You could see it previous nights' images so I had to select it for a target tonight.  Main emphasis here is on what appears to be a giant flame in the sky. Of course it is not alight. It is part of the Orion Giant Molecular Cloud region and is an emission nebula. Light from Alnitak is energising the atoms within and causing the electron to become exited. Most of the appearance actually comes when these electrons re-combine with molecular hydrogen. There is a big dust lane across the front.

I have doctored this picture a little by reducing the size of the bright star Alnitak. This is a common procedure in astro photographs where a subject would otherwise saturate the image. The smaller star is from a shorter duration frame that is patched in using graphical editing software.

Tonight I am going to be very ambitious.  I'm going to test it on the beloved Horsehead Nebula.  This is very close to the bright star Alnitak, in Orion's belt, and as we know such a star would soon saturate and test a refractors optics. Here is a single 10 minute self guided exposure with the Starlight MX7C single shot colour camera.

Here is the result of stacking 6 shots of 10 minutes each. The stars are nice and round (good tracking) and the colours are good too. Only problem is with shadows of (probably) dust motes on the lens. I can remove these by way of sky flats.  These are images of an evenly illuminated background, in my case I use the sky as it brightens in the morning!  However I wasn't aiming to stay up this late to obtain said flats.

Indeed I turned my attention to another object as the night was still young, only 2am.

Another small problem is showing up.  Hot pixels. Nearly every CCD camera has a few (or many) hot pixels that show up as one of the primary colours (red, blue or green).  Now I am getting a bit too clever for my boots as my tracking skills are improving.  Problem now is that a hot pixel will appear in each stub at the same place.  With accurate guiding the target is in the same place on each frame and hence so are the hot pixels.  Taking an average of many frames will not remove such hot pixels.  The technique is to use dithering.  This means the camera must be very slightly shifted between frames.  When the images are aligned on the target the hot pixels will be in a different place each time and will thus have little or no consequence on the final image when averaged.

So we see it is a continuous learning curve!

For the moon I have to reduce the iris in front of the objective lens otherwise it will be much too bright. This also changes the focal ratio from F12 to F22 which is good for a lunar/planetary object. Quite a surprise it has given the image is nice and sharp but it is tinted blue! Now in hindsight that is to be expected as the filter is designed to remove light pollution as well a moon glow!

For the rest of this evenings viewing click here:A-full-night-of-stargazing

Also on the agenda tonight is M45 or the Pleiades and also known as The Seven Sisters. As mentioned before this cluster is a good test of eyesight. Typically 5-7 stars can be seen by the average naked eye. There are in fact at least 500 stars in this cluster. The aim in photographing this cluster is to capture some of the nebulosity that still surrounds some of the stars as they awake from their cocoon. Again long exposure is required but this leads to saturation on the main stars. Here is my best attempt so far but still leaves a level or more to aim for.

M31 is very similar in structure to our galaxy in that both are large spirals. Indeed M31 had alway been considered much the larger of the twins but recent discoveries put our own galaxy possibly 50% lager then previously believed. Not so easy to measure from the inside. For this photo I am using the Canon Rebel/350 DSLR at prime focus. The Canon has a CLS filter that should remove skylight pollution especially from the street lights around my area. This seems to work but it tends to remove so much red that it leaves a blue hue as seen in this image. I was able to bring this more in-line with what I have in the past using a photo editing suite. Still this was an interesting effect which I will use again.

Now looking forward to darker skies.

Full Moon tonight and not much chance of any reasonable deepsky images. So let's turn a hand to capturing the Moon in it's full glory. The Full Moon can be somewhat difficult to image simply because it is too bright! As we are seeing it full on we are not able to appreciate the mountains, valleys and plains. Normally it is best to image when a thin crescent. At this time we can see the separator line, border between day and night, where mountains cast their shadows. It is interesting to note the Moon does not rise so high in the sky during summer. Although this would suggest better viewing of deepsky objects in summer it is countered by the fact we have fewer hours of darkness. Whereas in Winter with the longer hours of darkness the Moon rises so high it is almost daylight at Full Moon. Images of the Moon take a lot of tweaking and invariably always need improved contrast adjustments. This one is not so bad and is a composite of about a dozen images. The Software has a some difficulty auto aligning these and hence were manually aligned before stacking.

Getting a camera attached proved testing as even when the focuser is fully drawn it could not focus at infinity. Since I didn't have an extender I fitted a 6.3 Focal reducer instead. Here are some results.

Double star Albireo, also known as Beta Cygni, is a favourite for small telescopes and binoculars. To the naked eye it appears as a single star. Under moderate magnification one can identify the two component stars. These two stars are gravitationally bound and about 400 light years away.  

Here is the Globular cluster M13 which is also known as the The Great Cluster in Hercules. Probably the best known globular cluster in the Northern hemisphere.The colours are all wrong here and you can clearly see red/blue halos around some stars. This is an artifact (aberration actually) that plagues early design refractors. It is the result of red and blue light being focused at different points by a glass lens. More study needed here.

Opposite to Globular Cluster here is an Open Cluster.  This is not such a large one and might be hard to recognise as such. At first sight this looks quite a good image but again it is lacking the correct colours.

Overall a pleasing night of subjects and interesting information gleaned from the scope. It is a case of reading up alot on refractors to learn how to improve these images.

Clearskies

It is Boxing Day and a lovely clear night. Time to put a bit of colour into the Crab Nebula. This is probably one of my best shots to-date.

It has taken 32 x 1 minute shots to develop much detail.

Here is one of the firstlight photos.  It is a galaxy known as NGC891 and is seen edge on by us from our own Milky Way galaxy.   

In the meantime I've taken the camera out into the garden. Would you believe I have a banana plant in full bloom? It even has some thumb sized banana on it! This plant must be several years old now and well out of sync with it's native environment. My guess it had started to bloom towards the end of summer last year and I was not concious of it until this Spring! I wonder how long it will flower for?

Astrofest is an event I like to attend each year. However with the late night observing last night I am a little too sleepy to attend the lectures. I missed some very interesting ones this year, e.g. from famous comet hunter David Levy. They tend to be very well supported but the lecture room becomes very claustrophic. Indeed the supplier stands do as well. Hence I like to run around all the stands, several times actually, whilst eveybody is in the lecture Theatre. All the top UK Astro supplier are present and in particular Scope & Accessories as well as CCD imaging specialists. Nearly all offer a very big discount of 10% - 25% on their good for this event. So well worth saving up for this event.

In my Part I obtained just a couple of books. One on my Telecope and mount and the other on a calendar of observations for the current year. We shall read more about this as the year goes on. Of course both books discounted. I also purchased a green laser pen and mount for use alongside the finder scope on my telescope.