An Island in a Sea of Stars


This image looks toward the inner spiral arm of our Milky Way called the Norma Arm, where stars bunch together to form the rich Norma Starcloud, a prominent patch in the southern Milky Way. What you see here is all stars, lots and lots of stars.

Seemingly embedded in the sea of stars is an island of brighter stars called the Norma star cluster, or more prosaically NGC 6067. It’s about 6800 light years away, much closer to us than the more distant stars behind it. It is literally floating in front of the background sea of stars.

As with the previous image, this is a wide field shot, taken with the 135mm telephoto, to frame the field much as it would appear in binoculars. This shot is a stack of six 2-minute unguided exposures at ISO 1250 with the Canon 7D riding on the little Kenko tracking platform. It’s one of a couple of dozen fields I shot the first night of shooting on Chile in May.

— Alan, June 4, 2011 / Image © 2011 Alan Dyer

 

 

 

 

Rose of the Southern Sky


It’s been a month since my last post, a month with no new astrophotos from home. But I’ve got a backlog of RAW files to work through from the Chile trip a month ago. Here’s a new image from that shooting expedition. It’s of an area of the southern sky that lends itself to every focal length and framing variation — you can’t go wrong with the Carina Nebula!

This wonderful nebula in the deep-south Milky Way rewards any astrophotographer. For this shot I used a 135mm telephoto (Canon’s wonderful f/2 L-series lens) and the Canon 7D camera. The 7D is what I call a “stock” camera, used just as it comes off the dealer shelf. The 7D does a superb job capturing the red nebulosity and its faint outlying bits and pieces. It tends to record these clouds of glowing hydrogen as magenta in tone. By comparison, my other Canon camera is a “filter-modified” 5D MkII. You can see a shot of this same area of sky taken with the 5D MkII a few blogs back under The Best Nebula in the Sky, posted May 6. The 5D MkII’s modification (which replaces the filter in front of the sensor with a new astro-friendly one) allows it to record deep-red wavelengths and picks up more faint nebulosity, registering it more as red in tone. But both images look good and presentable.

This field is rich in objects — not only the main sprawling nebula but nearby star clusters and patches of dark dust clouds. It is one of the finest fields in the sky for binoculars, and this shot approximates the field of view of typical binos. I like to shoot a lot of objects with telephoto lenses — while the main subject is not frame-filling and in your face, it does match (at least in field of view) what you can see in binos, useful for illustrations and observing articles. Of course, the camera picks up  more stuff and colours even your bino-aided eyes can’t see.

This shot is a stack of five 2-minute exposures at f/2.8 with the 135mm telephoto, on the Canon 7D at ISO 1250. I used the little Kenko Sky Memo tracking platform for this, letting it track without any added guiding. It’s tracking was spot on, with nary any star trailing as it followed the target for 20 minutes or so.

— Alan, June 3, 2011 / Image © 2011 Alan Dyer

Under the Southern Cross


I’m back home in Canada now, after 24 hours of travel from Chile. Despite having to check my carry-on bag filled with cameras and the Mac laptop for the Calama to Santiago domestic flight, all the gear arrived home intact. Now to process the 40+ gigs of images I shot. And properly reprocess some of the images worked on at the dining room table at the lodge, under the bright Chilean sun.

Here’s a shot taken the last night of shooting, of the icon of the southern sky, the Southern Cross, more formally called the constellation of Crux. Next to it, at left, are the dark clouds of the Coal Sack. To the eye, these clouds looks like a uniform dark spot in the sky. But photos, and even binoculars, reveal it as a complex mess of shapes and densities.

What stands out are the colours of the Cross stars. Most are hot blue Type B stars – energetic blue giants. But Gacrux at top is very red – it’s a cool red giant star.

Scattered amid the Cross are Coal Sack are several clumps of stars – open star clusters, such as the Jewel Box Cluster to the left and just below Becrux, the left star of the Cross. On our final night at the Atacama Lodge, we helped out at the lodge in a public stargazing session to a group of tourists from all over the world. I ran a telescope aimed at the Jewel Box and heard lots of ooohs and aaahs at the sight of its multicoloured stars.

This shot is a Mean-combine stack of five 3-minute exposures at f/2.8 with the wonderful Canon L-series 135mm telephoto, and the Canon 5D MkII camera, filter-modified, at ISO 800. The camera was on a Kenko SkyMemo tracking platform, which followed the stars during the 15 minutes worth of exposures.

– Alan, May 9, 2011 / Image © 2011 Alan Dyer

The Galactic Cathedral


We’re on our last full day in Chile, packing up and sorting out. I’ll finish off my Chile blog series with this parting shot — the entire southern Milky Way from horizon to horizon.

In this view, we’re looking straight up, with the horizon at the edges of the frame of the 15mm fish-eye lens. The glowing starclouds of Sagittarius and Scorpius, seen in close up in the previous blog post, are in the centre of the frame. The Southern Cross is at far right, the Northern Cross at far left.

This scene is a superb way to end a night of southern sky stargazing – just lying back and looking up at the entire panorama of the Galaxy. You really do get the sense that we are indeed living at the edge of the Galaxy, looking off into its bright core, and with its spiral arms wrapping around us.

It’s a galactic cathedral of stars.

– Alan, May 7, 2011 / Image  © 2011 Alan Dyer

The Starfields of Sagittarius and Scorpius


I can’t get enough of this region of sky. I can and do shoot this with every lens I have and with all kinds of framing (horizontally, vertically, or at a rakish angle, like here) and it always looks great.

These are the rich and stunning starfields toward the centre of the Milky Way in Sagittarius (bottom) and Scorpius (at top). Look for the pinkish nebulas dotted along the Milky Way, the bright starclouds, and the dark lanes of interstellar dust. It’s all part of the galactic recycling program that our Milky Way participates in, as stars explode, cast off dust and gas, which then clump into glowing nebulas and form new generations of stars.

I took this shot about 5 a.m. a couple of mornings ago, with this area directly overhead. It’s a stack of six 3-minute exposures with the 35mm lens and Canon 5D MkII camera. I took some shots through a soft focus filter to add the star glows.

– Alan, May 7, 2011 / Image © 2011 Alan Dyer

The Best Nebula in the Sky


What a great field this is to explore with binoculars. The image here takes in about the same area of sky as most binoculars and look what it contains! Arguably, the best nebula in the sky: the Carina Nebula, and the best open star cluster: the Football Cluster (aka NGC 3532) to the left of the main nebula. And then there’s the Southern Pleiades star cluster, IC 2602, below the nebula, and lots more besides.

This one field is reason enough to travel to the southern hemisphere for stargazing.

I shot this last night, May 6, 2011, using a 135mm telephoto lens at the modified Canon 5D MkII camera. The filter modification allows the camera to pick up a lot more of the faint wispy bits of glowing nebulosity. This is a stack of four 3-minute exposures, with two of the exposures shot through some thin cloud (the first we saw all week!), adding the subtle but photogenic glows around the stars.

– Alan, May 7, 2011 / Image © 2011 Alan Dyer

Belt of Venus and Volcanoes


This was the scene we were treated to each evening at the Atacama Lodge in Chile. Quite an amazing skyline, with 5,900-metre-high Licancabur Volcano, here at sunset.

The sky colour comes from a phenomenon known as the Belt of Venus, a magenta/pinkish glow from sunlight lighting up the upper atmosphere after the Sun has set for us on the ground. The dark blue rimming the horizon is the rising shadow of the Earth.

I have punched up the colour saturation here to bring out the colours, but not so much as to be faked — the colours are real!

This is a shot with the 50mm lens and Canon 7D camera, taken on one of the nights we had dinner back at the lodge, in this case with a group of Québec amateur astronomers also here this week who were great observing friends on the field.

– Alan, May 7, 2011 / Image © 2011 Alan Dyer