Double Exposure


Double Exposure

The artistry and artisanship of astrophotography

It begins in the imagination.

Like any good photography, astrophotography starts with vision. What is the shot you would like to take? What elements would it include? How will they be arranged? What’s the final look of the shot going to be? The shot that we are going to unpack in this eBook started life as a conceptual idea I had. In my mind, I could see exactly what I wanted the outcome to be, even before I went anywhere near the location.

But, more so than regular landscape photography, the technical challenges of shooting in low light mean that you can’t simply jump in the car, turn up at the right place at the right time, press click and realise your vision. All aspects of photography benefit from good technical skills and understanding. But astrophotography especially does so.

So, in this eBook, my goal is to unpack both those elements.

  • The artistry - how you can previsualise your shots

  • The artisanship - how you can use your camera to bring your vision to life.

The vision of the artist

I have come to love this constellation very much this year. Since first photographing it over Belfast’s Cavehill in the snow in January, I’ve been keen to find places to photograph it that provide a real Northern Irish context to it. On my online meanderings one day, I saw someone who had photographed it with a little stream in the foreground. The way the water fell over the rocks created lovely white water in long exposures and I thought it made for a strong image.

But where in Northern Ireland offered somewhere where I could have a go at a shot like this? I wanted a decent amount of water flow, preferably a drop in the water for the long exposures. It had to face south to south-west so that I could get Orion in it. Was there anywhere like this?

Then it struck me: Dunseverick. It had the waterfall there, so the water drop was ticked off. And there was a headland of rock that protruded out past it so that I could turn back south for Orion.

In my head, there was the constellation sitting above the waterfall in the sky, with the fall of the white water set in stark relief against the dark greys of the basalt rock, with white water in the ocean in the foreground. All I needed was the right conditions: clear skies.

But this, of course, is Northern Ireland. So a few weeks went by, with Orion moving more and more out of position. Would I get a chance to grab this shot before the season was out?

Eventually, there was a clear night forecast, and I headed to the coast, straight for the waterfall.

Conditions were perfect. There was Orion, just above the waterfall as I had hoped, with glorious clear skies meaning the Hunter was so very visible, even against the blanket of other stars vying for attention.

I got set, pressed the shutter button, and a few seconds later, this shot appeared on my camera screen.

The technique of the artisan

Except, of course, it didn’t! So, what of the technical settings that allowed me to produce this shot?

Your big challenge in astrophotography is getting enough light to fall onto your sensor. There are two ways you can do this: one is to have a wide aperture lens (such as f2.8 or wider); the other is to leave your shutter open longer.

Think of it this way. Imagine you are trying to collect rain falling from the sky into a jar. If you have a huge funnel you can put in the top of it, you can collect more drops of rain. If you hold your jar out for a longer period of time, you’ll collect more rain. Wider and longer equals more collected.

According this this theory, you can just leave your shutter open for five minutes and boom - job is done!

But it’s not that simple, for two reasons.

  • Due to the spin of the Earth, if you leave your shutter open that long, the stars will begin to trail. And, instead of having those wonderful spots of light, you’ll have lines. Not exactly what our vision was now, was it?

  • If you keep your shutter open that long, you are likely to blow out the highlights of the stars, losing those lovely colours that the stars and nebula of Orion bring.

So, keep the exposure shorter then. For a 16mm shot like this one (on a Fuji camera with a 1.5 crop factor) I can go for 30 seconds before getting star trails (Google the 500 rule for more information on how to calculate your maximum exposure time). But, when I do that, I end up with a foreground that’s far too dark and underexposed.

Here’s our dilemma: expose for the stars and the foreground will be too dark. Expose for the ground, and the stars will trail and have blown highlights.

Double exposure

The solution is simple: take two exposures, one for the stars and one for the ground. And that’s exactly what I did here. This technique is a very powerful one for allowing you to get well balanced night time shots. I've included the two jpgs straight out of camera so you can see what I was working with (although, I was shooting in RAW, of course, to give me greatest flexibility in post production).

The first shot (below left) is the shot for the sky and I set the camera to the following settings:

  • ISO 6400

  • f/2.8

  • 30 second exposure

As you can see, the stars are acceptably sharp and the sky is well exposed. You can make out the foreground, but if I were to pull out any of the shadows in Lightroom, it would quickly become very noisy.

Here’s the second shot (below right) for the foreground, with the following settings:

  • ISO 400

  • f/2.8

  • 600 second exposure

The foreground here still looks quite dark, but as I was shooting at ISO 400 instead of ISO 6400, I knew I could pull out the shadows whilst controlling noise much better. You’ll also notice just how much star trailing there is in this exposure time (although the lower ISO actually allowed me to retain colour in the stars).

Post production

Image 1: the ground

The first step was to battle the light pollution. A sodium street lamp to my left was spilling in a lot of orange light onto the scene - and that’s even with me shooting with a White Balance of 3200 Kelvin!

The first job then was to make some global adjustments in Camera Raw to do two things:

  • Reduce the oranges in the foreground (by making localised adjustments to White Balance)

  • Reduce the overall saturation of the foreground.

This ended up with me being able to use the sodium light as a pleasant side light to the image, rather than this horrible orange glow.

I boosted the shadows in Camera Raw too, and used a Brush tool to bring out the white of the water in the falls and the sea.

I've shown where I painted the Brush Tool on this image here, with the adjustments I made shown to the right. 

Image 2: the sky

Then it was on to the image of the sky. This was much simpler and basically involved the adjustments shown below.

This screen shot shows how I used two Gradient Adjustments: (1) one vertical for the sky, with the settings shown (2) one horizontal one to try to reduce the light pollution from the street lamp.

Finally, it was over to Photoshop to blend the two images. This was quite straightforward and just involved the use of Layer Masks to gradually blend the sky into the foreground. There weren’t too many stars trailing into the fence at the top, so that job wasn’t as difficult as it might have been! I did other noise reduction techniques there using Nik Dfine, and added some final global levels adjustments, and the image was ready.

So, from imagination to realisation. The vision - and the technique. The two sides of the creative coin for astrophotography.

Other examples

Here are a couple more examples of this double exposure technique in action. 

The first I took just after the Dunseverick one. I headed to the Causeway cliffs to capture this one. Again, I had previsualised this shot, as I knew from a former photo I'd taken here that it can work very well if you have a person posing on the headland!

This time, I took an hour's worth of shots of the sky to produce the star trails image (see my previous eBook for more details on how to produce a shot like this). This gave me this image:

Causeway cliff aurora star trails (Large).jpg

As you can see from this shot, the foreground image comes out quite noisy. So, again, the double exposure technique can be used to good effect here. In fact, to realise my vision for this, I took a series of 6 portrait orientated shots and stitched them together in Lightroom to create a panorama for the land. The reason I did this was because I knew that I'd be face with a dilemma here: shoot to get the full sweep of the bay in, and I wouldn't get many stars for my trails. Shoot for the stars (as I have done) and I wouldn't get the full sweep of the bay.

But, with the pano for the ground merged with the sky shot above, I had the best of both worlds! All that remained was the final element - me standing on the headland with my torch. I used the wifi remote for my camera to see where I was positioned on my phone screen, triggered the camera - and stood very still for 30 seconds!

I therefore ended up with three images to be blended: sky, foreground and person. Again, this was done using Layer Masks in Photoshop, with a few final Curves adjustments to make the images blend nicely. 

The final image was taken just a few nights before the other two, when I managed to capture this image at the Causeway, again using two exposures to get the overall shot. I had actually hoped to capture those two images that night - but clouds stopped that fun! That allows me to say that there is another quality, alongside vision and technique, that you need for astrophotography: patience! But that's the subject of a whole other blog...


The ill wind part 1


The ill wind part 1

A three part mini-series on the visit of the Beast from the East this winter

‘Tis an ill wind that blows nobody any good’ goes the well known saying. This is, of course, totally true. Metaphorically speaking, you are indeed unfortunate if there are no positives in a set of initially negative circumstances.

The tabloid's nightmare

But it’s also true literally - especially if you are a tabloid headline writer. This winter in the UK, we’ve had not one but two visits from that illest of winds: the Beast from the East. Cue reports of end-of-the-world like apocalyptic outcomes - a veritable Snowmageddon - for the UK from the Daily Mail and the Daily Express. Of course, they are over-exaggerated nonsense, supported by supposed ‘experts’ who are nothing of the sort. But we lap them up. We click on the click-bait links. They get the revenue from us doing so. And the ill wind brings them plenty of good!

The photographer's dream

But it’s not just tabloid headline writers who rub their hands with glee at the prospect of the Beast from the East. For, us landscape photographers also find ourselves wishing for the good that accompanies this dreadful draught. We, you see, long for ‘proper’ winter in the UK. Not just the drab, damp overcast stuff that just makes you long for summer. But cold brings frost and snow - and these two things can transform our landscape into the most photogenic of beauties. Whilst we too may be sceptical of the extremes of the tabloid headlines, deep down there’s a part of us wishing that they were even a wee bit true.

The Beast visits the Mournes

Ryan Simpson surveys Trassey Track, with the cap clouds beginning to build over Bearnagh...

And so, it was with great anticipation that we awaited the first visit of the Beast in February. When first the winds swung round to the East, but before they had really taken hold, Ryan Simpson and myself headed for the Mournes. Placed as it is in the south east of our country, it’s one of the places that can benefit most from the easterly winds, as the air gets recharged with moisture over the Irish Sea, then rises, cools and condenses over the mountains to bring cloud and often snow.

The top of Bearnagh, as seen from the top of Slievenaglogh

This time, the air wasn’t yet quite cold enough for snow. But the east wind brought an amazing cap cloud over the top of Slieve Bearnagh. As we hiked up Slievenaglogh, we were treated to the most beautiful of cloud and light patterns. Glorious crepuscular rays of light danced across the top of the mountain all afternoon as the most gentle of soft light draped itself across the mountains in front of us.

Detail shot of the summit tors of Bearnagh. The line of the Mourne Wall is traced out by the snow from a previous fall that was yet to melt.

The soft light rests gently on Ben Crom reservoir

The lady of the lake...??

The whole display, courtesy of the east breeze, hung around all afternoon and into the sunset. It meant that our photoshoot was relaxed and unhurried. We were able to wander bewteen Slievenaglogh and Corragh, looking for the best angles and positions to allow us to make the most of this scene.

We even had time to jump over to the western side of the Mourne Wall for some shelter as we enjoyed a cup of coffee from the nicest of locations for coffee in the whole of Northern Ireland that day as we watched the most tranquil of sunsets. The sun even managed to settle down for the night in the saddle between Meelmore and Meelbeg, throwing off a little sunburst as a last hurrah in the process.

The wind may have been cold; it may have been flexing its muscles, a portent of what was to come. But, for that afternoon, for those moments, seeing the kind of light we have never before witnessed in the mountains, it was the most blessed of breezes indeed.

Next time, I’ll talk about what happened when the full blast of the Beast set in.


Mournes Photographic Workshops launched!


Mournes Photographic Workshops launched!

A funny thing happened this week. On my Facebook memories up popped something from this time last year: an announcement of my very first astrophotography workshop. Since then, I’ve run a series of workshops under the stars at the Causeway Coast, sharing something of my passion and enthusiasm for staying up really late and finding peace and solace under the vast canopy of the cosmos above me.

So why is this funny? Because today, exactly a year this week since my first workshop announcement, I am thrilled to announce a new and exciting workshop initiative, this time in my second home: the fabulous mountains of Mourne.

An exciting collaboration

But not only am I pleased about the chance to share something of the peace and solace I find up there with others. I am particularly excited about the fact that I will be doing this, not on my own, but with two of the Mournes photographers I hold in highest regard, and two guys who are some of my best mates: Ryan Simpson and Stephen Wallace.

We have decided to collaborate together to pull our experience and expertise, so that you can learn to see the mountains not only from one photographer’s perspective, but from three.

Between us, we have countless hours of experience hiking all over the mountains, in all seasons, and in all sorts of weather. We not only have come to know this place well; we have come to be truly at home here. We know the rhythms and seasons of the year. We know how the landscapes look under different light. And we have come to know the great inspiration it is to stand in the heart of the Kingdom of Mourne, looking up at an imposing peak, or looking down over the sweeping valleys below.

Experience the beauty, don't just see it

And so our plan is not just to show you around the mountains. But to help you to discover them. To begin the ongoing journey of you getting to know them, their character and their ebbs and flows through our workshops. Yes, you will learn the technicalities of photography. But, more than that, you will come to experience the breathtaking wonder that waits to be uncovered in this unique landscape in Northern Ireland.

Register your interest

At this stage, we are still in the planning phase. But we are keen to open this idea up at this point for anyone who would like to register interest. If you would like to do so, click on this link here and you can fill in a few details to be added to our registration list.*

Come and live the adventure with us in the place that inspired CS Lewis to imagine Narnia into life...


We are currently thinking of running the first workshop in April/May.


Some of the workshops will be in the High Mournes, some lower down, and possibly some seascape Mournes workshops.

Fitness Level

It depends on the workshop location. High Mournes would need an average to above average level of fitness and suitable hiking clothing and equipment. Others will be less physically demanding!

* Your email address will not be used for any other purpose, nor shared with anyone else


The beautiful ugly sister


The beautiful ugly sister

The is a particular vision of astro beauty that I am chasing. Not surprisingly, it includes the aurora, dancing in the skies above me - something I have been privileged to have witnessed many times in Northern Ireland. But this dream involves another ingredient found only on the coldest of cold aurora chasing nights - a snowy landscape below a starry sky above. I have visions of the vivid colour of a large aurora casting its eerie green glow on the gently undulating snow drifts in the fields in front of me. I have come close, once before. But, to me, it was only a taster of what I'm really after. I can see it in my head; and it looks awesome.

So, when there's even the remote chance of realising this dream, I have to spring into action. And so it was on a Monday evening early in December, with the snow lying fresh on the ground, with clear skies forecast for the heavens above, and with the chance of an aurora making an appearance at some stage, that myself and fellow astrophotography buddy Johnny Baird set off towards a favoured hunting ground at Slemish.

The roads were ice rinks. The journey up was challenging and involved more than one spin of the wheels on ground that simply refused to give up any semblance of traction. But carefully and slowly we wove our way to the little brook that flows off the flanks of this ancient volcano. The skies, as promised, were crystal clear and the stars quietly got on with their famous twinkling overhead. The snow was glistening with a sharp frost that had descended with the night, reflecting back so much light that we could see so clearly, even on this moonless night. And there wasn't a breath of wind; the only sound to be heard was the gentle gurgling of the little brook, as the water that had managed to escape the icy grip of winter tumbled and frolicked downstream. All we needed was for lady aurora to come out a dance for us. 

But she was playing hard to get that night. So hard, that it seemed that she hadn't even put her party dress on, never mind started to spin and twirl above us.

However, sometimes when the main act doesn't cooperate, it gives room for another character to emerge into the limelight. For, in the skies above, there was another celestial light display going on: airglow.

Causeway introductions

It was an amazing display in September at the Giant's Causeway that first made me fall for airglow.

Too often seen as the aurora's ugly sister ("That's not aurora, it's just airglow"), in actual fact this is a thing of tremendous beauty all in itself. Okay, so it may not reach the dizzying heights of an amazing aurora display. But that night at the Causeway I got to see what a proper airglow display looks like.

Waves of light, rippling across the sky, with an intensity that was bright enough to light the very ocean itself green in long exposure shots on the camera. I was blown away by the show, and I was hooked

My only regret that night was that I wasn't able to shoot a timelapse video. Just how dynamic are those ripples, I wondered. And I resolved myself to find out the very next opportunity I got!

I don't need to be asked twice

So, when I spotted the waves of airglow in the sky that night, I didn't need asking twice! Up went the camera, the intervelometer was set, and we stood back for the next hour whilst my camera did its work, enjoying looking out for a few early Geminid meteors in the starry skies above.

So here I present my very first airglow timelapse. And, if you've never yet seen just how much it moves across the night sky, then sit back and enjoy the aurora's ugly sister in all her glory!

"Not So Dark After All"

Free eBook on airglow

If you're interested in finding out more about what airglow is and how it occurs, check out my free mini eBook, "Not So Dark After All".


Not everything that is good is fun


Not everything that is good is fun

Not everything that is good is fun.

I must say, that's pretty much how I felt about life last night. I battled to the summit of Slieve Bearnagh yesterday for my first snow of the season. The forecast had suggested the snow line would be around 400m and, with showers expected over Friday night, there was a good chance the summits of the Kingdom of Mourne would be sprinkled in snow.

And indeed they were. The snow was fine. You can walk in snow. It was the ice on the way up that very steep and boulder-laden final push to the summit of Bearnagh. The rivulets of water that cascade down off the side of the mountain had begun to freeze as we pushed on up from Hare's Gap. As we went higher and higher, the froze more and more solid. At first, only the top of the water was frozen; but as we went higher, it all froze. The water, trapped in a never ending moment of time, clinging to the surfaces of the boulders - and making picking your way up arduous and treacherous.

And then there was the wind. The Met Office had said that, with the windchill, the temperatures on the summits would be a bone-chilling - 11 C. I had gone up prepared, layered up so much I looked like the Michelin Man! But even with all the gear, the wind was bitingly cold. If I took my gloves off at all to work my camera, my hands were getting numb within minutes. I could feel my cheeks beginning to tingle in the cold. I kept moving around, partly to take various photos, partly to keep warm!

Then there was the cloud. The tops of the mountains were shrouded in cap cloud, formed as the winds were forced up and over the peaks. Sometimes, the cloud gave hints it would clear, and hints of warm light came in from above. But it never did. Instead, here we were, wrapped up in this other world of snow and wind and cloud, enveloped in a land that felt far, far away, despite its familiarity.

Order in the midst of chaos In the cold and wind, the conditions were so harsh it was difficult to concentrate on basic things like composition. And that can be a problme on the top of Bearnagh. It's a very photogenic mountain summit. But, like many of the Mournes peaks, it's strewn with boulders, and the foreground can be very chaotic. Given that, I was very glad to stumble across this pleasing arrangement of rocks, forming an S-curve sweeping up to one of the main tors. One of the main goals of composition is to try ot bring about order from chaos. The apocolyptic conditions up there were chaotic enough - it was great to find this semblence of order!

This was not a time for the grand vistas - we simply couldn't see that far! Instead, I busied myself with trying to capture the mood of sheer brutality we were experiencing. Scenes draped in snow and ice, close up shots of those ancient granite tors, encrusted with ice, as they have been countless times over the millennia they have stood proud and resilient against the harshest of elements.

The Freedom of Constraint

I'm happy to admit that I'm a great fan of the grand vista shot. But, what happens when the cloud that has closed in on top of the mountain means you can'r see more than 30 metres away? There's no chance of any grand vista shots.

Sometimes constraint can be the very thing that bring liberty. In this case, the cloud forced me to look closer, at things that otherwise I might have overlooked. In this case, it was the forst encrusted tors. The patterns and shapes, along with the tonal contrasts of the dar baslat and the ice crystals, made for intruiging subject matter.

So I set about looking for lines and patterns and shapes, details hidden in plain sight.

Then it was time to descend. If the ascent had been hard, the descent was even more so. The icy conditions meant that every foot step had to be placed oh so carefully; routes had to be decided upon to avoid the frozen streams and had to be navigated with great care. We were so relieved to make it back down to Hare's Gap. But, of course, from there, there's still a good hour's hike back to the car. By now, it was getting dark, so the head torches came out. And so did the snow and hail. As our head torches shone into the falling snow, driven by the wind howling up the valley, it was like we were travelling in hyperspace in some spacecraft as the snow whizzed past us, stinging our cheeks for good measure as it did.

And finally we go back to the cars, too tired even to feel much by way of relief. As I sat in the car, quickly processing one of the shots I got on my phone, I was sore. I was cold. I was weary. I was not having fun.

And yet, I felt great. It was undoubtedly one of the most challenging hikes I've had up the mountains. And that's part of what made it so rewarding. Sometimes you can simply drive to a location and great a great photograph. But sometimes you have to push yourself, endure experiences that are painful and hard. And, if you do, the reward is even greater.

Not everything that is good is fun - and I wound't have it any other way!