The Northern Lights at the Old Larson Ranch


Aurora at Larson Ranch Panorama

The northern lights dance, and light the pioneer homes at the old Larson Ranch in Grasslands National Park.

What a night this was! I arrived at the Larson Ranch site in the Frenchman River valley to shoot some Milky Way panoramas, when, right on cue, the aurora broke loose.

Some aurora had been there since nightfall as a diffuse arc, but about 11 p.m. local time (Central Standard Time in Saskatchewan) the curtains began to dance and pulse with activity as a sub-storm hit, raining solar particles onto our atmosphere from down the magnetic tail of the Earth.

The aurora glow lit the old pioneer buildings of the Larson Ranch, one of the stops on the scenic backroad drive through the Park.

The Larsons ran their ranch by the Frenchman, or Whitemud River, from the 1920s until 1985 when they sold their ranch to the National Park system, forming the first land for the new Grasslands National Park.

The house at left is the original home of cowboy author Will James, who lived here for a time working on ranches in the valley before moving to the United States. He was from Quebec, where he was Ernest Dufault.

I shot this 360° panorama using a 15mm lens, shooting 8 segments at 45° spacings, each a 1-minute exposure at ISO 2500 and f/3.2 with the Canon 6D. I used PTGui software to stitch the segments into a equi-rectangular projection pan.

– Alan, August 28, 2014 / © 2014 Alan Dyer

 

 

Prairie Sunset Panorama


Prairie Sunset Panorama

What a spectacular sunset tonight. The Sun is just going down in a blaze of red, while the waxing Moon shines in the deep blue twilight.

I grabbed the camera fast when I saw this happening out my front window, and raced out to the ripening wheat field across the road.

The top image is a 360° panorama of the sky, with the Sun at right and the Moon left of centre. The zenith is along the top of the image.

I used a 14mm lens in portrait mode to cover the scene from below the horizon to the zenith, taking 7 segments to sweep around the scene.

You can see the darkening of the sky at centre, 90° away from the Sun, due to natural polarization of the skylight.

Red Sun in a Prairie Sunset

I shot this sunset image a little earlier, when the Sun was higher but still deep red in the smoky haze that has marked the sky of late. It certainly gives the scene a divine appearance!

This is a 5-exposure high-dynamic-range composite to capture the tonal range from bright sky to darker ground, the wheat field. I increased the contrast to bring out the cloud shadows – crepuscular rays.

I boosted colour vibrancy but didn’t alter the actual colours – it was a superb sky.

I used PTGui v10 to stitch the panorama at top and Photomatix Pro to stack and tone the HDR set. While Photoshop is wonderful it did not work for assembling either of these images.

– Alan, August 6, 2014 / © 2014 Alan Dyer

 

The Galactic Archway of the Southern Sky


Two Styx Night Sky Panorama (Rectilinear)

The southern Milky Way arches across the sky, with the centre of the Galaxy overhead at dawn.

This was the sky at 4:30 this morning, as Venus rose in the east (to the right) amid the zodiacal light, and with the Milky Way soaring overhead. This image is a 360° panorama of the scene, with the zenith, the overhead point, at the top centre of the frame.

The location is the Two Styx Cabins, on the border of New England National Park in New South Wales, Australia. The cabin with the light on (I left it on on purpose for the photo) is where I stayed for two nights in splendid isolation.

The panorama is a stitch of 6 frames shot with an 8mm fish-eye lens, each 1-minute exposures on an untracked tripod. I used the PTGui software program to assemble the pan.

Below is an alternative rendering, in spherical format, to create the more classic “fish-eye” view, but one extending well below the horizon. So this is not one image but a stitch of six.

Two Styx Night Sky Panorama (Fish-Eye)

In this version you can more readily see the spectacle of the Milky Way at dawn in the southern hemisphere autumn months, with the bulge of the galactic core directly overhead as seen from this latitude of 30° south. It is a wonderful sight.

This is my last view of it for this trip. Till next year!

— Alan, April 11, 2014 / © 2014 Alan Dyer

 

The Great Arc of the Milky Way


Milky Way Panorama (Sept 4, 2013)

The Milky Way sweeps in a great arch of light across the sky.

It’s been a wonderful week for shooting the Milky Way. I had a very clear night on Tuesday but ventured no further than a few hundred feet from home to the harvested canola field next door.

The Milky Way was beautifully placed, as it always is at this time of year, right across the sky from northeast to southwest, with the starclouds of Cygnus passing directly overhead.

The top photo is a panorama of 8 shots, with a camera on a tripod, and each exposure being just 60 seconds with a 14mm lens in portrait orientation. I stitched the segments with PTGui software, rendering the scene with its spherical projection mode which wraps the dome of the sky onto a flat surface in a way that retains the zenith detail as your eye saw it, but greatly distorts the extremities of the scene at either end.

My house is at lower right.

Milky Way over Harvest Field (Sept 4, 2013)

For this image, I used the same lens to take a single view from horizon to well past the zenith. Here the camera was tracking the stars for a set of stacked 5-minute exposures to grab even more detail in the Milky Way.

What stands out as much as the Milky Way are the green fingers of airglow stretching across the sky. These were invisible to the eye but the camera sure picks them up.

Airglow is caused by oxygen atoms, in this case, fluorescing at night as they release some of the energy they absorbed by day. It’s not aurora and generally covers more of the sky, sometimes with a diffuse glow or, as here, with more structured bands that slowly shift over minutes. It varies from night to night and can occur at any latitudes. But usually only cameras pick it up. To the eye, airglow just makes the sky look inexplicably a little less dark than you think it should be on such a clear night.

– Alan, September 7, 2013 / © 2013 Alan Dyer

 

The Colour of Dark


Colors of the Dark Sky Panorama

What colour is the dark night sky? Depending on conditions, it can be any colour you want.

I shot this 360° panorama last night from my backyard under what looked like a clear and fairly dark, moonless sky. Looks can certainly be deceiving. The camera picked up all kinds of colours the eye couldn’t see.

Let’s review what’s causing the colours:

• To the north just left of  centre the horizon is rimmed with a bright yellow glow from all-night perpetual twilight present around summer solstice at my mid-northern latitude.

• Above that shines a green and magenta band from a low-level aurora just visible to the naked eye.

• Much of the sky is tinted with bands of green from ever-present airglow, caused by oxygen atoms at the top of the atmosphere giving off at night some of the energy they absorbed by day. I had thought the sky would look blue from the perpetual twilight but the airglow seems to overwhelm that.

• Yellow glows around the horizon at left (west) and right (southeast) are from urban light pollution from towns 50 km away.

• Some strands of remaining cloud from a departing thunderstorm add streams of brown as they reflect lights from below.

• Finally, the Milky Way shows up in shades of yellow and pale blue, punctuated here and there by red patches of glowing hydrogen hundreds of light years away.

The only thing missing this night was a display of electric blue noctilucent clouds.

The sources of most of these colours are an anathema to observers of faint deep-sky objects. Aurora, airglow and certainly light pollution just get in the way and hide the light from the distant deep sky.

A word on technique:
I shot this panorama using an 8mm fish-lens to shoot 8 segments at 45° spacings. I used the excellent software PTGui to stitch the segments together, which it did seamlessly and flawlessly. Each segment was an untracked 1 minute exposure at ISO 3200 and f/3.5. The panorama covers 360° horizontally and nearly 180° vertically, from the ground below to the zenith above. It takes in everything except the tripod and me!

– Alan, June 8, 2013 / © Alan Dyer