Monday, September 28, 2015

Super Blood Moon

  September 28, 2015    

It has been all over the news for the past day or so, but for those that missed it this morning was a rare opportunity to see a Super Blood Moon.  Whilst lunar eclipses are fairly common, the last total eclipse observed in the UK was in 2008 and the next will be in 2019.  However, what made this one particularly impressive was the fact it coincided with a Super Moon - the moon being at its minimum distance (perigee) to Earth, which means it appears 14% bigger and brighter.

My image of the Super Blood Moon
The name Blood Moon comes from the rust coloured appearance of the moon during totality, due to the small amount of light hitting the moons surface being filtered by the extremities of the earths atmosphere, removing the blue wavelengths and leaving a red coloured shadow on the moons surface.

Although totality was at 03:11 BST in the UK, the event started at 02:00, so it was an early start to make sure the telescope and camera were set up in time. I used the QHY8L CCD camera, attached to my Altair Wave 115ED refractor to ensure I had a good shot of the entire Moon's surface.  I started with exposures of just 0.001 seconds, but after totality I had to increase this to 25 seconds to capture the full detail of the surface.  I took 76 images to begin with, at 30 second intervals, which I processed using Time Lapse Assembler to create a short time lapse as the eclipse approached totality.  I then switched to single shots to get some detailed still images.


It might have been an early start, but it was an incredible sight and well worth the lack of sleep. If you missed it, don't worry - there will be another opportunity in 2033!

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Monday, April 06, 2015

The Leo Triplet

  April 06, 2015    

Work has been getting in the way recently so I haven't had much opportunity to get the telescope out, but the Easter holidays has meant I have been at home and the unusually good weather has given us astronomers a couple of relatively clear nights. Whilst the sky has not been completely clear, it was worth having a go at capturing some Deep Space Objects, although the near full moon rising just after 22:30 meant that I didn't have log before sky glow eliminated all but the brightest objects.

After a surprisingly quick setup, considering how many weeks it has been since I have had the scope out, I slewed to the M66 Group - otherwise known as The Leo Triplet. This group of three galaxies is about 35 million light-years away in the constellation Leo and consists of the spiral galaxies M65, M66, and NGC 3628.

The final image is the result of 8 x 300s exposures captured with a QHY8L camera attached to my Altair Wave 115 triplet refractor. The images were captured and stacked using Nebulosity 3 and processed using Photoshop CS6.

The Leo Triplet

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Friday, March 20, 2015

Catching The Eclipse

  March 20, 2015    

I missed out on the last opportunity to witness a solar eclipse in the UK, so I have been awaiting today's 98% partial eclipse with much anticipation. I had planned ahead and purchased my solar eclipse glasses well in advance, to avoid disappointment, so it was just typical that the British skies were overcast this morning. However, I was not going to give up so easily and so after a quick check of local weather forecasts, I jumped in the car with my family and we headed about 20 miles north of where we live in hope of clearer skies. It would seem luck was obviously with us today, because just before the peak of the eclipse at 09:25, the clouds started to break up and we caught a wonderful glimpse of the sun through a gap - a crescent slither of light in the sky. It was possible to get a couple of photographs between the clouds, but the heavy overcast sky somewhat reduced the overall effect of the eclipse - the sky did not darken as much as I had expected, for instance. However, these events don't happen very often in the UK, so I was pleased I was able to take my family to witness it live on this occasion.

Partial Solar Eclipse - 20 Mar 2015


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Sunday, February 22, 2015

The Rosette Nebula

  February 22, 2015    

With a clear sky forecast all night last night, I decided to have a go at imaging something new last. A quick look at Stellarium showed that the beautiful NGC2237 - otherwise known as The Rosette Nebula - was perfectly positioned in the sky. So, with my son to assist, I set-up the scope and had the target centred in my field of view within 20 minutes. After ensuring the focussing was okay I initiated a series of 14 x 900s exposures, using Nebulosity 3 to control the QHY8L CCD attached to my Altair Astro Wave 115 triplet refractor. I initially tried a medium 'dither' between shots - this basically moves the scope a little between each shot to try and minimise any backlash in the mount, but it took ages to settle down for the next exposure so I cancelled that and re-started without the 'dither' option selected.

With over 3 hours of data to collect, we retired inside to keep warm and left it running. Once the imaging run was complete I decided to have a go at capturing some 'Flats'. I have not used them before, but I have a few dust spots on my optics somewhere and I was given some good advice on Stargazerslounge last week about using Flat frames to get rid of them, so I thought I'd give it a go. I don't have a light panel, but my iPad screen with a sheet of paper in-front of it to defuse the light, seemed to work well enough.

When it came to processing the image the Flats and Darks made a good job of getting rid of a lot of artifices, although there were still some that needed removing manually. It was also at this stage that I realised that having stopped the session to turn of the 'dither' option, my focussing wasn't as spot on after I restarted. As a result, the Stars were not as sharp as I would have liked. I also have doubts about the field flattener - it is probably something to do with the spacing between flattener and CCD, which needs to be accurate down to a very small tolerance - more work required there I think. However, after a little processing in Photoshop, the final result is actually fairly reasonable I think.

The Rosette Nebula (NGC2237)
The Rosette Nebula (NGC2237) - 14 x 900s, Altair Wave 115 Triplet and QHY8L


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Tuesday, February 17, 2015

Catching the GRS!

  February 17, 2015    

Having fixed the rotation of Jupiter in Stellarium a couple of nights ago - see my previous posts - I noticed that there was a convenient Great Red Spot (GRS) transit this evening to test the software out, so I went out with the specific intention of checking that the prediction was accurate.

After slewing my Altair Wave 115 refractor to the rough position of Jupiter using Stellarium, I accurately aligned the system using AstroTortilla and there it was - I had Jupiter slap bang in the middle of my field of view. I then swapped my camera for the QHY IMG132E planetary camera and added the Tele Vue 2 x Powermate for extra magnification. After a little playing around with the focusing I could clearly see the GRS at meridian, meaning that Stellarium had accurately predicted the transit.

The image below is the result of the best 400 frames from an 87s AVI, stacked using AutoStakkert 2 and processed in RegiStax 6. Not a bad image for a 4.5" refractor! - click on the image to see a better quality version on flickr.

Jupiter, Io and Callisto - 17 Feb
Jupiter and the Great Red Spot, with 2 of Jupiter's moons - Io (bottom) and Callisto (top)

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Feeling Crabby!

  February 17, 2015    

Despite not feeling particularly well yesterday, the forecast of no moon and a clear sky all night provided an opportunity to test out my new Altair Wave 115 refractor on a deep sky object that could not be missed. So, as the sun dropped below the horizon I started moving my gear outside and setting up for an imaging session.  Once everything was setup and balanced correctly, I selected the Crab Nebula (M1) in Stellarium and slewed the scope to roughly the right location. I then used AstroTortilla to do a quick plate solving routine that established the accurate position of my scope and automatically re-centred on the right point in the sky - I love this software - so much easier than messing about with alignment stars.

Once it was dark enough to start a proper imaging run, I used Nebulosity 3 to instruct my QHY8L CCD to take 15 x 300s exposures, relying on PHD2 to accurately guide my scope through my Starlight XPress Lodestar camera and TS off-axis guider.  I then retired indoors for a nice warm drink, where I was able to monitor the progress via screen sharing on my iMac. Once the session had finished I went back outside and packed everything away.  I then went to bed - I wasn't feeling well after all.

The following morning, I reviewed the images and was pleased that only 1 image needed to be discarded.  I then used Nebulosity 3 to apply the dark callibration frames to the 14 remaining images before stacking. The result was a relatively noise free, although faint, image of the nebula, but most surprisingly, was the flatness of the image compared to those I got from my previous scope - the Sky-Watcher Explorer 190MN Pro.  With the exception of 1 corner, the stars seemed perfectly round across the image and there was no vignetting or background gradient at all.  Application of Neil Heacock's processing workflow, using Photoshop CS6 and Noel Carboni's Astronomy Tools resulted in a very nice looking image, with a stunning array of stars and a lovely structure to the filaments of the nebula. Overall, a pleasing result from my new scope.

The Crab Nebula (M1)
M1 The Crab Nebula - 16 Feb 2015



The Crab Nebula (M1) - Cropped
Cropped version of the same image, showing a closer view of the nebula

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Saturday, February 14, 2015

Fixing Jupiter's Rotation in Stellarium

  February 14, 2015    

I really like Stellarium, having recently started using it to control my scope through EQMod. It is great for scanning the night sky for suitable targets and even lets you zoom in to the planets to see the location of their moons.  What i didn't realise, until recently, is that the surface image of Jupiter showing the Great Red Spot (GRS) does not tie in with the real time rotation of the planet - how frustrating!  However, last night I discovered a work-around that allows you to adjust the rotation speed of the image in Stellarium to correspond with real time, meaning you can use this excellent planetarium software to predict the best time for observing GRS transits.

A Stellarium screenshot showing Jupiter, her moons and the Great Red Spot transit


Many thanks to Dion (of AstronomyShed fame) who provided the original instructions on the East Midlands Stargazers website http://www.eastmidlandsstargazers.org.uk/topic/198-grs-in-stellarium/ 
I have made a slight amendment based on my own system - Windows 7 Ultimate and Stellarium 0.13.1.

Firstly, download a program called 'notepad++' as this is far better for editing code. If you use the default text editor you just end up with a large block of code that is difficult to decipher. Notepad++ can be downloaded from here :-

http://notepad-plus-plus.org/

Once installed, you're going to just have a quick check of a website for transit times, so put in your correct time zone here :-

http://www.skyandtel...html?page=1&c=y

This will tell you when the red spot transits Jupiters meridian, ie, it's in the middle. So make a note of the times, all you need this for is to double check your edits have worked ok.

Next, go to the following location on your hard drive:

C:Users\<folder with computer name or your name>\AppData\Roaming\Stellarium\data

In the data folder you will have a file called ssystem.ini

Right click it and select "edit with notepad++"

Scroll down the list and you will see a section that looks like this :-

[jupiter]
name = Jupiter
parent = Sun
radius = 71492
oblateness = 0.064874
halo = true
color = 1.0,0.97,0.89
tex_map = jupiter.png #texture courtesy of Björn Jónsson
tex_halo = star16x16.png
coord_func = jupiter_special
lighting = true
albedo = 0.51
rot_periode = 9.927953
rot_rotation_offset = 105 #just some value good for GRS #old:151
#rot_obliquity = 2.222461
#rot_equator_ascending_node = -22.203
rot_pole_ra = 268.05
rot_pole_de = 64.49
orbit_visualization_period = 4331.87
atmosphere = 1

The part you want, is "rot_rotation_offset = 250".

Change the '250' to '65' and then at the top left in notepad++ click FILE and then SAVE. Close notepad++ and start stellarium.

**Please note that Dion successfully used the figure of 105, and other users have found different figures that worked for them, so a bit of trial and error may be required. However, I eventually came up with the figure of 65 that worked for me**

Advance the time in stellarium to a time when the above site says there should be a transit, zoom in on Jupiter in Stellarium and now the GRS should be placed around the middle.

All done

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Sunday, February 08, 2015

Jupiter and Europa

  February 08, 2015    

After a long run of bad weather I finally managed to get outside this evening and do a little imaging with my new scope - the Altair Astro Wave Series 115 ED F7 Triplet refractor.
After an initial alignment using Astrotortilla, I swapped the main camera for my QHY IMG132E planetary imaging camera together with a Tele Vue 2x Powermate and slew the scope to Jupiter. After focussing as best as I could I was quite impressed with how much detail I could see on my laptop screen and how little atmospheric distortion there was - a particularly rare still night. I then set about capturing several 89 second AVI files, averaging 20fps, which although significantly less than than the camera is capable of is about as much as my system will allow.
Once back inside (it was -2 outside) I set about processing the files. Firstly I stacked them using AutoStakkert 2 - taking the best 50% of the frames to make a single image. I then loaded it in RegiStax 6 and auto aligned and balanced the colour to get rid of a slight blue tinge on one side of the planet. I then adjusted the wavelets, which is a process that pulls out the finer detail in the planet's surface - I don't know how it works, but it does the job!
Jupiter and Europa - 8 Feb 15

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Monday, May 26, 2014

M13 The Great Globular Cluster - Lacking Colour

  May 26, 2014    

Sometimes things don't quite work out as expected. My latest image - M13 The Great Cluster in the constellation Hercules - is the first image I have taken for a while and the first taken using an Off Axis Guider instead of a guide scope. This should have been enough to warn against making too many changes, but I also decided to try out the latest version of Nebulosity 3. I used to use Nebulosity 3 as my camera control software with my Canon EOS, but when I upgraded to the QHY8L CCD it wasn't compatible so I started using EZCap - the software that comes bundled with QHY CCD cameras. However, the newest version of Nebulosity now supports the QHY8L so I thought I'd give it a go and I actually got on really well with it - until it came to processing. I'm not sure what went wrong, but my images seem to lack colour. There is a hint of it in there, but not enough to show the amazing blue and red stars in this beautiful cluster.

M13 - The Great Cluster

The image was captured using my QHY8L camera attached to a Sky-Watcher Explorer 190MN Pro, guided using an Off Axis Guider and Starlight Xpress Lodestar guide camera. It is the result of 10 x 180s images, captured and stacked in Nebulosity 3 and processed in Photoshop CS6. I believe that Nebulosity may have automatically debayered the image prior to saving it to disk - obviously the settings must have been wrong. Whilst it is a lovely image, showing lots of detail in the cluster, I can't wait to try again. Next time I will do a sample run with Nebulosity to see if I can get it working, otherwise I will have to revert to EZCap.

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Saturday, May 24, 2014

Tuesday, November 12, 2013

M42 Orion Nebula - First Light With The QHY8L

  November 12, 2013    

After what seemed like a long wait, I finally had a clear night this week and managed to get first light with the QHY8L that I purchased second hand on astrobuysell.com. The target was M42 (the Orion Nebula) and I have to say that I am quite pleased with the result. The image was captured using the QHY8L camera, cooled to -20 degrees, and attached to a Sky-Watcher Explorer 190MN Pro. The image consists of 10 x 200s and 10 x 45s exposures, captured using the QHY EZCAP software, with initial processing and stacking in Nebulosity 3 and final processing in Photoshop CS6. Equipment used is the Sky-Watcher Explorer 190MN Pro, mounted on a NEQ6 with a 2" Hutech IDAS LPS P2 filter to enhance contrast and reduce the effect of light pollution.

The Orion Nebula (M42)
M42 Orion Nebula

The shorter exposures were important so that the Trapezium (tight group of 4 bright stars in the core) did not become blown out. However, the longer exposures are important to capture the finer detail of the nebulosity. 

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