Standing on the Shoulders of Giants

Standing on the shoulders of giants - Orion rises over Helvellyn in the English Lake DistrictOrion rises over the jagged slopes of Helvellyn in the Lake District. The figure standing in silhouette on England’s third highest mountain is dwarfed by the constellation.

Taken from the lower slopes of Striding Edge, a friend wilfully volunteered to stand on the edge of a precipice as a setting crescent moon illuminates the distant snow-capped peaks.

Using the barn door tracker at half speed allowed me to effectively double the exposure time before the motion blur of either the ground and the sky became noticeable.

This technique combined with the altitude and the dark skies of Cumbria helped bring out the classic deep sky objects. The Great Orion nebula, Horesehead nebula and Flame nebula all make an appearance. With a hint of Barnard’s loop just visible.

The really comes into it’s own with this type of wide angle constellation shot. Making the reddish gold of Betelgeuse and the brilliant white of Rigel stand out spectacularly in the scene.

Image details: Nikon D7000Nikkor 35mm f1.8G at f2.8. 30 seconds at iso 1600 using didymium filter and softon filter. Tracked at half speed with barn door tracker.

[ad]

Pacman nebula

pacman nebula in cassiopeia DSLRThe Pacman nebula is named after the classic 80’s arcade game character, but to me it looks much more like an angler fish! The little nebula (officially named NGC 281) sits alongside the bright yellow star Scheder, inside the familiar W constellation of Cassiopeia.

A surprising amount of detail is captured in the 66 minute exposure taken at 180mm. Using the softon filter to enhance the string of bright nearby stars forms an attractive triangle with the nebula…

pacman nebulaImage details: Nikon D7000Nikkor 180mm f2.8 at f2.8. 66 minutes (132 x 30 seconds) at iso 1600 using didymium filter, plus 3 minutes (6 x 30 seconds) at iso 1600 using . Stacked with Deep Sky Stacker and tracked with home made barn door tracker.

[ad]

Bonus autumn aurora…

[divider]

For reasons not fully understood, you’re around twice as likely to see an aurora in spring or autumn then in summer or winter. Even a mild solar flare or gust of solar wind from a coronal hole can spark off a display. This was a great example as it took me completely by surprise a couple of nights before taking the pacman nebula shots. I did managed to get a tantalising glimpse of the display through the clouds thanks to some timely twitter notifications..

aurora animationImage details: Nikon D7000Nikkor 50mm f1.8 D at f2.8. 10 second exposures at iso 1600. Animated in Photoshop.

[ad]

Comet Lovejoy, Owl Cluster & Dolphin Nebula

Comet Lovejoy and the Owl ClusterComet Lovejoy continues to shine as it journeys through the Solar System. Early last week the comet passed the Owl Cluster in Cassiopeia, making for another great photo opportunity.

With one of Cassiopeia’s brightest stars ‘Ruchbah‘ (right of shot) guiding the way, comet Lovejoy is an easy target to find at the moment. It’s surprising to see how bright the tail still is, with plenty of structure still visible. (Click the image for a larger version).

Just below Lovejoy sits the brilliantly named Owl Cluster, with the two brightest stars forming the eyes. The small nebula just above the comet is the little known Dolphin nebula, a small planetary nebula around 850 light years distance. The cluster of stars at the top right of the image is Messier 103.

Image details: Nikon D7000Nikkor 180mm f2.8 at f2.8. 16 minutes (32 x 30 seconds) at iso 800 using didymium filter, plus 2 minutes (4 x 30 seconds) at iso 800 using . Stacked with Deep Sky Stacker and tracked with barn door tracker.

[ad]

Flaming Star nebula

flaming star nebulaAfter giving up on it a couple of weeks ago, I decided to have another try at the Flaming Star nebula, this time under better conditions…

Heading a few miles out of town to darker skies makes a huge difference for such a faint subject. The darker background not only make the nebula more visible, but also allows for longer exposure times before light pollution levels get too high. Because of this I was able to double the normal length of sub exposure to 1 minute, taking fifty in total.

To highlight the stars, a couple of extra minutes exposure using the was enough to bring out the colours in the line of stars beside the nebula.

Even with the extra light gathered, the final image stacked with Deep Sky Stacker took plenty of work in Photoshop to reveal the reds in the Flaming Star nebula and glowing cluster NGC 893 sitting opposite. Also revealed in the middle of the shot is the jewel-like Spider Nebula (IC 417) along with its prey, the tiny Fly Nebula (NGC 1931) seen just to the left. The two open clusters in the shot are M38 (top left) and M36 below.

Doubling or tripling the 50 minute exposure time would be necessary to improve the quality of the image. It looks a little grainy due to all the post-processing. But with the time I spent on processing, I think I’ll leave it at that!

Image details: Nikon D7000Nikkor 180mm f2.8 at f2.8. 50 minutes (50 x 60 seconds) at iso 800 using didymium filter, plus 2 minutes (4 x 30 seconds) at iso 800 using . Stacked with Deep Sky Stacker and tracked with barn door tracker.

The wide angle shot below, taken at 35mm a few weeks ago, puts the 180mm shot in context…

Auriga wied field taken at 35mm

[ad]

Auriga

Auriga with nikon 35mm f1.8 G lens

Imaging full constellations is something I’ve been itching to do since trying the new softon filter. So last night I set off in search of some darker skies armed with a borrowed Nikon 35mm f/1.8G lens. The constellation of Auriga was the target as it’s perfectly placed overhead at this time of year, and imaging large targets overhead is much preferred. (Trying to remove gradients from targets lower down is a real nightmare).

With an exposure time of 22 minutes, the detail visible in the shot is pretty impressive. The centre of Auriga holds two open clusters, M36 and M38, which sit beside a couple of faint nebulae; the Flaming Star nebula, and the less catchy IC410 – an area which could be an excellent target for the 180mm lens at some point.

The lens itself worked like a charm. Stopped own to f4 it’s super sharp, and the light weight makes it easy on the barn door tracker (200g vs 800g for the 180mm). I also had a pleasant surprise when it came to stacking the images as I realised I’d also caught the California nebula in the upper right of the shot!

Hoya Softon A filter for astro  imagingTo get the glowing star effect I took nine 2 minute photos without the filter, then two shots with the softon filter in place. I stacked these separately in DSS and combined them in Photoshop with the softon layer set to ‘screen’.

This side-by-side caparison of 2 minute shots of Capella demonstrates the filters effect. The medium to bright stars stand out much more, as well as their colours. The filter also dims the background stars making the constellations pop out even more.

Image details: Nikon D7000Nikkor 35mm f1.8G at f4. 18 minutes (9 x 2 minutes) at iso 800 using didymium filter, plus 4 minutes (2 x 2 minutes) at iso 800 using softon filter. Stacked with Deep Sky Stacker and Photoshop. Tracked with barn door tracker.

[ad]

A colourful conjunction

Comet lovejoy and the pleiadesComet Lovejoy continues to impress as it swiftly passes through the winter sky. A conjunction with the Pleiades and Hyades star clusters in Taurus set up a beautiful wide-angle photo opportunity last night for which I was lucky enough to have clear skies. The intensely green comet, the electric blue Pleiades and the vibrant orange of Aldebaran formed a colourful celestial triangle.

This is the first image I’ve taken using the excellent new softon filter which really makes the brighter stars in the constellations pop out, as well as emphasising their true colours. It should be especially good for wide-angle shots as a way of making the constellations more recognisable. As with all the filters I use, I bought the largest size possible, then simply use step-up rings to fit them to any of the lenses.

Image details: Nikon D7000Nikkor 50mm f1.8 at f4. 8 minutes (8 x 60 seconds) at iso 1600. Using didymium filter and softon filter. Stacked with Deep Sky Stacker and tracked with barn door tracker.

Comet Lovejoy imaged with Nikon D7000 at 180mm f2.8Despite painfully cold fingers, I persevered with the hand-driven barn door tracker to capture a few closer shots with the 180mm lens. The comet has certainly evolved over the few days since the last shoot.

Image details: Nikon D7000Nikkor 180mm f2.8 at f2.8. 5 minutes (5 x 60 seconds) at iso 1600. Using didymium filter. Stacked with Deep Sky Stacker and tracked with barn door tracker.

Comet Lovejoy stacked in DSS Using Deep Sky Stacker’s comet mode lets you fix the comet’s motion, revealing more detail in the structure of the tail.

Image details: Nikon D7000Nikkor 180mm f2.8 at f2.8. 10 minutes (10 x 60 seconds) at iso 800. Using didymium filter. Stacked with Deep Sky Stacker and tracked with barn door tracker.

[ad]