Orion nebula revisited

Orion Nebula with barndoor trackerThe plan was to capture the flaming star nebula in Auriga last night, with it being overhead. I set the tracker up, took a few shots and immediately realised just how faint it was!.. As an antidote to this disappointment, I aimed the camera at the brightest nebula in the sky, the Great Orion Nebula.

I was able to add another 60 shots to the 112 I already had from last years efforts. I had reworked the 56 minute image several times, improving the results each time as my post processing techniques have developed.

The sequence below shows a progression from single 30 second photo, up to the latest image of 1 hour 26 minutes. There’s a big jump in image quality at each stage, with the latest image being much sharper due to the improved barn door tracker design. I also managed to find a more pleasing colour balance compared to the slightly muddied earlier versions.

Orion Nebula image processing sequenceImage details: Nikon D7000Nikkor 180mm f2.8 at f2.8. 1 hour 26 minutes (172 x 30 seconds) at iso 800. Using didymium filter. Stacked with Deep Sky Stacker and tracked with barn door tracker.

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Evolution of comet Lovejoy

Despite being chilled to the bone on more than one occasion, tracking comet Lovejoy over the past month has been a great experience. It was, and still is, a stunning comet. Shooting Lovejoy on a total of 10 occasions over the last month with varying levels of success, I’ve stitched together the best of the bunch to show how the comet has evolved over time…

Nikon 180mm f2.8 D810aFor the earlier shoots I experimented with different exposure lengths (15-60 seconds), different ISO levels (800-1600), different lenses and different focal lengths (50mm, 85mm and 180mm). This was probably not the best tactic as the best results came from a 12 mile trip to darker skies on the 24th, using the tried and tested settings of 30 second exposures at iso 800 with the 180mm/f.2.8 lens. The image quality is visibly better in this shot mainly because the comet was near zenith so less post-processing was needed to remove the effects of light pollution…

Comet Lovejoy 2015 star trackerImage details: Nikon D7000Nikkor 180mm f2.8 at f2.8. 5 minutes (10 x 30 seconds) at iso 800. Using didymium filter. Stacked with Deep Sky Stacker and tracked with barn door tracker.

Comet Lovejoy with blue tailAs Lovejoy recedes further from Earth, its movement through the sky also appears slower. So although it’s starting to fade, it allows for many more exposures before the movement becomes an issue with the stacking. For example this 14 minute exposure from the 6th February vs. the 4 minute exposure on the 13th January.

In the recent images from early February you can clearly see the huge dust tail curving as the comet passes around the Sun.

Image details: Nikon D7000Nikkor 180mm f2.8 at f2.8. 14 minutes (28 x 30 seconds) at iso 800. Using didymium filter. Stacked with Deep Sky Stacker and tracked with barn door tracker.

I’ll no doubt take more shots of Lovejoy, but as can be seen in the most recent image from the 10th of February, the tail seems significantly dimmer now. Whether this is just another fluctuation in the structure of the tail, or a more significant decline, we’ll have to wait and see.

So I’m left with a series of shots showing comet Lovejoy’s evolution, along with a very full hard drive!.. Let’s hope the next comet Terry Lovejoy discovers is as good as this one.

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Samyang 85mm f1.4 lens..

astrophotography with Samyang Rokinon 85mm f1.4On a side note, the Samyang 85mm f1.4 lens I bought specifically for the job of imaging the comet proved to be no match for the trusty Nikkor 180mm f2.8. Unlike the results with comet Jacques, the tactic of maximum light gathering didn’t pay off this time. The lens may prove to be better suited to other subjects, but I’m not convinced as the coma was very noticeable even when stopped down. I think the ultra sharp Nikkor 85mm f1.8 G is the way forward at this focal length.

Image details: Nikon D7000Samyang/Rokinon 85mm f1.4 at f2.8. 4 minutes (16 x 15 seconds) at iso 800. Using didymium filter. Stacked with Deep Sky Stacker and tracked with barn door tracker

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Comet Lovejoy update 17th February…

Comet Lovejoy 2015 passes the Little Dumbell NebulaWith the skies finally clear after a week of cloud, I jumped at the chance to capture another shot of Lovejoy as it passed by the Little Dumbbell Nebula (M76). The planetary nebula is so tiny and faint that it’s considered one of the trickiest objects in the Messier catalogue to observe. The comet itself is definitely fading now, with the tail in particular much harder to pick up.

Image details: Nikon D7000Nikkor 180mm f2.8 at f2.8. 12 minutes (24 x 30 seconds) at iso 800. Using didymium filter. Stacked with Deep Sky Stacker and tracked with barn door tracker.

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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.

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Comet Lovejoy – C/2014 Q2

180mm f2.8 Nikon D7000 barn door tracker
Ever since hearing about newly discovered comet Lovejoy C/2014 Q2 in the Autumn of last year, I’ve been eagerly anticipating its arrival. Even splashing out on a new lens for the occasion. Unfortunately the weather has scuppered any plans I had to capture the comet in early January, with endless amounts of cloud, usually rolling up just as it gets dark!..

Last night, however, a fleeting break in the clouds allowed me to grab a handful of shots as the comet makes its way past Earth and on towards a close encounter with the Sun on the 30th of January.

I didn’t anticipate much detail with just 8 images to go on (4 minutes total exposure time), but at least the the stacking process was a quick one. The final image above reveals a surprising amount of structural detail in the tail, along with its stunning blue colour. The comet appears much larger than I expected too, the tail now stretches over 10 degrees (20 times the size of the full moon), with much of this huge tail cropped off the bottom of the frame.

With comet Lovejoy quickly moving higher into the northern hemisphere sky, and with the tail changing structure on a daily basis, it should still be a great target for the next couple of months – weather permitting!

Image details: Nikon D7000Nikkor 180mm f2.8 at f2.8. 4 minutes (8 x 30 seconds) at iso 800. Using didymium filter. Stacked with Deep Sky Stacker and tracked with barn door tracker.
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The Pleiades

The Pleiades star tracker

The open cluster of the Pleiades is a captivating sight in the winter sky, with nebulosity visible even to the the naked eye. Longer exposures reveal the electric colour of the blue hot stars at the cluster’s heart. These bright stars make it tricky to capture the fainter wisps of nebulosity without causing excessive coma. Stopping the lens down to f4 (instead of the usual f2.8) helped a lot with this, but resulted in some diffraction spikes, which I actually think work nicely.

Image details: Nikon D7000Nikkor 180mm f2.8 at f4. 36 minutes (27 x 80 seconds) at iso 1600. Using didymium filter. Stacked with Deep Sky Stacker and tracked with barn door tracker.

Pleiades-UGC2838 Just beside the Pleiades, next to the perfectly named Electra, lies one of the most distant galaxies I’ve yet managed to capture. Looking like a mere smudge in the image, edge-on galaxy UGC 2838, at 300 million light years distance, is an incredible 676 thousand times further away than the Pleiades themselves. At magnitude 17.88, it is also by far the faintest object I’ve knowingly photographed.

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Omega nebula & Eagle nebula

Eagle nebula and Omega nebula wide angle

The Omega nebula, also known as the Swan nebula (although it looks more like a snail to me) in Sagittarius is a tricky one from this latitude (54° north) as once the summer twilight passes and it’s dark enough to take photos again, it barely gets above the horizon. I had a good go at capturing it though, despite massive light pollution which kept the exposures down to just 15 seconds.

M17 omega nebula wide

Just above the Omega nebula lies the Eagle nebula (I was able to fit them both in the same shot). A 36 minute stack of 144 shots was enough to bring out some detail, including my favourite, the ‘Pillars of Creation’ in the centre of the nebula.. You’ll need to look closely..

eagle nebula wide shot with nikon d7000

I think revealing these features is really pushing the limits of what can be achieved with the 180mm lens and barn door tracker. The tracker is more than capable of handling higher magnifications though, so to get better shots with finer detail, I would need to invest in a bigger lens.

Details: Nikon D7000Nikkor 180mm f2.8 at f2.8. 36 minutes (144 x 15 seconds) at iso 1600. Using didymium filter. Stacked with Deep Sky Stacker and tracked with barn door tracker.

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Comet Jacques – C/2014 E2

comet Jacques 2014 passing the heart and soul nebula
Comet Jacques is now perfectly placed for Northern hemisphere observers. Visible all night for the next month or so, it’s path takes it directly along the spine of the Milky Way. This should make for some interesting conjunctions, and some good photo ops in the coming weeks, as it slowly fades away.

Although Jacques has turned out to be a lot dimmer than predicted (with an especially faint tail), I still wanted to capture the comet’s flyby of the famous double cluster in Perseus.

I’ve had mixed results with comets in the past, so this time I decided on a tactic of maximum light gathering. This involved stepping down from the usual 180mm f2.8 lens and instead using the 50mm f1.8 lens for maximum aperture. The lens produces a lot of coma around the stars when shot wide open, but as the comet is so faint and diffuse, it isn’t actually affected by it. The 50mm focal length also allows for longer exposures than the regular 180mm lens due to the larger margin for error. The comet’s movement through the sky also becomes much less of an issue.

Taking a series of 3 minute exposures, I was pretty happy with the composition. What I hadn’t realised at the time was that I’d captured something else in the frame. It wasn’t until I began to process the images that the nebulae appeared. Amazingly, the comet sits right between the Heart and Soul nebulae, which I had no idea existed beforehand. These two very faint nebulae should make a great target with the 180mm lens later in the year when they move overhead.

Details: Nikon D7000Nikkor 50mm f1.8 at f1.8. 18 minutes (6 x 3 minutes) at iso 800. Using didymium filter. Stacked with Deep Sky Stacker and tracked with barn door tracker.

Comet Jacques update: August 21st

Comet Jacques 2014 taken at 180mm with barn door trackerComet Jacques 2014 stacked to cometAnother clear night allowed me to shoot the comet Jacques for a second night in succession. But this time with the 180mm lens.

The comet had moved further than I thought in just 24 hours, now sitting right beside the brightest part of the Heart nebula. It’s exactly this speed of movement which makes shooting comets so tricky. The 18 minute image above (stacked on the stars) captures the nebula well. But the comet, and especially the tail, is blurred by the movement.

The second image (stacked on the comet) freezes the motion to finally reveal the thin, wispy tail in a bit of detail.

Details: Nikon D7000Nikkor 180mm f2.8 at f2.8. 18 minutes (36 x 30 seconds) at iso 1600. Using didymium filter. Stacked with Deep Sky Stacker and tracked with barn door tracker.

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