Categories
Deep Sky Nebula

Gyulbudagian’s variable nebula

I got an email to say that Gyulbudagian’s nebula was brightening again so grabbed ten 3 minute exposures just before dawn on Monday. Taking advantage of the 7 hour time difference between the UK and New Mexico made this a much more reasonable 11am.

While it’s possible to distinguish the nebula as a small fan shape this is still a very faint object. The brightest star in this image is Magnitude 10.1 and some of the faintest, 19.4

The telescope used was GRAS-1, a Takahashi Mewlon 300mm with FLI IMG1024 Dream Machine camera. I’ve written before about this camera with it’s 24 micron pixels. It’s very sensitive, but this system suffers from pronounced vignetting which isn’t entirely compensated for by the flat frames when the images are stretched as much as this one.

Categories
Deep Sky Open Cluster Solar System

Kelling Heath Star Party – (Pt 1)

Got back from my first Spring star party on Sunday afternoon having arrived Friday evening. The event was wonderfully cloud free with a lack of aircraft contrails as well; something to do with a volcano in Iceland!

While the skies were clear there was more sky glow than I remember from the autumn event. On the first night there was a lot of moisture in the air with dew dripping off every surface pretty much from nightfall but on the second  this didn’t start being a problem until after 2am, by which time I was thinking about bed.

On Friday I had problems getting the AstroTrac to track at all well but this had resolved itself by Saturday and I concentrated on Mars in M44 and M13 in Hercules. 24x 2 minute exposures at ISO400 through the ZenithStar 70.

M13 to follow.

 

Categories
Deep Sky Galaxy

The Leo Quadruplet

While the Leo Triplet is well known, there is a fourth member of this group a little further away and it’s depicted here in this 2.5 degree field.

All three galaxies in the main triplet show signs of interaction and the group as a whole is listed in Arp’s Atlas of Peculiar galaxies as ARP 317. M66 is also listed separately as ARP 16 (Spiral with detached segments). Distance to the group is about 33 million light years and measuring this picture shows that the nuclei of M65 & M66 could be as close together as 192,000 light years. By comparison, our nearest galactic neighbour is M31, Andromeda at 2.5 million light years. Leo

The image is a stack of 15x 3 minute exposures at ISO400 using the WO Zenithstar  70 with a Sky Watcher field flattener.  Some trailing is apparent and the individual frames could use rather more exposure time and/or a higher ISO setting.

 

 

Categories
Deep Sky Open Cluster

The Double Cluster revisited

This being a Bank holiday weekend, and the skies being cloudy I’ve had some time to review the DVD presentations from the 2009 Mid West Astro Imaging Conference that I bought from Astro Photo Insight some time ago. Two were of particular interest; “The Hows and Why of Image Calibration” by Kevin Nelson of QSI and “Choosing a camera for astrophotography” by Craig Stark. After watching these I decided to evaluate some flats produced by pointing the telescope with Canon 350D at a blank illuminated laptop screen (I used an empty Notepad window). Analysing these images in Maxim, the results were nothing like I expected; less an even grey frame, more a technicolour nightmare!

 

 

After that shock I went back to look at my images of the Double cluster and reprocessed them with the new flat frames. Compared to my original efforts there’s much more colour evident in the stars and the overall blueish tint is much reduced. How much of the improvement is down to the flat frames and how much to improved technique is up for debate.  That’s all part of the fun; there’s always something new to learn!

 

 

Categories
Deep Sky Open Cluster

Caldwell 94

Having bought the book ‘The Caldwell Objects – and how to observe them’ it’s only fitting that I identify this object with it’s Caldwell number rather than the rather nondescript NGC 4755. Located in Crux, The Southern Cross, at a declination of -60 degrees this is a Southern Skies cluster only.

Also known as The Jewel Box this compact cluster is just 10? in size and could be mistaken for a 4th magnitude star with the naked eye. 5,000 light years away , the stars in it are about 15 million years old.

This image is comprised of 28 3 minute LRGB exposures (12,6,6,4).

 

Categories
Deep Sky Galaxy

Siamese Twins

There’s been rather a trend on this blog towards pairs recently and to continue this theme here’s an image of NGC 4567 & NGC 4568, sometimes known as the Siamese Twins. This pair of interacting galaxies are part of the Virgo cluster and for some years were considered a line of sight pairing as there’s no visual evidence of interaction.

This image is the result of a stack of 14 five minute frames taken on GRAS-4 over two nights.

Categories
Deep Sky Galaxy

M81 & M82

This picture was taken with the Canon 75-300 zoom before I bought the Williams Optics refractor. The focal length is 190mm and this image is about one quarter of the original field. Sixteen 3 minute exposures were combined and despite the short exposure time and mis-shapen stars some detail is visible in the galaxies. Also in the frame are two more smaller galaxies, NGC 2976 is on the right and NGC 3077 is at the bottom.

 

Categories
Deep Sky Open Cluster

Double Cluster

After I noticed the stars were trailing on the images of M51, I rechecked the polar scope picture when I’d re-positioned for the Double Cluster in Perseus. It required a small tweak in azimuth and I then took 10 3 minute exposures at ISO 400 that were combined in Maxim. The trailing was eliminated and although there was some coma apparent in the corners of the image I removed some of this by cropping the picture. Looks like a field flattener will be required.

Categories
Deep Sky Galaxy

New telescope

p>Whilst spending the weekend with my Dad, we stopped off at Astronomia in Dorking, Surrey. There on the shelf was a Williams Optics 70mm Zenithstar. I’ve been looking for something small and light to replace the Canon zoom lenses on the AstroTrac and this fitted the bill exactly. Having parted with some money, I took it home and contrary to known astronomical principles, the following night was clear!

First target, M51. This being a first attempt I wasn’t too sure what to expect at the longer focal length and the tracking wasn’t perfect so I finished the run with just 5 images of 3 minutes each. With the Canon 350D attached, the 420mm focal length yields 3.14″/pixel.

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Categories
Solar System

Saturn

Saturn is back in the evening sky. Having shot some three colour video sequences of Mars on the Celestron 9.25 I switched to Saturn which was just rising out of the murk at about 20 degrees elevation. The rings are just beginning to open out after last year’s edge on aspect and with the planet higher in the sky as it approaches opposition it should be favourable for imaging.

1500 frames each of red, green and blue video were stacked and combined for this image.