Archive for the ‘Astrophotography’ Category

Astro Pixel Processor – Learning about LRGB processing

March 30, 2020 Leave a comment

I have been used to imaging in the past with RGB colour cameras, but now that the iTelescope remote telescope network has switched completely to cameras fitted with the more sensitive mono sensors and RGB filters I am forced to learn a new method of processing to combine RGB exposures with the luminance exposures. This is a good skill to learn as the images will potentially be more detailed with less noise and this is how the vast majority of astro imaging is done.

I saw the recommendation for the Astro Pixel Processor software on the iTelescope website and it seems to be well respected with good results so I thought I would give it a go on the free trial offer. Astro Pixel Processor can be found here There is an excellent video tutorial taking you through all steps to process an LRGB image of the Small Magellanic Cloud NGC292 here LRGB Tutorial The data was kindly made available by Christian Sasse,

The tutorial is in 9 parts and easy to follow although some of the menu items have changed in the latest update to those visible in the tutorial and there are additional options when loading files that are different too like the panel asking you about which session you want to use. I just went with the defaults and dropped all files into Session 1 every time and everything worked out fine.


The staged workflow is easy to follow and the software is actually very good at auto processing many of the early stages with minimal input. The fun really starts in the Tools section after you have combined the RGB image following calibration, registration and integration. Here you can calibrate star colours, remove light pollution and crop the image to suit. Then you can switch to the Preview section on the right and follow through the comprehensive Digital Development Process (DDP) including adjustment of the black/white point, saturation, sharpness, contrast, select the correct histogram stretch and much more. The changes are visible in real-time on the screen and when you get to a result you are happy with just save the stretched image as a Tiff or Jpeg.

I was pretty pleased with the results for a first ever process of LRGB data and look forward to using the software for comet and supernova imagery.


Small Magellanic Cloud processed in Astro Pixel Processor using data by Christian Sasse. Star Spikes added with Starspikes Pro in Photoshop Elements.

The Dark Skies of Anglesey, North Wales

March 11, 2016 Leave a comment

Spent a few days up on Anglesey near Penmon where they have stunning dark skies so I took the opportunity to do a little astrophotography from the back garden of the cottage, which overlooked the sea to the north. Orion was prominent in the western sky while to the south Jupiter was rising above the roof and through the trees. Many star clusters were visible with the naked eye including the Double Cluster, three clusters in the southern half of Auriga and M44 (The Beehive) near Gemini. The Andromeda Galaxy was easy to find in the north.

The Isle of Anglesey AONB is currently working towards gaining Dark Sky Reserve Status and you can follow their progress here The view was quite spectacular on a moonless night with stars from horizon to horizon. Light pollution was minimal for naked eye viewing, particularly to the north and west. The main problem for photographers will be the large number of passenger jets heading east – west in the north and it was difficult to take a photo which did not have a plane trail in it.

All images taken with the Sony RX100, F1.8, 28mm, ISO 3200, 8 second exposures.


Orion in the west


Jupiter rising through the lower branches of the tree


Jupiter gleaming over Penmaenmawr and the Snowdonia Mountains


Looking west to Benllech and Amlwch with the constellations Cassiopeia, Perseus  and Andromeda. The faint smudge just right of centre is the Andromeda Galaxy.


Looking north west to Cassiopeia and Andromeda with the Milky Way faintly glowing


The Plough looking north east

Probably the most amazing astronomy book you will buy this year !

February 18, 2014 Leave a comment


I’m talking about This Is Mars by Alfred S. McEwen, Francis Rocard and Xavier Barral with contributions by Sebastien Girard, Nathalie Chapuis and Nicolas Mangold and published by Aperture.

OK, first thing to note, it’s not cheap ! At £65 this may stretch people, but fortunately you can find it as low as £39.25 now using Amazon marketplace sellers. Second thing to note, it’s huge ! Measuring 30 cm wide and 36 cm tall this will not fit on most standard bookshelves and will almost by default become a coffee table book. You are, however, buying quality here. This hard bound book is beautifully designed and executed and falls somewhere between art and science in content.

The photographs of the surface of Mars presented here are both beautiful and utterly astounding and derive from the HiRISE camera mounted on the Mars Reconnaissance Orbiter, which has been taking ultra high resolution images of Mars since 2006.  The 150 black and white images are just short of A3 size and presented on very high quality art paper with each image covering an area 6km in breadth.  The range of landforms is staggering, from plunging canyons, vast black dune fields, towering volcanoes, craters, glacier flows and swirling trails left by desert twisters to name but a few.

After a brief introduction by the editor, Xavier Barral, about two thirds of the book is taken up with photos while the final third includes a series of short papers. The first is a description of the HiRISE camera and MRO project by Alfred S. McEwen. This is followed by an excellent essay by astrophysicist Francis Rocard covering the evolution of Mars and it’s geology (together with some detailed maps) which includes a timeline of the main observations of Mars from the 2nd century AD through to 2012. Finally, there’s a geomorphological tour of the surface of the Red Planet by Nicolas Mangold using the photographs in the book, which explains the origins of the numerous features you will see in the photographs.

I cannot recommend this book highly enough and I doubt anyone interested in astronomy would be even remotely disappointed to receive this book.

More information at the publisher’s website here




M101 Supernova 2011fe and Comet C/2009 P1Garradd 4-9-11

September 5, 2011 Leave a comment

So last nights attempt to capture remote images of the supernova in M101 and Comet C/2009 P1 Garradd proved completely abortive! GRAS in New Mexico was completely clouded out all night and so was Spain until early morning. Having stayed up until 3.30am to make sure I caught M101 before it got too low in the sky I figured I would switch to the Spanish telescopes where Stellarium was telling me that M101 was visible around 4am. This proved to be incorrect due to a glitch with the timezone settings in Stellarium and the telescopes could not find the object – so I had nothing to show for a sleepless night !

Tonight was an altogether different scenario. I double checked where I had gone wrong with Stellarium and corrected the error. It showed I had a narrow window of opportunity between 8.00 and 8.45pm where I could image M101 before it dipped below the critical 40 degrees in azimuth where the telescopes in Spain cannot image due to the height of the surrounding walls in the observatory. The observatory went live around 8.15 pm so I logged onto the GRAS 7 telescope which is a Planewave 17″ imaging with an FLI ProLine PL11002M camera and set up for 15 mins of Luminance, bin 1, in 300 and 600 second exposures. At the same time I logged onto GRAS 16 and imaged C/2009 P1 for 10 minutes using the Takahashi TOA 150mm refractor and SBIG STL11000M camera. The moon was up at the time, but I was imaging away from the main area of moonglow (GRAS recommend imaging objects at least 60 degrees away from the moon) so I guessed everything would be OK – and it was !

Considering these images are just 10 minutes exposure I was pretty blown away by the results !! There’s a nice tail extension on the comet and the supernova is clearly visible in M101 as a 10.5 magnitude (now 9.9 September 6th ! ) exploding star which is now easily rivalling the galactic core in brightness. I’m used to processing Jpeg and Tiff files from the DSLR for astro images so the FITS files that you download from the GRAS server were a bit of a mystery to me. I downloaded the FITS liberator software and read the manual then got stuck in with the initial processing and saved the results as Tiff files. I was totally amazed at the quality of the images when I opened them up in photoshop for a bit more tweaking – nice clean images with hardly any signal noise. OK so i’m now officially hooked on remote telescope imaging 🙂

Anyway – here are tonights images greatly reduced in size (and quality) from the Tiff originals

M101 Pinwheel Galaxy and Supernova 2011fe which is marked by the arrow

Comet C/2009 P1 Garradd

GRAS – Global Rent A Scope – First Light

September 3, 2011 Leave a comment

It does feel like cheating at first. You should really be out there in the elements connecting everything up amidst a rats nest of wires and cables, balancing the equipment, aligning the mount, locating your objects to image, focussing, imaging, transferring the files, calibrating and processing – or at least you would be if there wasn’t wall to wall cloud, which is what I have had over the last two weeks. I’ve been going slightly crazy looking at all the great images of comet C/2009 P1 Garradd appearing in numerous photogenic pairings as it passes by famous deep sky objects. And then there’s Supernova 2011fe in M101 which has been slowly brightening to its maximum current magnitude of 10.5, rivalling the galactic core for brightness in images. While a few notable images have rolled in from staunch amateurs and their home observatories many people have been using remote telescopes to capture their own visual keepsake of these unique astronomical events.

You soon get over the guilt of going fully remote of course, particularly when you realise that this is how professional astronomers grab their images anyway, just with much bigger telescopes and more sophisticated imaging devices. And even the amateurs are not really roughing it these days. Most of the top imagers have fully automated observatories and merely have to set the imaging targets on a computer and the kit does the rest while they go back to sleep. So don’t feel guilty, just get those images taken any way you can and revel in the fact that full remote automation is even available to the amateur these days.

Many of the remote images I have seen originated from GRAS or Global Rent A Scope which has an array of telescopes available in three locations including New Mexico (US), Spain and Australia. So I figured I would initially try the system out on the Free Test Drive offer using GRAS 003 in New Mexico which is a Takahashi TOA 150 refractor (1100mm/ f7.33) paired with an SBIG ST2000 XCM 2 megapixel one-shot color camera. The Test Drive deal gives you 60 points to use which basically gives you about an hour on this setup with the ability to capture 3-4 ten minute (600 second) exposure images. The registration was painless with just basic details collected, then you are sent an activation. After activation an email arrives by return with your unique username and password. You then wait 15-20  minutes for your account to go live on the GRAS servers. When your account goes live you sign in to the GRAS Info Centre where the first thing to do is check if the observatory you are using is in the night portion of the colour day/night animation. Also check if the all sky camera for the observatory shows a clear sky with obvious stars. I then clicked on the G3 telescope when the ‘Available’ message appeared in the constantly refreshing list of telescopes.

The GRAS Info. Center with me on the G3 telescope……

On the Free Test Drive your options are pretty limited once you get to the actual telescope control screen. You can only choose to image a set number of famous objects (all of them Messier objects when I was using the system) from a short list using the One Click Image system. They will all be objects at least 45 degrees above the horizon and if you choose something below that level you will get a message telling you the object is unavailable. To my dismay M101 was out of range at the time (11.20 pm US time) and comet C/2009 P1 wasn’t even listed, so I was left with a fairly mundane list of familiar Messiers.

As the camera is one-shot colour providing a fully RGB calibrated image I decided to target some colourful objects and picked the M27 and M57 planetary nebulas. The exposures are locked at 10 minutes (600 seconds) so you just click on the Submit button next to the image of the object you want to target and off the telescope goes. A scrolling script screen provides detailed feedback on the whole process and after about 12-15 minutes you get the message that the session is complete. The server then automatically calibrates and processes your image for you and sends it as a jpeg file attachment in an email.

The initial single jpeg images you will receive by email are poor quality heavily compressed jpegs weighing in at just 80kb in size and 800×600 pixels. These are just the preview images however and you should shortly receive the zipped FITS files by email or you can download them from the GRAS server using an appropriate FTP client (I use the GRAS recommended FTP Surfer which is free). For a 10 minute exposure the results are quite surprising ! After converting the calibrated FITS file to SBIG RGB in Maxim DL5 and stretching the levels I did a  bit of gentle noise reduction, increased the contrast in the nebula slightly and increased the star colour using Noel Carboni’s Astro Tools plugin in photoshop. There was M27 in glorious (and fairly accurate) colour with plenty of detail in its structure and a nicely dense starfield around it  – I was feeling quite chuffed 🙂  M57 was a bit lost in the widefield image and stared at me like some brightly coloured Saronesque eye, but even that image looked decent after a bit of tidying.

M27 – The Dumbbell Nebula – 10 minutes, one shot colour – processed image

M57 The Ring Nebula – 10 minutes, one shot colour

At this point cloud rolled in and the New Mexico observatories all closed their doors for a few hours. I headed back to GRAS at around 4am US time and most of the telescopes were back online. Wanting to try a different scope I went for the G20 which is a Takahashi FSQ-ED 106mm 530mm / f5 widefield refractor paired with an FLI ML8300-C  8.3 megapixel one-shot colour camera. At this point I should have done my research as I chose M76 The Little Dumbbell nebula to image. This is really too small an object and too distant for these widefield scopes and looks hopelessly lost in a very pretty starfield – lesson learned !

M76 Little Dumbbell Nebula – hugely cropped !

Having now set up Stellarium (version 0.11.0) for the various observatory locations I have researched the correct times to catch M101 and C/2009 P1 more than 45 edgrees above the horizon in New Mexico. I also put the various telescope and camera combinations into CCD Calc 1.5 so that I could see what the field of view for M101 would be (C/2009 P1 FOV confirmed from other peoples images) and GRAS 03 seems to be the telescope for the job.  OK , i’m all ready for another session on GRAS 03 around 3am tomorrow morning UK time, weather permitting in the US. I’ll post up the results tomorrow – wish me luck !

EDIT 4/9/11 – Quick update – it was cloudy all night at the New Mexico location and the domes remained closed – so no images taken !

Categories: Astrophotography

Sunnymeade Astro appears on the Imaging Source Blog

September 6, 2008 Leave a comment

It was a pleasant surprise to find that Jonathan Maron of IS had picked up my ‘First Light’ report on the DMK 41AU02.AS from 23/8/08 and included it on the Imaging Source Blog along with the images – thanks for the kind comments Jonathan!

Categories: Astrophotography, Solar

The Sun 23-8-08 – First light for the DMK41AU02 Camera

August 23, 2008 Leave a comment

The DMK 41AU02 USB camera arrived yesterday. At 1280×960 resolution this should theoretically be able to display the whole disk in IC Capture and allow single videos of the surface and proms to be taken which can be combined without having to laboriously stitch panes together. First light today proved that this is indeed the case. It was great being able to see the whole disk on the screen. Until I zoomed out I was scrolling a lot to see which edge was passing out of frame view first, but zooming out made this easy to judge so that the disk could be centred on the chip for best overall focus.

Having found the optimum settings for prom and surface capture I saved these configurations specifically for the DMK41 as the DMK21 configurations cannot be used and result in an error. A video of 2000 frames produces a file size of 2.28 GB in just over two minutes at the 1/15 sec max capture rate. In Registax 4 I came up against the problem that Registax will only recognise AVI files up to 1GB in size which equals 869 frames. Beyond that Registax throws up a read failure message and the aligning procedure fails. So until registax 5 comes out I may be limited to videos of 869 frames, which isn’t too bad, but I would prefer to be able to stack at least 1000 to reduce noise in the final image. K3CCD Tools may be the answer to my problem but an early attempt to stack in that resulted in confusion – I need to read the manual !

The whole disk view does seem to show up the shortcomings of the PST now though. It appears my PST may be slightly astigmatic with focus better on one half of the sun than the other. This is really obvious now whereas with the smaller DMK21 each pane was capable of being sharpened so that the overall view looked more consistent. Sharpening the whole DMK shots does look OK though and the inconsistent focus may even be due to the chip not being square to the objective in the holder – need to check that!

Today was not exactly the sunny, blue-sky day that was promised by the weather forecasters! We actually got 1 hour of patchy clear sky then thick cloud the rest of the day and rain in the evening. I captured these images at 9.16 UT. Not much to see in terms of proms, but the active region is a little larger and there were some small filaments around. Overall i’m pleased with the speed at which I can create a high resolution full disk now and will be even happier when Registax 5 comes along !

Categories: Astrophotography, Solar

H-Alpha Art!

March 27, 2008 1 comment

I got back from work too late to catch the sunspots yesterday, but I managed to take a few images of the sun as it was setting behind a hill almost a mile away. The effect of the silhouetted trees in front of the sun is quite dramatic and although the sunspots and filaments on the sun are not very clear the whole image is really quite pleasing. The branches of the trees have an almost frosted look to them in stark contrast to the glowing furnace behind them. Here’s the image……..

Categories: Astrophotography, Solar