Chasing the ISS with a Canon SX20IS

The International Space Station passed over my house this evening, about to dock with the STS-133 Discovery space shuttle. Though I wasn’t able to see the shuttle (I understand from tweets that it was very close), the ISS pass was pretty bright and lasted for a good few minutes. Fast moving cloud spoilt the first image where the ISS approached from the SSE. However the following three images I hope you’ll agree aren’t too bad despite the weather doing its best to spoil the view.

ISS Pass 1

Here the ISS (the long line, a 32 second exposure), left hand part of the line is passing over Betelgeuse and Bellatrix in Orion. Aldeberan can be seen up to the right and faintly, the Pleiades can be seen.

ISS Pass 2

In this second inage the ISS has passed Orion (whose distinctive outline can be seen on the right of the image) and is approaching Castor and Pollux in Gemini to the upper left.

ISS Pass 3

This final image shoes the ISS track partially obscured by cloud, just before it disappears from view.

I used my Canon SX20IS mounted on a Jessops photographic tripod, taken at ISO100, using CHDK to set a 32 second exposure, at f7.1. I used a two second delay to allow the camera shake to settle down before the shutter engaged. The images have had a small amount of post-processing applied to brighten the scenes slightly.


Website Update

Just a quick update as to what is going on, as there hasn’t been a posting to my blog for a (unbelieveably) couple of months. I’m working on a substantial update to my website which will consist of a number of tutorials, based on what I have learnt in astronomy and astrophotography.

Watch this this space for announcements before the end of the year…!

Posted by Wordmobi

Astrophotography with the Canon SX20 Part 2

As mentioned in my previous post, now I’m back off holiday I’ve compiled my photos from the SX20 and as per the images below, are some of the results.

Below is a cropped shot of the region around Cassiopeia, the full image (see link – 4000 x 3000 res) also shows (if you look hard enough) M31 in the lower right hand side of the image.

Link to full size image:-

SX20 Cassiopeia / M31

Image Details: ISO800, f4, 15 second exposure.

The next shot shows the Andromeda Galaxy (Messier 31) at about 10x optical zoom:-

Full size image link:-

SX20 Messier 31

… noticeable at this level of zoom, even though the camera settings haven’t changed, are the star trails. Image details:- ISO1600, f5, 15 second exposure.

Overall, even though there is a level of noise in the SX20’s images, it is substantially better than the S2IS’s, which is very pleasing to see.

Astrophotography with the Canon SX20IS Part 1

I’m writing this blog entry whilst still on holiday and not having any means of transferring my digicam pics to my smartphone, so I’ll present the text first and images later.

A holiday to the Scottish Highlands presented itself with an opportunity to take advantage of (potentially) clear dark skies as I usually have to put up with light-polluted skies at home.

I hadn’t really tried out my new Canon SX20IS digicam for some astrophotography, preferring to continue to use my ageing S2IS with CHDK. However the SX20IS really offered a number of advantages over the S2IS such as better ISO capabilities (ISO 800 to 3200) and better resolution. So over a couple of nights, whilst dodging some broken cloud, I managed to obtain some impressive (in my eyes and with my limited photographic ability) images that kicked the S2’s images on the first night into a cocked hat.

As a comparison, on the first night I mainly used the S2IS with CHDK and took a number of exposures 20-32sec in length, ISO400. A lot of noise was picked up and only the brightest stars were picked up. However I was able to save these as RAW images so I may be able to obtain more detail once I get back to my laptop. I took a couple of disappointing shots with the SX20 which only picked up the very brightest stars in Cassiopeia.

However the next night I decided to use the SX20 and after making some aperture changes and setting the ISO value to 1600, this really opened up the quality of the images. Once the broken cloud had nearly completely cleared, I set the camera up on a wooden table on top of the tripod (there were trees all around so I couldn’t get any horizon shots) and started snapping again and Cassiopeia. With the ISO set to 1600, aperture F2.8, manual focus and time 15″, the images taken had substantially less noise than from the S2IS and more stars were picked up by the SX20’s CCD.

As I took more shots and applied the zoom slightly to M31 (Andromeda Galaxy) which I managed to pick up in the image, the aperture adjusted automatically to F4.0. However because I couldn’t see M31 in the viewfinder, it was hit-and-miss (more miss actually) aand couldn’t get a closer image of the object. Even though ISO has more image noise, I’ve been very impressed with the SX20’s ability to take low light shots – and I haven’t even tried the ISO3200 mode yet!

Posted by Wordmobi

Moon and Mars Opposition

The 29th and 30th of January was the closest approach of Mars since 2007 and the ‘largest’ Moon of 2010. Thankfully the skies in the UK were clear (well, where I live at least!) and gave good opportunity for some observing and astrophotography.

Though my first target was Mars, because the telescope was still ‘warm’ from only just being brought out from the house, this created poor ‘seeing’ from the small air turbulences inside the telescope as it cooled down. This created a shimmering blob effect that when coupled with 2 and 5mm lens, ruined the image.

Whilst I waited for the equipment to cool down, I decided on a bigger target that would be affected less by the aclimatisation problems. So I turned to the Moon and grabbed my Canon S2IS digital camera, holding it upto the eyepiece. Because I’d already worked out some test shots with aperture and shutter speed in CHDK, I applied the settings and managed to get the whole of the Moons disc in the eyepiece. One of the shots is pictured below, though I haven’t had chance to correct the rotation of the image so that the Moon looks the right way up. I had my Moon filter attached to the eyepiece and the only post-processing applied was auto-levels in Photoshop.


By this time the scope had cooled down sufficiently to view Mars. Even though I’d fitted various combinations of barlow lens, 5 and 2mm lenses, I couldn’t manage to quite get much surface detail imaged, except two horizontal curved bands, one of which I guess corresponds to the polar cap. There was a hint of red-orange colour around the edges of the sphere, I didn’t bother trying to try imaging it with my hand-held afocal coupling method of taking pictures with the camera, as I felt it it would result in a blurred image.

Instead, I fixed the camera to the mount on the telescope and took a shot of the Moon and Mars (which was directly overhead), displayed below:-


The image has been rotated and cropped due to the angle that the camera was viewing the scene. A small amount of red’ blue, brightness and contrast has been applied to the image.

Final shot for this post is the equipment setup:-


Mars is at closest approach to Earth for the whole of this week, before receeding until 2012.

Posted by Wordmobi

New Years Partial Lunar Eclipse

Thanks to some of the information gained from reading my new digital imaging Astronomy books, I’ve managed to capture a few shots of the moon, in partial lunar eclipse on new years eve, the best of which is:-

(Click the image for a slightly larger version).

The image was took with my Canon S2IS running CHDK, attached to a mini tripod sat on the roof of my car. This the best of three shots, I didn’t get any more time to take any more as I was supposed to be getting ready for new years party! It was took at time of greatest partial totally, approx 19.22 UTC.

I also managed to get some shots around 1am of Orion in the western sky. Unfortunately they turned out to be overexposed so much that the sky was a light grey colour. The stars created a trail because I left the shutter open far too long (40 seconds). However, I still think this was a result as I caught the Orion Nebula on the image, something I never manged to achieve. I think I’ll need to shorten the exposure time by half to eliminate the star trails and exposure brightness.

Throwing these images into Registax resulted in all sorts of alignment errors, due to the rotation of the earth. Time to read some tutorials how to align stacked images I think!

Christmas for the Beginner Amateur Astronomer

Well, Christmas has been and gone and what has Santa brought good little astronomers? Whatever you’ve wished for, I hope you’ve got what you wanted and your enthusiasm continues to rise for astronomy.

I’ve been very lucky and after a little searching around the internet and visits to bookshops, I’ve compiled my list of ‘Got It’ (this Christmas) / ‘To Get’ of material helping me towards getting to grips with digital astrophotography and astronomy in general.

Here I will give a short overview of the books I’ve been lucky enough to receive and some bits to get.

‘Got It’
1. Introduction to Digital Astrophotography (Book, Willmann-Bell Inc.) Link here
I’ve been looking for a book that emcompasses general digital photography techniques allied with practical application in astronomy. I personally have a tendancy to look for a book that is like a ‘magic bullet’ that not only covers the subject material I want, but also in a style that immediately appeals to me. For several months I have been trying to track down something that matched my requirements, with no luck. At one point I even searched ‘’s’ entire list of astronomy books and came up with nothing! A search via Google bought up the Willmann-Bell website and I browsed their list of books, including this one. What attracted me to the book was the available index list in a PDF, which included basic photography techniques and practical astrophotography.

The book was available to order from the US online and after calculating the shipping to the UK, it worked out at about $72. The book arrived around 10 days later, very well packed and my wife promptly hid the box, keeping it for Christmas!

So, far I’ve been very pleased and impressed with the book, there is so much information contained in the book it will keep me going for months if not years. The writers style, though the book is packed full of information, presents in a very easy, clear manner and this has helped me to dive straight into the book and start to apply some of the techniques immediately.

2. DK Digital Photographers Handbook.
A more general photography book, picked up cheaply from an exhibition, I picked this up for its more general photography information and advice. First impressions are good, I’ll add more information on the book shortly.

3. Practical Astronomy (Book, Philips)
The Philips series of Astronomy books are an excellent reference for beginner and the more advanced amateur astronomer. I’ve already got the ‘Stargazing with a Telescope’ and the ‘Stargazer’ pack and found them very useful.
The Philips astronomy books can be found at: link here . Lots of pointers for beginners and the basics are well covered.

‘To Get’
1. Canon CA-PS700 Mains Adapter.
For those long exposure shots of the night sky…

2. Some form of afocal digital camera adapter for my Skywatcher Explorer 130PM telescope.

3. A new set of rechargable batteries as my six-year old spare set of 1500mAH NiMH’s have fianally given up.

Thats it for the moment, I’ll report on how the reference material helps out…

Posted by Wordmobi