Noctilove astrophotography barn door tracker » Page 3 of 7 » Astrophotography with the ultimate barn door tracker DIY build guide

Auriga

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!

To 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 D7000, Nikkor 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.

A colourful conjunction

Comet 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 D7000, Nikkor 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.

Despite 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 D7000, Nikkor 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.

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 D7000, Nikkor 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.

Comet Lovejoy – C/2014 Q2

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 D7000, Nikkor 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.

The Pleiades

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 D7000, Nikkor 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.

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.

Twistleton Scars

The Summer Triangle rises above Twistleton Scars in the Yorkshire Dales. The Milky Way bisects the scene with the great Andromeda galaxy visible in the top left of shot.

Omega nebula & Eagle nebula

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.

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..

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 D7000, Nikkor 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.

Comet Jacques – C/2014 E2

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 D7000, Nikkor 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

Another 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 D7000, Nikkor 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.