IC5146 the Cocoon nebula and environs

You learn fast that the month of June isn't particular good for astrophotography, the period of darkness is minimal and the DSLR gets warmer than norm, but at least I'm imaging in shorts and T shirt, and occasionally I have the company of a Pipestral bat.

Last night's sky was clear and I was eager to test run my reconfigured observatory. You see, since my last post and comment that everything was going hunky dory, my laptop threw a wobbly, the graphic/video card went belly up. It's fixed now though, thanks to an extended warranty. Phew, glad I got that.

A quick word on the observatory, I used to have 6 x 10 metre length cables twixt laptop and mount etc. I've now since put a powered USB hub next to the telescope, this has allowed me to remove 4 of those lengthy cables, and just run short ones from the hub. I should have done this earlier, but I didn't like the idea of 240 volts mains electricity on the terrace to power the hub, now though I've picked up a weatherproof electric box. It's working.

I always know well in advance what I want to image, I've been visualising this Cocoon nebula and the Barnard dark nebula B168 for sometime. I wanted to show the Cocoon nebula and its cometary like tail of dark nebula trailing behind, as if the Cocoon has pushed aside the stars. It remind me of the way a duck pushes aside the duckweed on a pond leaving a trail of clear dark water. (Right, less of my imagination)

I fitted the Tak with a 0.73 reducer which gave the telescope a focal length of 387 mm and an aperture of f3.6, the framing and composition is almost as I visualised it, it's just a gnat's smidgin out, which is causing an itch. It'll be round again for another go though.

The resultant photo is below, 12 lights frames and 10 flats, but no darks. I'm having problems with those for this image, they just added a terrible amount of noise. Also they looked a lot different to my other darks, work in progress.

Yes, I know it's upside down, I like it this way.



Constellation: Cygnus. Distance 3,900 light years.
Imaging scope - Takahashi FSQ-106ED f5 refractor fitted with Tak 0.73 reducer giving f3.6
Camera - Canon 40D
Filter - Astronomik CLS
Acquisition - Canon EOS Utility
Autoguiding - TMB 80 mm f6 refractor, Imaging Source DBK 21AF04.AS camera, EQ6 Pro mount and PHD guiding software.
Exposure - 12 x 300 seconds
Flats used.
Software - Nebulosity for focus, aligning and stacking. Photoshop CS3 with Noel's Actions and Russell Croman's Gradient Xterminator.

Barnard's E

These dark fingers of dust are collectively called Barnard's E, named after Edward Emerson Barnard who compiled a catalogue of dark nebulae. This pair are numbered B142 (on the right) and B143.

Of course one of the more famous dark nebula is Barnard 33 the Horse Head in Orion.

I became intrigued by these so called Barnard dark nebulae last year and took a pot shot at this one, managing to get just 1 x 300 second exposure, but at that time the nebulae were between a couple of trees, so, I wasn't able to follow up the project until this year.
Last night the sky was clear with just a slight high haze, isn't there always?

Imaging this was pretty uneventful, everything went alright and I managed 21 decent subexposures. Actually, for the past few months of imaging its been hunky dory, oh err, I've done it now.

So here it is Barnard's E, silhouetted against a rich background of countless stars. An uncropped version can be seen here.



Edit: Society for Popular Astronomy, Home page 15th June, 2009.
Picture of the week, British Astronomical Association, 29th June 2009.

Constellation: Aquila. Distance 2,000 light years.
Imaging scope - Takahashi FSQ-106ED f5 refractor at prime focus
Camera - Canon 40D
Filter - Astronomik CLS
Acquisition - Canon EOS Utility
Autoguiding - TMB 80 mm f6 refractor, Imaging Source DBK 21AF04.AS camera, EQ6 Pro mount and PHD guiding software.
Exposure - 21 x 300 seconds
Dark frames, Flats used.
Software - Nebulosity for focus, aligning and stacking. Photoshop CS3 with Noel's Actions and Russell Croman's Gradient Xterminator.

Temperature 12.5° C to 6° C

Messier 57, the Ring nebula

Planetary nebulae are some of the most colourful jewels of the night sky, this Ring nebula in Lyra was added to Charles Messier's catalogue in 1779. It's usually one of the first objects I show visitors as it never fails to please.

The sky started with a thin high haze which eventually cleared allowing me to keep 34 subs out the original 40 exposed, but shortly after I moved to my next target, the haze had returned with a vengeance, also the first light of dawn was just creeping up the horizon.

The first image is the full frame with just a few pixels nibbled off each edge to hide the dark alignment edges. I like wide shots like these, as it shows the nebula in its environment, the nebula is situated midway between Beta (Sheliak) and Gamma (Sulafat) Lyra. I would suggest that Sheliak is the bright star at the top and Sulafat that small quartet of stars at the bottom of the frame.

Click on the images for a enlarged view.



Hmm, it's niggling me now, I should have turned the camera 90° so those two stars had more breathing space. Note to self.

This second image is a closer crop to show the detail in the ring, within the ring is a 15th magnitude white dwarf star.



Constellation: Lyra. Distance 1,600 to 2,300 light years.
Imaging scope - Takahashi FSQ-106ED f5 refractor at prime focus
Camera - Canon 40D
Filter - Astronomik CLS
Acquisition - Canon EOS Utility
Autoguiding - TMB 80 mm f6 refractor, Imaging Source DBK 21AF04.AS camera, EQ6 Pro mount and PHD guiding software.
Exposure - 34 x 120 seconds
Dark frames, Flats used.
Software - Nebulosity for focus, aligning and stacking. Photoshop CS3 with Noel's Actions and Russell Croman's Gradient Xterminator.

Temperature 11° Celsius

Sunset

I suppose you wouldn't call this a true astro picture, but this sunset over Loch Ewe in Scotland is produced by our nearest and dearest star, the sun.



Canon 1D Mk2 with 16 to 35 mm lens mounted on a tripod. 1/5 second at f8, ISO 200.

Saturated coloured moon

Everybody appears to be doing it and I've done it myself in the past, saturating the colour of the moon.
Weather wise its been cloudy and I've been twiddling my thumbs waiting for clear skies, I decided to have another go at giving the moon a touch of colour.

I've used Photoshop and just added Hue/Saturation Layers, I've found it's better to use a number of layers and add a bit of saturation at a time, rather than whack a lot on at once. Before you start moving the sliders you need to align the RGB Channels, this can be done in Photoshop: Image> Adjustments > Auto Colour or you could do it manually.

Here's the result, the colour differences on the lunar surface may correspond to regions with differing mineral content. I suppose I could spend all day tweaking the sliders to suit and get a different outcome each time.



Further details on how to saturate the moon can be found on Filipe Alves's site here.

Have a look at these, Noel Carboni's on APOD or Russell Croman's here.

CLS Clipfilter

I've now fitted my Canon 40D with an Astronomik CLS clip filter, it's a light pollution filter. Up until now I've been using one that fits inside the T ring attachment of my telescope, which limited its use to the telescope.



The clip filter sits in front of the mirror and behind the lens throat, and allows me to use the filter with my camera lenses for those really wide shots I'm wanting to take. A secondary benefit is, it should keep dust out of the mirror box and off the sensor.

NB: It doesn't work with all lenses or cameras, so check if you are considering purchasing one.

The next step with this camera is to have it modified, but that'll wait until the warranty expires sometime in December.

Gibbous moon, 64 % of full

In the 20 minutes of clear sky I had last night I managed to snatch a photograph of the gibbous moon.



I've identified certain prominent features on the lunar surface in the photographs below. A couple of years ago I picked up a book for £5 in a second hand book shop, in Moffat, Dumfriesshire, Scotland. The book was called Amateur Astronomer's Photographic Lunar Atlas, by Henry Hatfield, published in 1968. So, I'm using his nomenclature, in fact, ever since I bought it, I always use it to identify features on the Lunar surface. Have things or names changed?



In this view can be seen a semi circle group of three mountain ranges, from the left, the Apennines, then Caucasus and on the right, the Alps. Look closely and you will see an alpine valley, cutting through the Alps mountain range.

Within the circle of mountains is the Mare Imbrium, the Sea of Showers.



This is the cratered southern highland area of the moon and craters of note here, are the three adjoining ones just above centre, Walter, Regiomontanus and Purbach. The three, right above centre are, Arzachel, Alphonsus and Ptolemaeus.

Takahashi FSQ-106ED with 1.6 x extender at f8 and Canon 40D DSLR, 1/60, ISO 100.