOS 1100d camera and the standard lens kit that comes with it plus my widefield Samyang lens.  There were no filters used at all, and only some light touch-ups made with GIMP in post processing.  I hope you enjoy.

f/5.6 iso 3200
5 sec 180mm

f/5 iso 100
4 sec 75mm

f/5.6 iso 1600
6 sec 180mm

f/5.6 iso 3200
6 sec 125mm

30 sec iso 400

iso 1600 30 sec

Wednesday, 29 April 2020

M13 and M102 - A fine pair

M13 and M102 - A fine pair

Finally, I have got to the end of the glut of data I have acquired over the recent weeks.  Also, this will be the final instalment of the recent glut of astronomy blogs, for I have eventually caught up with all things Astro blogging on my list.  Yippee I hear you cry!  For this post, I look at two targets I imaged around a week ago.  In a break from galaxies, I look at M13, a globular cluster before moving onto M102.  A galaxy with a dubious past.
No matter what time of season it is (as in, right now, we call this time of year Galaxy Season because of the number of galaxies that can be observed and imaged with relative ease) I always keep an eye on what's next coming over the horizon.  It won't be long before we lose astronomical darkness overnight, which will mean imaging time of any use will be taken from us in the weeks either side of the Summer solstice.  So, over the next couple of months, while darkness is at a premium, we will say goodbye to Leo, Virgo and the likes, but hello to the Summer constellations of Lyra, Cygnus and Hercules amongst others.  In fact, these constellations are already putting in an appearance after midnight as they creep up above the Eastern horizon.  Hercules is the first of these to put in an appearance, rising high enough to observe and image slightly before midnight, and it is here that I looked for my next imaging target.

M13 - The Great Globular Cluster in Hercules

A favourite at star parties for observers new and old, M13 is a magnificent site in any telescope or suitable binoculars.  It's brightness and location make it easy to spot.  But, I have found that imaging this target raises it's own difficulties.  Being made of nothing but countless stars mean that focus is everything.  When we observe M13, rather than just being satisfied that we've seen a condensed blob of stars, we spend time at the eyepiece to try to visually resolve those stars.  Only then I find can we gain a true appreciation of this cluster.  The same goes for taking a picture of it.  Slightly out of focus, and you could tell what the image is of, but instead of being able to resolve as many stars as possible in the globular core of the cluster, you could end up with a blurred white spot with a few speckles of other stars around it.  However, accomplishing a good focus is harder that it sounds, especially when having to rely on manual focusing without the aid of an auto focuser adjusting itself throughout the imaging session, keeping everything as optimum as possible.
I first tried this target before I had a dedicated astronomy camera, instead using my DSLR and though back then I was happy just to get any result, I have since changed to a refractor telescope which makes focussing much better.
Can you spot at least one other galaxy in the image?

M13 in Hercules is a wonderous site at high magnification when observed through a telescope.

M102 in Draco

M102, or should that be NGC 5866?  If you take a look at the Wikipedia page for this galaxy, you will be referred to several other galaxies, including M101.  To get a partial understanding of why we have confusion, we need to have a very quick history lesson...
The targets we observe and image all have designations, or names given to them.  Targets starting with the letter M were first catalogued by Charles Messier as he went about searching the skies for comets in the 18th century.  When he identified a target, but determined it wasn't a comet, he described it, gave it a catalogue number and a position and then left it at that.  The point being that he knew if he came across this object again in the future, that he had already observed it, and therefor could just get on with the rest of his observations.
Then, along come another astronomer, Pierre Machain, who used to share observation information with Charles Messier, but he determined M102 to actually be a duplication of M101 and therefor, you could say not to exist.  Though limited because of the quality of the equipment of the day, the confusion for sets in because visually, they are very different targets.  Though both galaxies, M101 is a face on spiral galaxy, and the supposed M102 is an edge on galaxy.  It has also been suggested that M102 is actually a duplicate of one of several other galaxies listed in the NGC (New General Catalogue).  Over the years, other astronomers and professional bodies have had their own interpretation of what M102 actually was when it was first catalogued, but it's now come to be generally accepted that it was indeed different to M101, and is more likely to be what is now catalogued also as NGC 5866.
Whichever way you look at it, and whatever name you wish to give it, it provides a good challenge to image.  On images using a longer focal length which allow you to get much higher magnification, you can see the galaxy edge on, but also make out a thin dark line running through the edge of the galaxy.  While I could just about make out this line early on, unfortunately during the processing stages, I seem to have lost this detail while trying brighten the galaxy overall.

The wider field view of the galaxy.
The image below is an enlarged crop from the original hi-res image in which you can just about make out the notable feature of this galaxy.  It's still quite tricky to spot though...

Finally from me, thanks for sticking with me through this recent splurge of Astro posts.  I have finally come to the end of my backlog.  Hurrah!  There are a couple of opportunities to get outside observing and imaging again in the coming few days, but the weather has generally deteriorated somewhat compared to recent weeks.  It's back to snatching half chances to get out under dark skies when I can.  For the moment though, thanks for reading, and stay safe 😊.

Tuesday, 28 April 2020

Astrocamp Spring 2020 - The one that got away.

Astrocamp Spring 2020 - The one that got away.

Regular readers will know that after ever Astrocamp, I like to sum up the long weekend with a regular blog post.  Well, how the bloody hell am I going to pad this one out????  So, what do you do when you can't all meet up for the main event of the Spring?  Well, as it turns out, you do what every other human on the planet seems to be doing at the moment, and shift it online.

Day 1.  Arrival!

On a day where I, and people across the land, should have been arriving at camp, and setting up our tents and scopes, we were all sat at home, under lockdown conditions just like we have for over a month.  It has become the new norm.  And people seem to be coping with it in different ways.  Some better than others, but we get by.  In this particular situation, I could sit back, look at what we were all missing, and get generally down in the dumps about it all.  Or, I could pick myself up, and try to make something of it, and join a whole bunch of other people trying to make the most of a pretty glum situation.  I chose the latter!
I decided to replicate my pitch out in the back garden, and so hauled all sorts of kit out into the back garden and set it up.  OK, I admit, I had plenty of time on my hands!  In a rather bizarre way, it at least felt like camp had started.  Being surrounded by everything from a toilet tent and telescope to a water carrier, stove and slow cooker.  Mind you, I do look back at this and wonder what exactly I was trying to achieve, but it kept me amused for a while...

Over the last couple of camps, I have taken my bike with me, so I can go out for a ride during arrivals day.  A great chance to get out and usually see some of the Brecon Beacons and Black Mountains.  Indeed, this time last year, I went off on 70km ride starting and finishing at camp.  This year, I wanted to replicate this.  Fortunately, one of the few reasons we can currently leave the house is for a period of daily exercise.  So, with the Sun up and the sky blue, it was time to replicate that part of camp too!

Night 1, and people were posting images of themselves setting up their scopes in their own gardens to take advantage of some fantastic weather and clear sky.  It seems that everyone was determined to take part in some way or other, and was great to see.  For me though, the local forecast started off good, but cloud was soon to come in and obscure the stars for the rest of the night.  Unfortunate, but typical of camp on so many occasions!

Day 2. Setting the scene.

When I woke at home for the second day of my sudo Astrocamp, I thought back to how things typically look after a good night at camp.  There are relatively few things needed to make a classic night at camp.  1.  Awesome people.  2.  Clear sky.  3.  Let's call it 'socialising'...
There are certain things you will generally see at camp if you are up and about early enough.  Telescope tents covering telescopes, camping chairs, and socialising leftovers. It was time for another re-creation in the back garden, and even the customary barrel of Astrocamp ale made an appearence!

Quite what the neighbours might have been thinking , I don't know, but it was time to carry on with the rest of day 2. And that means only one thing. A trip to the café for a cooked breakfast. Yep, I re-created that too...

Day 3. Quiz time!

The highlight for many an Astrocamper is the afternoon spent at the Spiral Arms where we would usually have talks and quizzes.  We could not let the weekend go without at least having a quiz, and it also turned out to be a brilliant opportunity to catch up with everyone via the power of Zoom!  For me, this was both the best bit, and the saddest bit of the whole weekend.  Finally a chance to see everyone, and talk to everyone.  This is the part of the whole event I missed most.  A big shout out to John for putting himself forward to organise the quiz.  Such a  great way of bringing everyone together, and the uptake was brilliant.  So many familiar faces and voices.  It was just awesome to be involved.

Day 4. Time to head home, from the back garden.

The day where everyone wakes and knows the inevitable can't be delayed any further.  Time to go home.  In a scene often witnessed at camp, people start the tradition of tent wrestling as they try to get it all packed down and fitted into the bag.  Yep, I had a go a recreating this too...

Wrapping up.

When things improve.  When we get back to normal.  Two phrases that we have all heard with increasing regularity during the last couple of months.  By our very nature, we are social creatures.  We like spending time together be it in large groups or small.  The circumstances we find ourselves in at the moment are unprecedented in our lifetimes.  While we can leave the politicians try to make out that they know what they're doing, and that their course of action is the best one in the world to take, the truth is that it is down to us as individuals to look after ourselves, our families and our friends.  This weekend has shown me that in some situations, we only have ourselves to turn to, but in other situations, if we pull together, we can make the best of many things.  It's easy to become totally isolated because we don't get the physical company we like as humans, but by rolling up our sleeves and immersing ourselves in things that we can control, we can come out all the better for it.  Having contact with so many regular Astrocampers over the last weekend has been really good for the mental health and re-affirms what a brilliant bunch of people they all are.  
In years to come, I expect we will be able to read back to this blog post and wonder how we coped with it all.  It's been the weirdest, hardest and possibly most pointless and worst blog post I've ever written, but as I have always maintained, it's my way of just recording what I get up to in my astronomy activities, and if anyone else wants a nosey and a read, then great.  
Finally, when news broke that this Astrocamp had to be cancelled, everyone who had paid for their pitch had an option of either claiming a full refund, or donating the money to local business that would otherwise benefited in some way by the event taking place.  During the Zoom quiz, John announced that together, we had donated well over £2000 which was being split between the campsite at Cwmdu, the local pub The Farmers Arms and the local café and tea rooms.  A fantastic gesture by a great bunch of people which I should go a little way to supporting those businesses.
Here's to the next Astrocamp!  Stay Safe.

Monday, 27 April 2020

Welcome To My Observatory

Welcome To My Observatory

Hello, and welcome to another lockdown blog post.  Clearing the backlog generated by the opportunity to do a shed load of astronomy due to the lockdown measures coinciding with some brilliant observing and imaging weather conditions.
Back in October last year, I had my observatory built, and now I've had plenty of time to get settled into using it.  All my kit has been moved in, and I've been able to knock out images more regularly that I have ever have done before.  Actually, let me rephrase that.  I've managed to take advantage of minimum set up times, and every weather opportunity presented.  That's probably more accurate.
Anyway.  I've posted a couple of pictures here and there of the observatory, but nothing that really takes a close look at it.  So, here by no popular demand whatsoever (actually, two requests), I've taken a step into the world of YouTube and put together a quick video tour of the finished product.

Keeping, this post short and sweet, that's a wrap for this one!  I'm off to start processing more data which I have gathered in the last month or so.  The backlog of posts is finally diminishing, but I'll keep going until I'm all done and I have to wait for the next batch of good weather so I can start astronomising once again.  Still to come this week, I'll be posting about a couple more images I've taken of a couple of Messier objects, and also Astrocamp on Lockdown!
Stay safe everyone!

Sunday, 26 April 2020

M51 - Snatched From The Jaws Of Defeat

M51 - Snatched From The Jaws Of Defeat

Welcome to the latest in this series of catch up blog posts.  I've managed to cram in so much astronomy this Spring that the topics I feel that are worthy enough to write a few lines about, are stacking up!  So, let's continue through this backlog and get on with today's post.
This post hails back from a week ago, when I snatched another chance to get the observatory roof open and do a bit more astrophotography.

Target Acquired...

It had been quite a while since I last tried to image M51, AKA The Whirlpool Galaxy.  In fact, looking back through my archive, I see that it was circa August 2016 when I last collected the photons travelling from this popular target.  Back then, I was using a completely different set of equipment and techniques.  I was using a DSLR and Backyard EOS to capture my data.  The mount I used back then was a Celestron AVX mount set up in the back garden of our old house.  Processing was carried out predominantly in Deep Sky Stacker and GIMP.
I've come on a bit since then, and now use an astro dedicated OSC camera on a Skywatcher EQ6-R Pro mount permanently set up in the observatory.  All the data is captured with SharpCap Pro and processed in PixInsight.
That's enough of the tech jargon, let's move on.

Data Acquired and Processed...

Originally, I wanted to collect between 3 and 3.5 hours of light data of M51, and then all the relevant dark and flat calibration frames on top of that.  In fact, that is precisely what I did, but I did seem to hit a big issue.  As part of the processing, I look at each individual frame to see if there are any anomalies which could affect the final results.  I found loads.  Out of approximately 36 frames, 8 of them had satellite trails going through them, so I removed them from the stack.  Only after I finished this image did I learn that there are techniques within PixInsight which can deal with satellite trails to some degree.  But that's a whole new topic for another day!
Onto the stacking and calibration, where for some reason, PixInsight failed to calibrate another bunch of the remaining frames.  I tried several different ways using different settings, but not making much difference.  In the end, I had to call it quits, and just run with the frames I could use.  I was now down to a total of 11 light frames, roughly 1/3 of the total I was originally hoping for.  Things weren't looking good and to be honest, I wasn't expecting much at all.  I was staring a completely wasted night in the face.

Victory Snatched...

Even though I didn't expect much from this set of data, I wanted to persevere through to the end result.  After all, you don't learn anything by giving up half way through if something doesn't work out.  Somehow, and I'm not sure how, I managed to salvage a very reasonable picture (in my opinion anyway) of M51, and when compared to my attempt from 4 years ago, I'm particularly heartened to see how far I have come.  So, without further delay, my most recent effort on M51 - The Whirlpool Galaxy.

M51 - The Whirlpool Galaxy.  11 x 5 minute light frames + approximately 25 flat frames and 30 dark frames for calibration.
Just to compare the difference, here's my attempt from back in August 2016.  It's a significant difference.

For comparison, my first attempt at M51 from August 2016
Time to wrap this post up.  Still to come over the next few days, I will look at the results of another couple of imaging sessions (although I haven't processed the data from those yet), a tour of the home observatory and the traditional blog post for Astrocamp, with a difference.
All the very best.  Stay safe!