The Ghostly Glow of Gegenschein


Northern Spring Sky Panorama

It takes a dark spring night to see it well, but now lurking near Jupiter is a ghostly sky glow called Gegenschein. 

This diffuse glow lies directly opposite the Sun. It is caused by sunlight reflecting off interplanetary dust particles in the outer solar system. They reflect light more effectively at the anti-Sun point where each dust particle is fully lit by the Sun.

Like the Sun, the Gegenschein moves around the sky along the ecliptic, moving about a degree from west to east from night to night. March and April provide good nights for seeing the Gegenschein as it then lies in an area of sky far from the Milky Way.

Even so, it is very subtle to the unaided eye. Look south at about 1 a.m. local daylight time.

However, this year, in early April the Gegenschein will be more difficult as it will then lie right on top of Jupiter, as that planet reaches its point opposite the Sun on April 7. Jupiter will then be superimposed on the Gegenschein.

The main image at top is a 7-image vertical panorama of the spring sky, from Corvus and Virgo above the horizon, up past Leo, into Ursa Major and the Big Dipper overhead. Spica lies below bright Jupiter, Arcturus in Böotes is at left, while Regulus in Leo is at right. The grouping of stars near centre is the Coma Berenices star cluster.

Orion over the Old Barn

Earlier in the night, I shot the sky’s other main glow – the Milky Way, as the winter portion of the Milky Way around Orion set into the southwest.

But over in the west, at the right edge of the frame, is the Zodiacal Light, caused by the same dust particles that create the Gegenschein, but that are located in the inner solar system between us and the Sun.

The Zodiacal Light is better depicted in images in my previous post from Dinosaur Park

We bid adieu to the winter Milky Way now. As it departs we are left with an evening sky without the Milky Way visible at all. As seen from northern latitudes it lies along the horizon.

But later in spring, late at night, we’ll see the summer Milky Way rising, beginning its seasons of prominence until late autumn.

— Alan, March 19, 2017 / © 2017 Alan Dyer / AmazingSky.com 

 

Glows and Streaks in the Spring Sky


The Spring Sky over the Pioneer Farmstead

How many sources of skyglow can you pick out here?

There are at least five:

• the Milky Way (at left),

• green airglow (below the Milky Way),

• all too prevalent light pollution (especially reflected off the clouds coming in from the west at right),

• lingering blue twilight across the north (at left and right), common in May and June from my northern latitude,

• and even a touch of aurora right at the northern horizon at far left.

In this scene from May 28, the Milky Way arches over an abandoned pioneer farmstead from the 1930s and 40s near my home in southern Alberta.

Mars (very bright and in some clouds) and Saturn shine at lower centre, while Jupiter is the bright object in clouds at right just above the old house.

Arcturus is the brightest star here at upper right of centre, made more obvious here by shining through the clouds. The Big Dipper, distorted by the map projection used in the this panorama, is at upper right.

Technical: This is a 360° horizon to zenith panorama taken with the iPano motorized panning unit, using the 24mm lens at f/2.8 and Nikon D750 at ISO 6400, for a stitch of 28 panels, in 4 tiers of 7 segments each. Stitched with PTGui. South is at centre, north to either end. The original is 25,700 x 7,700 pixels.

Just after I shot the panorama I captured the International Space Station passing directly overhead in one of several passes this night.

ISS Pass #2 (May 28/29, 2016)
The second Space Station pass of May 28/29, 2016, at 1:40 a.m., with cloud moving in adding the glows to all the stars. Taken with the 8mm fish-eye lens from home. The Big Dipper is high in the west at right. Mars is bright at bottom, to the south. Several other satellites are in the sky as well. This is a stack of 3 exposures, each 2.5-minutes with the camera on the Star Adventurer tracker.

At this time of year the ISS is lit all night by the Sun that never sets for the astronauts. We see the ISS cross the sky not once but several times in a night at 90-minute intervals.

While the sky near solstice is never dark at my latitude, it does have its compensations and attractions.

— Alan, May 29, 2016 / © 2016 Alan Dyer / AmazingSky.com

 

Capturing the Quadrantids


Quadrantid Meteor Shower Composite

The Quadrantid meteors streaked out of the northern sky on a fine winter’s night.

The temperature was mild and skies clear in the early evening for the annual Quadrantid meteor shower. This is a prolific but short-lived shower with a brief peak. The cold and low altitude of its radiant point keeps this shower from becoming better known.

This was the first year I can recall shooting it. I had some success during a 2-hour shoot on January 3, from 9 to 11 pm MST.

The result above is a stack of 14 images, the best out of 600 shot that recorded meteors. The ground and sky comes from one image with the best Quad of the night, and the other meteor images were masked and layered into that image, with no attempt to align their paths with the moving radiant point.

However, over the 2 hours, the radiant point low in the north would not have moved too much, as it rose higher into the northern sky.

Most of the meteors here are Quads, but the very bright bolide at left, while it looks like it is coming from the radiant, it is actually streaking toward the radiant, and is not a Quadrantid. But oh so close! I left it in the composite for the sake of the nice composition!

Light clouds moving in added the natural star glows around the Big Dipper stars.

All frames were 10 seconds at f/2 with the 24mm lens and Nikon D750 at ISO 3200.

— Alan, January 4, 2016 / © 2016 Alan Dyer / www.amazingsky.com 

Waterton Lakes by Moonlight


Cassiopeia and the northern stars over Red Rock Canyon in Waterton Lakes National Park, Alberta, with illumination from a waxing gibbous Moon. This is a composite of three 30-second exposures for the ground to smooth noise and one 30-second exposure for the sky, all with the 24mm lens at f/3.5 and Canon 6D at ISO 1600.

Mountain scenes take on a new look when photographed by moonlight.

Last week I spent four wonderful nights shooting the landscapes of Waterton Lakes National Park under the light of the waxing Moon. For two of the evenings I taught small groups of photographers eager to learn how to extend their photo skills into the night.

A nightscape photographer from one of my workshops, shooting in the moonlight at Red Rock Canyon, in Waterton Lakes National Park, Alberta. Clouds partly obscure the gibbous Moon but add a colourful iridescent corona around the Moon, which is reflected in the Red Rock Canyon Creek. This is an HDR stack of 5 exposures with the 14mm lens and Canon 6D, to preserve detail in the bright clouds and the disk of the Moon, and in the dark shadows.

We shot at Red Rock Canyon both nights, an ideal spot for its many composition options for shooting both toward and away from the Moon.

The lead image is a view looking up the canyon, with Cassiopeia in view. Always nice to have a recognizable constellation so well positioned.

The image just above looks toward the Moon, partly hidden by colourful clouds diffracting the moonlight. A student is at left trying out a composition.

Photographers at a Nightscapes Workshop at Red Rock Canyon in Waterton Lakes National Park, Alberta, June 2015, in the moonlight.

Here, students, silhouetted by the Moon, use the footbridge as their vantage point to photograph moonlight on the canyon waters and walls.

Alpine flowers in the moonlight at Red Rock Canyon, in Waterton Lakes National Park, with the scene lit by light from the waxing gibbous Moon. The “Matterhorn” style peak is Anderson Peak. This is a blend of two exposures: 30 seconds for the sky and 50 seconds for the ground, all with the 24mm lens at f/5 and Canon 6D at ISO 3200.

My workshops were part of the annual Waterton Wildflower Festival. So, a number of us tried to shoot flowers by moonlight, no easy task considering the wide apertures and shallow depth of field usually required, even under bright moonlight.

But the photo above is my take on summer alpine flowers in a meadow with the iconic Anderson Peak in the distance.

A panorama of the flower-filled Blakiston Valley on a moody moonlit cloudy night at Waterton Lakes National Park, June 24, 2015. The Big Dipper is at upper right, with its handle pointing to Arcturus at left of centre. Spica is at far left. A subtle halo surrounds the first quarter Moon which has just set behind Crandell Mountain at left.  This is a 9-segment panorama with the Nikon D750 and 24mm lens, mounted portrait, and stitched with Photoshop using spherical geometry and corrected with Wide Angle Adaptive Lens Correction to straighten the scene. Liberal use of Highlight and Shadow recovery in ACR and Shadows and Highlights in PS brought out the flower-filled foreground while retaining detail in the bright sky. Each segment was 30 seconds at f/2.8 and ISO 1600.

Three nights were wonderfully clear. But my first night, set aside for scouting locations for the Workshops, was beset by some clouds. However, I made use of them to create a moody moonlit cloudscape panorama of the Big Dipper over Blakiston Valley.

I’ll be back in Waterton in September for the Wildlife Festival. We won’t try to shoot bears by moonlight! One did wander by at the start of our Saturday Workshop!

Instead, we’ll concentrate on photographing the Milky Way. That’s Friday, September 18.

– Alan, July 3, 2015 / © 2015 Alan Dyer / www.amazingsky.com 

Nightscapes at Double Arch


Star Trails Behind Double Arch

The iconic Double Arch looks great under dark skies, moonlight, or painted with artificial light.

Last night, I returned to the Double Arch at Arches National Park, to capture a star trail series, starting from the onset of darkness at 9:30 p.m., and continuing for 2.5 hours until midnight, an hour after moonrise at 11:00 p.m. The lead image is the result.

I think it turned out rather well.

The Big Dipper is just streaking into frame at top right, as I knew it would from shooting here the night before. The bright streak at upper left is Jupiter turning into frame at the end of the sequence. Note how the shadow of the moonlit foreground arch matches the shape of the background arch.

On the technical end, the star trail composite is a stack of 160 frames, each 45 seconds at f/2.8 and ISO 3200, with the Canon 6D and 14mm lens. The foreground, however, comes from a stack of 8 frames taken toward the end of the shoot, as the moonlight was beginning to light the arches. An additional 45-second exposure taken a couple of minutes after the last star trail frame adds the star-like points at the “head” of the star trail streaks.

I used the excellent Advanced Stacker Actions from StarCircleAcademy to do the stacking in Photoshop.

Dark Sky Behind Double Arch

Before starting the star trail set, I took some initial short-exposure nightscapes while the sky was still dark. The result is the above image, of Double Arch in a dark sky. Passing car headlights provided some rather nice accent illumination.

On such a fine night I thought others might be there as well. Arches is a very popular place for nightscape imaging.

Sure enough, 6 others came and went through the early evening before moonrise. We had a nice time chatting about gear and techniques.

As expected, a few photographers came armed with bright lights for artificially lighting the arches. I kept my camera running, knowing any illumination they shone on the foreground wouldn’t affect my star trails, and that I’d mask in the foreground from frames taken after moonrise.

Photographer Lighting Double Arch

Here’s one frame from my star trail sequence where one photographer headed under the arch to light it for his photos. It did make for a nice scene – a human figure adds scale and dimension.

However, I always find the light from the LED lamps too artificial and harsh, and comes from the wrong direction to look natural. I also question the ethics of blasting a dark sky site with artificial light.

On a night like this I’d rather wait until moonrise and let nature provide the more uniform, warmer illumination with natural shadows.

Big Dipper over Double Arch

As an example, I took this image the night before using short exposures in the moonlight to capture the Big Dipper over Double Arch. When I shot this at 11 p.m. I had the site to myself. Getting nature to provide the right light requires the photographer’s rule of “waiting for the light.”

– Alan, April 7, 2015 / © 2015 Alan Dyer / www.amazingsky.com

Moonlighting at Monument Valley


Moonrise Behind the Mittens at Monument Valley (#1)

The Full Moon rises behind the famous Mitten buttes at Monument Valley.

I spent a fabulous weekend capturing sunsets and nightscapes at the iconic Monument Valley on the Utah/Arizona border, the photogenic outdoor set of dozens movies over the decades.

On the eve of the total lunar eclipse I shot the nearly Full Moon rising behind the West (left) and East (centre) Mittens and Merrick Butte (at right). On the evening of Friday, April 3 the Moon rose and sat amid the sunlit clouds with the Sun still up.

The alignment that would place the Moon directly opposite the Sun to create the eclipse was still 11 hours away.

Note how the butte’s shadows point almost, but not quite directly, at the nearly Full Moon. They point at the place in the sky the Moon would be before dawn at the end of that night.

Indeed, on eclipse morning on Saturday, April 4 the Moon set exactly as the Sun rose (see my photos in my previous blog).

But on eclipse eve the Moon rose 30 minutes before the Sun set, providing a chance to catch the Moon behind the still sunlit red buttes.

Moonrise Behind the Mittens at Monument Valley (#2)

I shot this image about 20 minutes after sunset on April 3, so the foreground is now in shadow but the Moon appears in a more richly tinted twilight sky.

Orion and Venus Setting at Monument Valley

Later on April 3 I captured this scene, with the Tear Drop and Rock Door Mesas now lit by a bright Full Moon, and with the stars of the winter sky setting into the west. Canis Major and Orion are at left, while Taurus, including the Pleiades star cluster and brilliant Venus, are at right.

The Orion & Venus image is a 2-panel panorama.

Moonbeams at Monument Valley

On the evening of April 4, clouds thwarted plans for a long star trail sequence above a moonlit foreground.

Instead, I shot toward the Moon and clouds, to capture subtle moonbeams radiating out from the Moon, now some 14 hours after the eclipse, rising behind Merrick Butte. I shot this from the dusty Loop Road that winds through the valley floor.

Big Dipper over West Mitten, Monument Valley

Instead of lots of images for a star trail composite, I was content to shoot this one image, catching the Big Dipper in a brief hole in the drifting clouds, hanging in the sky over the West Mitten butte. The foreground is lit by the partly obscured Full Moon. The long exposure streaks the moving clouds.

Night or day, it’s hard not to take a great photo here, clouds or not!

Sunset Panorama at Monument Valley

On my final evening at Monument Valley, high winds common to the area, blowing dust, and the closed Loop Road, scuttled plans again for long star trail sequences from the valley floor.

So on Easter Sunday, April 5, I settled for a panorama from the classic viewpoint showing the setting Sun lighting the buttes and mesas of Monument Valley.

It is an amazing place, but one that still requires patience to wait out the clouds and dust storms.

– Alan, April 6, 2015 / © 2015 Alan Dyer / www.amazingsky.com

The Old Hearst Church in Moonlight


The Big Dipper over Hearst Church

The Big Dipper and the Pole Star shine above the moonlit historic Hearst Church.

Tuesday was a productive evening of shooting in the moonlight. One of the best from the night pictures the Hearst Church in the rustic town of Pinos Altos in the Gila Forest of southern New Mexico.

The Big Dipper stars shine at right, with the Pointer stars in the Bowl aiming at Polaris above the Church. Illumination is from a waxing quarter Moon and from some decorative lights in the yard next door across the street.

The Hearst Church was opened in May 1898 and indeed is named for the famous Hearst family. Money to build the church was raised by the local mining families with a major donation from Phoebe Hearst, wife of the mining magnate and senator George Hearst. Phoebe was also mother to newspaper tychoon William Randolph Hearst, the inspiration for Orson Welles’ movie Citizen Kane. Gold that decorates Hearst’s mansion in California came from the family mine near Pinos Altos.

As the mining boom went bust the Methodist church lost its pastor then its congregation. It is now an art gallery and home to the Grant County Art Guild. See their website for details on the historic church.

While I know many of my blog’s followers enjoy the photos for their own sake, lots of folks also like to learn more about the technical aspects of the images.

So with this blog, and selected others in future, I’ll present a bit more of the “how-to” information.


How the Image Was Shot and Processed

Taking the image could not have been simpler. It is a single 45-second exposure at f/2.8 with the 24mm lens and Canon 6D at ISO 800, on a static tripod, about as basic as you get for nightscape shooting. There is no fancy stacking or compositing.

The trick is still in the processing, however. Here is a breakdown of the Photoshop CC 2014 file and its various layers. Every aspect of the processing is non-destructive. No pixels were ever harmed in the process. Every adjustment can be tweaked and modified after the fact.

Heart Church Processing Layers

< Star spikes top layer added with “Astronomy Tools” actions from Noel Carboni.

< Sharpening layer created from stamping the final layers into one layer using the Command-Option-Shift-E command, then a High Pass filter applied, blended with Soft Light and masked to sharpen just the ground.

< Adjustment layers for colour, brightness & contrast, and levels, applied to the sky and ground separately with masks, created using Quick Selection Tool and Refine Edge.

< A Clone & Heal layer for wiping out the power lines & power pole, using the Patch & Spot Healing Tools.

< The base image, opened from the developed Raw file as a Smart Object, with noise reduction and sharpening applied as Smart Filters.

I know this won’t explain all the processing steps but I hope it provides some idea of what goes into a nightscape.

All this and much more will be explained in an upcoming half-day “Photoshop for Astronomy” Workshop I’m presenting Saturday, May 9. If you are in the Calgary, Alberta area, consider joining us. For details and to register, see the All-Star Telescope web page

Also, my ebook featured below has all the details on shooting and processing images like these.

Clear skies and happy shooting!

— Alan, January 29, 2015 / © 2015 Alan Dyer / www.amazingsky.com