Photoblog 2.0

Imagine photographing stars and star trails under the clear night skies of the Eastern Sierras with the guidance of two masters of night photography! Under the auspices of Star Circle Academy, www.StarCircleAcademy.com, the Alabama Hills Star Circle Workshop will be a chance to hone your night photography skills, learn new skills both behind the camera and in the digital darkroom. You’ll come home with spectacular, unique images based upon the stunning clarity and unusual topography of California’s Eastern Sierra and the autumnal night skies.

The workshop will be based in Lone Pine, California and will use the Alabama Hills area, with its background of Mt Whitney and the High Sierra crest, as the primary shooting location. You can register now with an early-bird discount or get more information about the workshop.

Starry Night 3, photo by Harold Davis. Original story about this photo.

The Alabama Hills Star Circle Workshop is for anyone who wants to learn more about the exciting world of night photography, or who wants to take their night photography to the next level. The workshop is geared to provide specific information about photographing star trails using an intervalometer (a programmable timer) and using stacking software to create a single composite low-noise image of star circles.

Here are some links for more information: Star Circle Academy; Information about Alabama Hills Nov 5-7 workshop; Workshop syllabus (PDF); Registration.

Tuition is $425 if you register by September 11, 2010, $500 if you register by September 30, 2010, and $600.00 thereafter. Click here for more details or to register.

Based on past experience, we expect this workshop to sell out as it is strictly limited to 20 participants. A waiting list will be available once the workshop fills.

Class room portions of the workshop will be conducted at the Best Western Frontier Motel in Lone Pine, California where rooms are available to workshop participants at a discounted rate of $80 per night.

I am lucky to have my friend Steven Christenson as the co-leader of this workshop. Steven is a geek by day and a photographer, hiker, backpacker and magician by night. He is also a co-founder and an organizer of the very successful Bay Area Night Photography group where like-minded, low-light photographers find interesting subjects and challenges. Those who have been lucky enough to photograph with Steven know that he is generous with sharing his knowledge—and a great deal of fun!

Steven’s love of astronomy, technology and photography have found an outlet in night photography, especially star trails. Steven is expert at photographing star trails and his images have been selected by the Greenwich Royal Observatory for the short list for the Astronomy Photographer of the Year, 2010 competition. He has built custom components to power a camera for all-night unattended shooting. Steven freely shares his knowledge of astronomy and software tools for choosing the best celestial subjects, weather, dates and vantage points to capture everything from star trails to unusual astronomical events.

Please consider joining us for what will be a glorious and fun nightime adventure—not to mention highly educational.

Low Tide at Dusk, photo by Harold Davis. View this image larger.

This is an image taken in the China Beach area of San Francisco Bay as dusk was fading into night. The scene shows mud flats at extreme low tide, facing northwest on an overcast mid-winter evening.

I shot bracketed originals and combined six exposures in Photomatix, with some additional hand layering on top in Photoshop. By eye, the scene was more gray than blue—but each of the original frames shows distinct blue tonality.

For comparison, here’s a monochromatic version of the scene:

View this image larger.

Here’s an HDR image looking in the opposite direction:

View this image larger.

Related story (same location): Lonely Islet.

Mission Peak Sunset, photo by Harold Davis. View this image larger.

On Thursday evening Steven, Eric, and I took the “steep trail” up the flanks of Mission Peak (above Fremont, California). Steven’s goal was to set his camera up to take continuous 30 second star exposures over night. He planned to retrieve his gear the next day. The concept worked, the camera was still there, and the time lapse imagery, particularly the “Dazzler” section, makes for fascinating viewing. Check out the airplane trails in this star stack of Steven’s.

On the hike we came across some toads, a snake skin, and some mortar holes to pound grain used before there was a Silicon Valley. Mosquitos bit, I got a few touches of poison oak, and the steep trail lived up to its name. All in all, par for the course for a dramatic night hike in California in the summertime.

What I enjoy most about Mission Peak is the paradoxical sense of being both present and remote. The city is spread about below like a glittering river of lights, but the slopes of the mountain are serene and for the most part empty.

These two shots are HDR—High Dynamic Range—composites, each from five bracketed exposures. I put the bottom layers together using Adobe Photoshop’s Merge to HDR Pro. Mostly, this didn’t give me the tonal values I was looking for—so I manually layered in the earth and sky over the autoblend HDR backgrounds. My idea was to present the contrast I’ve mentioned between the remote and serene slopes of the mountain and Bay area civilization, apparently remote below—but actually only a few miles away.

View this image larger.

Faking Star Trails, photo by Harold Davis. View this image larger.

I faked these star trails. Meaning that this image is not based on an exposure, or combined composites of exposures, long enough to produce the star trails shown. The simulated star trails are an effect created in Photoshop from a single, relatively short exposure.

Ron Larsen, who attended one of my night photography workshops, pointed me to the Star Trails action in Photoshop CS5 Standard Edition. This action takes a single, static shot that includes stars at night and adds apparent motion to the stars in the form of trails. The best demonstration is given by Russell Brown in a video part way down this page of his Photoshop CS5 tips. The action works by successively copying and rotating the base layer of the photo, then compositing the stack of rotated layers together.

There are some gotchas to using this action. First, it just ain’t natural—meaning this is merely a mechanical rotation rather than the real astronomical movement of the stars. More on this point later, but the simulation works pretty well if your camera is pointed due north, where the movement of the stars is pretty much curved around Polaris (the North Star). In other words, pointing due north the simple curvature model is pretty close to reality; however, in other directions this simple model fails fairly drastically.

Another issue is that the stars in the photo need to be rendered as points. If the stars show motion by being elongated as trails before applying the action, then the action will create trapezoidal shapes in the sky, because the entire length of the original star trail is being reproduced in two-dimensions.

This probably implies an exposure time of three minutes or less, possible at dusk before deep night comes on, or when the night is dark by substantially boostin the ISO. Both approaches have issues—a higher ISO implies more noise, and a star shot at twilight means that the easy layer blending the Mr. Russell Brown shows in his video is not really possible (the Screen blending mode only works in his cute example because of the near-Black background color of the sky).

But qvetching aside, it is possible to get some attractive images using the Star Trail action. For example, I’m pretty pleased with the image shown at the top of this story. If you are interested, it was created from this three minute exposure I made a couple of years back. Blending of the foreground and the “faked” star trails layer was done using a layer mask and a gradient, along with some hand painting on the layer mask.

I’m pretty pleased with the way the fake star trails came out, but it does lead to a moral question, or, dare I say it, a question of moral hazard. To get “actual” trails as long as the ones shown here would have taken somewhere between 20 and 40 minutes of exposure time and a great deal of patience. It doesn’t seem fair to be able to get attractive results without the same amount of effort.

Here I am somewhat hoisted on my own petard. I’ve declared a number of times that images should be judged on how they come out, not the technique used to create them.

It’s my considered opinion that work done in Photoshop is just as valid as work created solely in-camera. Following this logic, though purists may not agree, I have to conclude there is a place for faking star trails—although the technique has to be done with care so that it isn’t obvious. And nothing will replace the feeling of shooting through the night and coming home with a perfect composite for stacking of the stars wheeling through the heavens on their journey through the night!

Update: It turns out that there are several ways to tell fake star trails from the real thing:

• Steven Christenson points out that what the Photoshop action doe is to circle around the center of the image. Only if one exactly centered the exposure on the north celestial pole and then used the action would you get something that would be correct for a perfectly rectilinear lens. You can easily see if you compare my fake star trail image with the original on which it is based on that the stars are circling around the image center rather than north.
• A close-up examination of the fake star trails at high resolution shows they are formed differently from actual stacked composite star exposures. The fake trails are not curvilinear: there is a chunky looking step-out at the pixel level representing the duplication and changed position of successive layers created by the action.

For more on stacking—the real thing—check out my blog stories Star Trails over Drakes Bay and Stacking Star Trails. You’ll find complete instructions for making photos of star trails, and how to use an interval timer, in my book Creative Night: Digital Photography Tips & Techniques.

Star Trails over Drakes Bay, photo by Harold Davis. View this image larger.

I made this image as a demonstration of star stacking for a recent night photography workshop I gave on Point Reyes. Before I explain how I made this image, you might be interested in some general information about star stacking, my workshop schedule, and what participants have said about my workshops.

Here’s the back story: Usually, a highlight of the Point Reyes night photography workshop is a visit after dark to the Point Reyes Lighthouse. Unfortunately, high winds forced the Park Service to close the stairs down to the lighthouse. I took the workshop group over to the platform above the Lighthouse, hoping that it might be relatively sheltered—but, no go. The platform was intolerably windy, and not conditions under which one could set up a tripod for stability.

So we went down to Drakes Beach, and sheltered on the leeward side of the bluffs, photographing moonlight on the waves. Fairly early—by night photography standards—we headed back to the historic Coastguard Boathouse, workshop central for the weekend.

From the Boathouse side of Drakes Bay, I noticed that things were fairly clear. There was also some shelter from the wind on one side of the building and a straight shot north. I dropped an extension tube out the window of my bedroom, attached a DC converter to run my camera, and positioned the camera in the corner of the building. I threw my 10.5mm digital fisheye lens on the camera to get as wide a field of view as possible, and also to maximize the star trails.

Workshop parrticipant and photographer Mark Lohman came outside to help me frame the image, but neither of us could really see anything in the dark. So I ran off a high ISO test shot at 30 seconds, f/4, and ISO 2,500.

The test exposure looked pretty good—maybe a little on the bright side—so I figured that 4 minutes at f/4 and ISO 200 would work fine for the real thing. This is about what I had expected, but it was nice to have it confirmed before firing off several hours worth of exposures—also, the test allowed me to confirm the composition. Note that I centered the composition on Polaris, the North Star, to get the most circular star trails.

Before making the exposures, I used my Bulb setting and my interval timer to make an exposure that I planned to use later for the foreground at 8 minutes (also at f/4 and ISO 200):

There was a small airplane fooling around in the sky (the swooping line) but this didn’t really matter as I was only going to use the exposure for the foreground.

Next, I used my interval timer to make 40 4 minute exposures. The interval timer settings were: no interval before exposures started; exposure length 4 minutes; interval between exposures 4 minutes and 1 second (unintuitively, on my timer this runs from the start of the previous exposure, not its conclusion); 40 repetitions.

Then I went to bed, listening to the wind howl outside and the waves crashing.

I woke some time in the middle of the night (I didn’t have a watch) and threw on the minimum of clothing. Outside, wind was still blowing, but camera and tripod still seemed to be in position. The 2 hours and 40 minutes of exposures had finished. I brought my camera back inside and went to bed.

Running through the captures in slide show mode was kind of like a “flip book”—because I could see the stars wheeling in the heavens around Polaris (the North Star). Here’s the way a pretty typical exposure looked when I viewed the set in Adobe Bridge:

Looking through the captures, I saw that the pier was lit a couple of times, once when a couple of workshop participants who’d stayed a little later at Drakes got home and the car headlights shone briefly on the pier, and once when someone was fooling around with light painting the pier. Here’s the headlight frame:

In the classroom, I made obeisance to the Photoshop Gods with the hope that the process would actually work. I opened the 40 images via Adobe Bridge, applying the same setting to eash one in Adobe Camera RAW (ACR). Next, I showed how to open the Statistics Script (avaibale in the extended versions of CS3 and later).

I added the 40 open files in the Statistics dialog and chose the Maximum method for combining the images. Then the workshop had lunch while my laptop chugged its way through the massive processing this required. Here’s the background that resulted:

You can see in the background that the frame in the stack with headlights lightened the pier, but the rest of the foreground needed some work. I finished the image by layering in the 8 minute exposure to use as a foreground, adjusting the colors, and selectively sharpening—with the results shown at the top of this story and below.

Star Trails over Drakes Bay, photo by Harold Davis. View this image larger.

San Francisco Moonrise, photo by Harold Davis. View this image larger.

I learned from my friend Steven Christenson that the full moon would rise shortly after sunset, in theory lined up from Battery Yates on Fort Baker directly behind the Transamerica building in downtown San Francisco. Steven posted a note to the same effect with the Bay Area Night Photography Meetup group—and when I got to the site there was already small crowd of night photographers gathered, cameras and tripods ready. This was night photography as a kind of group sport, and the companionship was fun while we waited for the moon to rise and added layers to protect against the chill.

The alignment of the moon seemed more or less as calculated, however the line of clouds kept it from appearing quite as low in the horizon as I would have liked. By the time it broke the clouds it was above rather than behind the Transamerica tower as you can see in the shot.

I used a 400mm lens (600mm in 35mm terms on my D300). To keep camera shake down in the breeze—a serious issue with this long a lens—I hung my camera back on the center pole hook as a weight. I also boosted the ISO to 400, taking the trade-off of a bit more noise in exchange for a faster shutter speed to reduce softness from camera motion. I shot the moon at 1/30 of a second and the foreground at 1/2 of a second, and combined the two exposures in Photoshop.

Exposure data: Nikon D300, 400mm, 2 combined exposures at 1/30 of a second and 1/2 of a second, each exposure at f/5.6 and ISO 400, tripod mounted.

Van Ness Avenue, photo by Harold Davis. View this image larger.

Standing on the median strip of Van Ness Avenue in front of San Francisco’s City Hall, I used a longish exposure—in the seconds but not the minutes– to capture moving car lights. I find an exposure time of between two and ten seconds often works best with most moving cars at night if there is some ambient light around, as in a cityscape (this was a five second exposure).

It’s amazing the difference in the way a place looks at night as opposed to day—and you never really know the night view until you shoot it.

There’s a round-up of some of my car lights at night images in Line Dance; for a car light image on a country road (and a longer exposure) check out (the logically named) Country Road; for more about night photography techniques generally see my book Creative Night: Digital Photography Tips & Techniques.

Lines and Shadows, photo by Harold Davis. View this image larger.

In a monochrome, life is about edges, lines, and dark (black) or light (white) masses of shapes. The interplay of these elements will make or break your composition without color to beguile.

Shadows thus become extremely important. In a color photo, most of the time a shadow is, well, merely a shadow. On the other hand, when you start to see monochromatically, a shadow is every bit as significant as the thing itself that is casting the shadow.

In landscape, during the day, shadows are mostly determined by the position of the sun, presence of clouds, and other ambient factors. At night, everything is different. As in this photo taken near San Francisco’s City Hall, street lights cast shadows in a direction—and with a relative intensity—that you wouldn’t see during the day. Since ambient light levels are low, even relatively dim lights can cast a big shadow, making for interesting compositions that wouldn’t be possible during the day.

Related image (using the night shadows created by street lights and trees): Trees in the Fog, the cover photo of Creative Black & White.

Mare Island Night Photo Shoot, photo by Harold Davis. View this image larger.

This light painting extravaganza took place during my night photography shoot on Mare Island sponsored by Renegade. The big impact of relatively small lights at night has to be seen to be believed. This was great fun, and a great group of shooters.

More Mare Island.

Rift in the Clouds, photo by Harold Davis. View this image larger.

New Year’s Eve featured a blue moon rising early, but the layers of fog and clouds that swept over San Francisco Bay made a capture seem unlikely.

When the moon made a brief appearance through a rift in the clouds I was ready, with an exposure biased towards the moonlight. The composition is based on the idea of letting everything besides the moon and its light on the water go pitch black. And also on the aesthetic pleasures of grain, er, I mean noise.

Exposure data: Nikon D300, 65mm, 1/30 of a second at f/5.0 and ISO 3200, hand held; yes, folks, you read that right, ISO 3,200. Look ma, no tripod.

City Dreams, photo by Harold Davis. View this image larger. Read the original story featuring this image.

Night Lights, a story about my night photography, is running on the Nikon USA website in the Insight & Techniques section of Learn & Explore.

Point Bonita by Moonlight, photo by Harold Davis. View this image larger.

By the strong light of a waxing gibbous moon I photographed the outer Marin Headlands coast, looking south towards the Point Bonita Lighthouse, the Golden Gate straits, and the lights of San Francisco’s outer sunset district.

The final image is a composite combined in Photoshop based on three exposures. All three exposures were taken with my Nikon D300 at 56mm using a tripod. The variations were 1 minute at ISO 200 for the darkest areas, 1 minute at ISO 100 for midtones, and 30 seconds at ISO 100 for highlights. I used the in-camera exposure histogram to judge the exposures because the display on the LCD of a RAW image captured in these conditions is inherently unreliable.

Cienfeugos Sunset, photo by Harold Davis. View this image larger.

These two images were captured from the seventh floor balcony of the Hotel Jagua in Cienfeugos, Cuba.

Cienfeugos is a relatively prosperous city by Cuban standards, as you can see in the sunset view of the place. I created the image from five captures with shutter speeds ranging from 1/80 of a second (darkest) to 1/8 of a second (lightest). I combined the captures in Photoshop using layers and masking.

I didn’t use software specifically intended to create HDR imagery, but the hand combining I used here is an example of hand HDR. Contrary to what some people seem to think, you don’t need to use Photomatix or Photoshop’s Merge to HDR to create HDR imagery—and HDR can look relatively natural. See Tone Poem for a comparison of Hand HDR and Photomatix.

The night photo is of the Palacio del Valle, a rather tasteless neo-Moorish confection at the end of the Punto Gorda peninsula in Cienfeugos. The Palacio is now a restaurant and nightclub.

If you are wondering where the power for all the lights is coming from, look no further than the view of Cienfeugos (above). In the distance, a power generator is burning cheap Venezuelan crude and belching smoke into the sky.

View this image larger.

Malecon Moon, photo by Harold Davis. View this image larger.

I shot this view of the Malecon in Havana, Cuba from the small bluff that the Hotel Nacional sits on. (More about the Hotel Nacional later.)

The two minute exposure gave the clouds a chance to spread out and show their colors in the moonlight. This exposure would have blown out the Malecon itself in the foreground of the photo, so I used a layer mask and a gradient to combine in a darker version shot at 20 seconds.

You can see a row of people living their life along the Malecon sea wall. But the long exposure has “flattened” them in some strange visual way—so even the people seem to be merely accessory to the landscape.

El Malecon, photo by Harold Davis. View this image larger.

Night comes to El Malecon, the boulevard that runs along the ocean. Old Havana glimmers in the distance. Soft light and surf spray in the air soften decrepitude. Lovers meet, music plays. You’d never know this isn’t the good life.

Exposure data: Nikon D300, 65mm, 30 seconds at f/11 and ISO 200, tripod mounted.