star stacking

How I Got the Shot: Light Painting and Star Trails at Devils Tower

Stars at Devils Tower. Nikon D750 with a Zeiss 15mm Distagon f/2.8 lens. Ten stacked frames, each shot at 150 seconds, f/2.8, ISO 1600 (1,500 seconds total).

The Conditions

Shooting under moonless conditions can create consistent challenges for astro-landscape photography. The primary challenge is lighting your main subject. When it’s the Devils Tower in Wyoming, you’ve gotta get it right.

Gabe and I were leading a group of eager learners on a workshop a few years ago when I made the above image.

I was not standing at my camera—I was up at the base of the Tower, illuminating it.

So how did we do this?

The Shoot

Well, lemme first show you how it looks without being lit, which you can see in Figure 1.

Figure 1. Nikon D750 with a Zeiss 15mm Distagon f/2.8 lens. 150 seconds, f/2.8, ISO 1600.

It lacked the detail that screams, “Is that the mountain from that famous movie?!?” Right? Yeah.

But one frame did stand out: when some climbers who had to descend after dark illuminated the deep crevices that are the hallmark of this natural stone edifice (Figure 2).

Figure 2. Nikon D750 with a Zeiss 15mm Distagon f/2.8 lens. 30 seconds, f/2.8, ISO 6400.

Aside from that, we wanted more detail in the Tower. So I set my intervalometer to take many, many (infinite, in fact) exposures. (You can read more on how to do that in our post “Mastering the Intervalometer for Night Photography and Long Exposures.”

I knew I intended to make an epic star trail from this. So I aimed for longer exposure lengths of 150 seconds and let the sequence begin. I knew this was still short enough to manage the long exposure noise that the camera would generate in the mid-August Wyoming heat.

I grabbed a two-way radio and drove up to the parking lot. I hit the loop trail and started doing my own lighting. From so far away from the camera, how did I know I was executing the light painting sufficiently? That’s where the radio came in—I kept pinging Gabe to see if my flashlight was providing proper detail and coverage. Trusting Gabe to be the lighting director from the camera position was crucial.

Gabe advised me to cover about one-quarter of the arc around the base of the Tower. We tried a few variations and settled on a final strategy (Figure 3).

Before and after light painting from the base of the tower.

I shot many different variations (Figure 4) through the evening, sometimes re-framing, sometimes adjusting the exposure length. Even when you’re confident about your approach in the field, it’s always good to push the boundaries of your decisions and to give yourself more options to look at when back at the computer.

Figure 4. The different strategies I shot that night gave me lots of options to choose from in post.

The Post-Production

The final set of frames I chose to work with is this:

Figure 5.

Each image required a gradient for the sky, and a proper Range Mask set to 28/100 Luminance and 19 Smoothness. I also used the mask brush to remove the gradient from Devils Tower itself and from the trees below.

Once the mask was done, I made the adjustments, which were intended to emphasize (but not over-process) the sky. Sometimes that’s a fine line, and one we always want to be conscious of. You can see the mask I created in Figure 6, and the adjustments in Figure 7.

Figure 6.

Figure 7.

Then I needed to stack the frames in Photoshop. In several previous How I Got the Shot blog posts we’ve discussed stacking frames to create star trails and to combine different light-painted compositional elements into one image. This time I used the same technique to achieve both those goals in one photograph—i.e., to get the stars to trail and the light-painted sections of the Tower to composite.

The process is:

  1. Select all the pertinent frames in Lightroom by shift-clicking the first and last.

  2. From the menu, choose Photo > Edit In > Open as Layers in Photoshop.

  3. Once the image opens select all the layers by clicking on the top layer, pressing the shift key and then clicking on the bottom layer.

  4. In the Blending Mode dropdown above the layers (the box that defaults to saying Normal), choose Lighten.

  5. Save and close, which will bring the stacked image back into Lightroom where you can make final edits.

I was really pleased with the stacked result:

Nikon D750 with a Zeiss 15mm Distagon f/2.8 lens. Ten stacked frames, each shot at 150 seconds, f/2.8, ISO 1600 (1,500 seconds total).

The photograph has more mystery with the tree line falling into silhouette and the Tower having detail. This emphasizes where the viewer should look.

A Little Cleanup

Due to some people’s red headlamps and flashlights, the trees and ground closest to us picked up the color. It’s quite hard to edit away, so I brushed in some local adjustments subtracting highlights and whites. After stacking, that still wasn’t enough, so I ended up using layer masks to eliminate the distracting details.

(Hmmmm. Come to think of it, it may have been the brake lights of my rental car when I returned to the group. D’oh! And possibly a “mea culpa” moment. Whoops. Bad Matt.)

When I re-edited the stack this time, I noticed something new. I wanted to crop it to a vertical. It felt … more powerful. More focused.

The final, final result:

Nikon D750 with a Zeiss 15mm Distagon f/2.8 lens. Ten stacked frames, each shot at 150 seconds, f/2.8, ISO 1600 (1,500 seconds total).

Wrapping Up

I gotta say, I am excited to return to the Devil’s Tower with Chris later this year. It’s going to be amazing. What will he and I dream up together? And what will the workshop participants dream up? I bet it’ll be out of this world. (Yeah, I went there.)

How do you achieve better astro-landscape photography by collaborating with friends and peers? Tell us more in the comments, and show us photos!

Note: Want to join Matt and Chris to make epic night photography images at Devils Tower National Monument? We have two spots left for the workshop, so sign up now!

Matt Hill is a partner and workshop leader with National Parks at Night. See more about his photography, art, workshops and writing at MattHillArt.com. Follow Matt on Twitter Instagram Facebook.

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4 Ways to Remove Airplanes from Star Stacks

When I make a star stack sequence, I’m at a crossroads for my editing choices.

Do I remove the plane trails? If so, do I live with the tiny gaps in those star trails left behind by the removal process?

It’s a hard decision. On the one hand, the journalistic approach is, “That’s what happened in front of my camera—it’s the truth.” If that’s your creed ... you’re done! Make whatever levels and color adjustments you want and move on.

But when I desire to have a final image without plane trails, I spend some time to make sure it’s done right, and that I’m making a quality photograph.

Want to learn some techniques on how to do this? Is there a method—without having to be a professional photo retoucher—that doesn’t leave gaps? Read on, my fellow night photographer.

Note:

If you are unfamiliar with how to create a star stack, see these previous blog posts:

Prep: How to Find Which Layers Have Plane Trails

I used the same image stack for all the demos below. Shot in the Fruita Orchard of Capitol Reef National Park during our workshop in June 2018.

Gear:

Exposure details:

  • 63 images shot at 30 seconds, f/5.6, ISO 6400
  • total exposure duration: 31.5 minutes

I knew I wasn’t going for star points, so I chose a 30-second exposure to keep long exposure noise down in the high desert summer heat. The temps weren’t that bad, but I wasn’t taking any chances.

For expediency, I exported full-resolution JPGs from Lightroom to Photoshop. Stacking TIFFs straight from Lightroom with this many files can really choke a computer. As it was, the PSB file was 4.2 GB when saved.

Note:

Do not apply lens profile corrections before making a star stack. It can lead to irreparable moire in the final stacked image. If you want to do apply lens corrections, do so after stacking and flattening.

How to Find the Planes

  1. Create your image stack in Photoshop and save as a PSD or PSB file (the latter when the file is over 2 GB—don’t worry, Photoshop will prompt you if it’s needed).
  2. Identify which layers have plane trails. But how, you ask?
  3. I like to turn on all the layers and apply the Lighten blend mode to each so I can see everything.
  4. Then I click and hold on the eyeball icon at left of each layer and drag downward in groups of ten or so, while staring at the image. This gives me kind of a faux animated preview of the layers being added one by one. (See video below.)
  5. If I see plane trail (or a portion of one) disappear, then I click the eyeball on each layer, one by one, upward from the bottom until it disappears. That’s how I know I found the offending layer.
  6. I make that layer a color to identify it for further work later.

An alternative way to do this is by revealing only one layer at a time, from top to bottom. Which strategy to use is just personal preference. Unless you’re on a PC, apparently. Chris is a PC user, and the trick I detail above and in the video doesn't work for him. What he does is group the layers ten or so at a time, changes the blend mode of all the groups to Lighten, then hides each group one by one, which helps him narrow down the locations of trails more quickly. Finally, he goes into the offending groups and finds the offending planes.

Either way, this process is time-consuming. So be patient. Find those planes. For the photo in the video below, the process above took me about five minutes. (I made it faster for you to watch.)

Note:

You may also find meteors and satellites in there. We have another blog post coming soon on how to identify the differences between them.

4 ways to remove plane trails in a star stack with Layer Masks

  1. Remove plane trails in a flattened image in Lightroom.
  2. Use the black paint brush in Photoshop.
  3. Use the spot healing brush in Photoshop.
  4. Use layer masks in Photoshop.

Which one is best? I am going to explore all four and compare them, so you can decide which works best for you. And, you can bet that I will have an opinion about what works best for me, too. ;-)

Removing Plane Trails in a Flattened Image

This is the fastest method, but also the least likely to be effective in terms of quality. If you must have it fast, try this first. If you don’t like the results, try one of the options that follows.

  1. Open your flattened image with plane trails in Lightroom.
  2. Select the Spot Healing Brush.
  3. Click once at the beginning of the trail. (See note below.)
  4. Hold Shift on your keyboard.
  5. Click once again at the end of the plane trail.
  6. Repeat for every plane trail on every layer.

NOTE:

You can paint freehand with the trackpad on your laptop (most awkward), with your mouse (somewhat awkward) or with a tablet like a Wacom (hardly awkward at all). This applies to subsequent techniques too.

I find that using keyboard arrow keys to move the healing brush target around is easier to manage than just using a mouse or trackpad. But it causes “jaggies” (below) more often than not, no matter how precise you are.

Using a Black Paint Brush in Photoshop

Since the Lighten blend mode for layers reveals the brightest pixels in a scene, painting with a black brush right on the image layer will make trails (which are bright) disappear.

  1. Select the Brush Tool with these settings: Opacity at 100 percent, Flow at 100 percent and Color at 100 percent black.
  2. Make your brush slightly larger than the width of your plane trail. (You may have to adjust this up and down, depending on the trail.)
  3. Paint over the plane trails. But only over the plane trails.
  4. Repeat for every plane trail on every layer.
  5. Merge layers or flatten when done with all.

Resulting image after using black brush to remove plane trails. Click to enlarge.

100 percent zoom crop to an area where a plane trail was removed.

In this video, I used the process of identifying layers first and then color-coding them before blacking out the trails. Even then, I discovered more along the way.

Note:

This is a destructive process. No going back. Unless you duplicate each layer you paint on and turn off the duplicate, but that increases your PSD/PSB size.

Using the Spot Healing Brush in Photoshop

I recently discovered this. While mucking about in Photoshop, editing my star stacks from Capitol Reef National Park earlier this year, I had a What If? moment. …

I asked myself, “What if I try using a different tool to remove star trails?” (I usually use layer masks, which we’ll get to in a little bit.)

  1. Select the Spot Healing Brush tool, and change the Type to Content-Aware.
  2. Make your brush slightly larger than the width of your plane trail.
  3. Click once at the beginning of the trail.
  4. Hold Shift on your keyboard.
  5. Click once again at the end of the plane trail.
  6. Repeat for every plane trail on every layer.
  7. Merge layers or flatten when done with all.

It works. I love this method, despite it being a destructive process.

Resulting image after using Spot Healing Brush to remove plane trails. Click to enlarge.

100 percent zoom crop to an area where a plane trail was removed.

In this video, I simply went from top to bottom to eliminate trails in each layer without color-coding them. I missed one plane trail, because I was kinda tired doing both back to back.

Note:

As mentioned, this is also a destructive process. No going back. Unless you duplicate each layer you paint on and turn off the duplicate, but that about doubles your PSD/PSB size.

Comparing the Methods

Let’s take a look at how the methods stack up against each other. (See what I did there?)

The edit in Lightroom of a completed, flattened stack? I immediately abandoned it. It was janky to complete, and undesirable:

And when your stars go the wrong way, it’s really hard to make it match:

So, all that’s left are the two competitors we’ve looked at so far. Below you can see the final images from each:

And here are some comparisons I made while viewing both simultaneously in Lightroom:

Above you can see that there isn’t really much difference between the two methods. At least in terms of image quality.

But … what did my time cost?

Painting Black

Pros: Easy to see if you covered a plane trail.

Using Spot Heal Brush

Pros: I just feel better seeing an image versus black lines all over. The trails are gone, and the layers still looks like a photograph.

Both methods have the same cons:

  • destructive to pixels
  • makes some gaps in the trails (thought remarkably few)
  • no way to go back on edits unless you duplicate your PSD/PSB beforehand

To Identify or not to Identify

I spent eight minutes identifying layers with stuff to eliminate.

I spent 30 minutes using the black brush on those layers I identified.

I spent 27 minutes using the Spot Healing Brush, layer by layer, without color-coding or pre-identifying layers.

It’s up to you which method helps you get through the process better. I can operate without color-coding in the future. One-by-one is the way for me.

Conclusion: Which Method Wins?

Guess what? Both strategies are just as effective. Yay!

And here is the proof: When gaps appear, they do so in the same places using both methods.

The above were from testing my own hypothesis that Spot Healing would work better. Surprise! I’m delighted to discover that for this test, both techniques performed the same.

Both methods create gaps. But you can meticulously fill them in with Photoshop prior to flattening. Use the clone tool, if you have the extra hours. ;-)

The Fourth Way—Using Layer Masks in Photoshop

This is how I’d always done it before my recent discovery. This method is non-destructive—if you save your PSD/PSB, you can always roll back the edits or modify them. (The downside, of course, is that an unflattened, many-layered file could be downright huge. If you’re not planning to save an unflattened file, this doesn’t provide much benefit.)

  1. Add a mask to a layer with a plane trail.
  2. Select the Paint Brush tool with these settings: Opacity at 100 percent, Flow at 100 percent and Color at 100 percent black.
  3. Make your brush slightly larger than the width of your plane trail.
  4. Click once at the beginning of the trail.
  5. Hold Shift on your keyboard.
  6. Click once again at the end of the plane trail.
  7. Repeat for every plane trail on every layer.
  8. Make your final contrast, color and other finish adjustments.

Give it a shot. You may like this better, especially if you are already masking out other things in your scene.

Et al.

Here are some examples of other stacks I’ve done using these techniques:

So go forth and capture, my fellow lovers of the night sky. And fear not the airplanes arcing across the heavens, for you can make their presence just a memory.

Matt Hill is a partner and workshop leader with National Parks at Night. See more about his photography, art, workshops and writing at MattHillArt.com. Follow Matt on Twitter Instagram Facebook.

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How I Got the Shot: Lake McDonald in Glacier National Park

Star Circles Over Lake McDonald. © 2015 Gabriel Biderman.

I’m fortunate to visit the Treasure State, Montana, at least once per year. But unfortunately it took me too many years to finally visit the Crown Jewel of Montana, Glacier National Park. There might not be as many glaciers as when the Great Northern Railway cut its path west over 100 years ago, but the three ranges of the Rocky Mountains still carve out some incredibly impressive views.

In 2015, before I saddled up on my motorcycle to ride out to Going to the Sun Road, I synced up with my good friend and fellow NPAN instructor Tim Cooper, who has been leading workshops in Glacier for more than 10 years. In fact, we are very excited to have him lead our first night ventures in Glacier in August and September.

I had only a couple of days to spend in the park, and Tim shared some of his favorite locations, which made the scouting so much easier.  Tim suggested we spend the night at Lake McDonald (below), as it has one of the iconic views in the park.

Scouting photo of Lake McDonald in  Glacier National Park .

Scouting photo of Lake McDonald in Glacier National Park.

The Location

Lake McDonald is definitely a popular spot, and it sits about 11 miles into the park on Going to the Sun Road. There are many cabins and campsites that let you take in all of this majestic beauty.

As I walked along the southern shore where most of the boat and kayak rentals are based, it became more and more obvious what kind of picture I needed to make. An epic location requires some epically long star trails! When we aim our camera to the northern skies we can create those jaw droppingly long circular star trails. In order to do this effectively, you need to dedicate at least 1.5 to 2 hours to shooting. So charge up your batteries and I’ll share with you how I got the shot!

Lake McDonald, my shoot location, is nestled along Going to the Sun Road on the west side of the park.

Lake McDonald, my shoot location, is nestled along Going to the Sun Road on the west side of the park.

The Conditions

The night I took this shot was June 6, 2015. The sun set at 8:35 p.m., but because we were at a higher latitude at the beginning of summer, the twilights lasted almost three hours. I guess I was lucky to actually get a night sky at all! The moon was a waning gibbous of 76 percent, but wouldn’t rise over the horizon until 11:44 p.m., meaning it wouldn’t rise above the mountains until at least an hour later.

Soon after the sky grew dark, I walked out onto the long dock to start shooting. As we entered astronomical twilight, which was to last over an hour, I was amazed to see the clarity of the northern tail of the Milky Way. I was joined by an astro-enthusiast who had his iPad out and was using a star map guide to identify all the celestial bodies that were shining brightly and surrounding us from all sides. It was so dark that the stars were easily reflecting in the calm waters of Lake MacDonald.

The Gear

The equipment I had with me presented a challenge for star-point photography. My lens was a superwide 10-24mm f/4 on the Fujifilm X-T1. The wide was good, as it let me get to a shutter speed of 30 seconds without stars starting to trail. However, we typically like “faster” lenses of f/2.8 or wider to let in more light and keep our ISOs somewhat manageable.

I had to work with what I had and shoot at ISO 6400 for 30 seconds at f/4. That resulted in definitely a noisy image, but I embraced the grain by converting this “bonus” shot (below) into black and white, and I’m very happy with it.

My first photo of the night, of the Milky Way floating over Lake McDonald and the distant mountain ranges. Fujifilm X-T1, 10-24mm f/4 lens. 30 seconds, f/4, ISO 6400.

The Shoot

I like nights that give you both complete darkness and moonlight to work with. This enables you to come away with a variety of night images as you explore the many different lights of night.

One thing I love about moonlight is how much color it brings into the night. Dark black skies can be difficult to work with, but a lick of moonlight brings a little blue to the sky.

I felt it was wise to move off the dock and onto more stable ground, to shoot from the terra firma along the beach. The moon was rising, and after taking a few test shots to finesse the composition, it was important for me to confirm that the North Star was still in the shot. It can be difficult to make out the exact placement of the North Star in an image, so before committing to a long exposure, I take a 2-minute shot so I can see how the stars are rotating (Figure 1). That confirms the placement of Polaris in the frame.

Figure 1. Test shot to confirm that Polaris is in the desired spot in the composition.

Figure 1. Test shot to confirm that Polaris is in the desired spot in the composition.

After I confirmed focus and composition, I settled on an exposure of 2 minutes, f/4, ISO 3200. I chose this setting because I was looking for the optimal image quality for star stacking and had noticed that the Fujifilm cameras quickly get color noise after 2 minutes of exposure at temperatures of 60 degrees or more. Also, Fujifilm caps their longest exposure in Bulb mode at 60 minutes, and I definitely wanted to blow past that!

I couldn’t have done such a long cumulative exposure without the help of the Tether Tools Case Relay. Typically mirrorless cameras can last about 1 to 1.5 hours of straight shooting on a fully charged battery. Tether Tools lets you plug one of their dummy batteries into your camera’s battery compartment and then link it to the Case Relay and a 10,000mAh USB battery to give you a much longer charge. (Check out the video we made that shows this in action.)

With the Case Relay hooked up, I set my Vello intervelometer to 2 minutes with a 1-second break between shots. I then lay back on the sand and enjoyed the show! I think I might have taken a little catnap during this shot, as the camera kept clicking for 1 hour and 24 minutes!

The Post-Production

I was very excited to see this shot. At that time it was my longest star trail to date. (My current mark is 6 hours ☺.)

The star stack was fairly easy to put together using Lightroom and Photoshop. In the Lightroom Library module I flagged all the “images to get stacked” (Figure 2) with a red color label (number 6 on your keyboard).

Figure 2.

This makes it easy to differentiate between my test shots and the images that have only a 1-second break in between. Once I had them marked, I selected them all and then clicked Photo > Edit In > Open as Layers in Photoshop (Figure 3).

Figure 3.

Depending on how many images you have and how powerful your computer is, this can take just a few minutes or enough time to brew and drink some coffee. Once the images loaded in Photoshop as layers, I selected them all. Then from the Blend Mode drop-down menu I chose Lighten (Figure 4).

Figure 4.

This blend mode lets the brightest part of each layer reveal itself in the final image. This connected all the bright star trails, as well as the car trails in the background (Figure 5).

Figure 5.

I saved the file, and Photoshop sent it back to Lightroom, where I did some basic touch-up to finalize the image (Figure 6).

Figure 6. Final image. 41 stacked frames, each shot at 2 minutes, f/4, ISO 3200.

Typically when you expose a night sky for this long, you are bound to get airplane or satellite light trails as well, but Glacier must be a very special place to have such a limited amount of “sky traffic.” I didn’t see any in my photo.

Final Thoughts

This is one of my favorite shots, still to this day. It heightens the majesty of Glacier National Park. I love how the moonlight reveals the Livingston and Lewis mountains ranges in the distance but also creates a mirror reflection. When I saw the cars come down Going to the Sun Road during my exposure I thought I’d have to remove them in post, but they slice through the shadow and its reflection perfectly. Oh, and who doesn’t like reflections of star trails? Yes, please!

This shot reconfirms the pristine beauty of our national parks at night. And aside from the gentleman with the iPad, I had Lake McDonald to myself that night!

Note: When we announced our 2018 night workshop at Glacier National Park, it was one of the first to sell out. We recently added a second week and we still have a few spots left. If you want to create images like this, come join us at the Crown Jewel of the Continent!

Gabriel Biderman is a partner and workshop leader with National Parks at Night. He is a Brooklyn-based fine art and travel photographer, and author of Night Photography: From Snapshots to Great Shots (Peachpit, 2014). During the daytime hours you'll often find Gabe at one of many photo events around the world working for B&H Photo’s road marketing team. See his portfolio and workshop lineup at www.ruinism.com.

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How I Got the Shot: Waterfall and Clements Mountain in Glacier National Park

“ Clements Mountain, Star Trails, Waterfall .”  ©  Tim Cooper.

Clements Mountain, Star Trails, Waterfall.” © Tim Cooper.

The Location

I am fortunate to live in Montana. It’s a beautiful state filled with wonderful people and fantastic landscapes. My “backyard” is Glacier National Park. Glacier is truly one of America’s great alpine experiences—from gorgeous glaciated peaks to alpine meadows carpeted with wildflowers to the host of wildlife visible on a near daily basis. I take every chance I can to get up to the park.

Early last summer I made this image while scouting for our upcoming National Parks at Night workshops in August and September. (While the first week of this workshop is already filled, the second week still has some spots available. Check out our workshop page for more information.)

Luck vs. Planning

When it comes to photography, I always give luck a little credit. Did the clouds cover the sky? Or did they add a nice accent? Did it rain on the night I had planned to shoot? There are so many small blessings that are easy to overlook.

Luck, however, is no substitute for planning. If you read this blog often then you have seen us discuss many times the importance of planning a night shoot. My familiarity with Glacier helped enormously with planning this shot. I already knew the location of the waterfall and exactly where I wanted the moon to be so that it would backlight the water. It was just a simple matter of using the indispensable phone app, PhotoPills, to determine when the moon would reach the necessary spot in the sky (see Figure 1).

Figure 1. The zoomed-out and zoomed-in views of the shoot location, as seen in PhotoPills’' Planner mode. The blue lines told me where the moon would be at different times of the night, which told me when to shoot for the effect I wanted.

The Exposure

I wanted to use the moon to illuminate the falls, but I also envisioned star trails rather than star points in my image. To create the effect of star trails, you have to make a very long exposure—15 minutes, 30 minutes, an hour or even longer. This makes the stars appear as if they are trailing through the sky. Another method to create these trails is to break up the exposure time into shorter chunks, and then stack the resulting set of images in post-production. This is especially helpful under bright moon situations or when you want to light paint.

Using multiple short exposures was my plan for this setup. The first step was to calculate an exposure using a high ISO test (i.e., the 6 Stop Rule). Setting my Nikon D4s to ISO 3200 and f/4, my final test shot (Figure 2) was exposed for 30 seconds.

Figure 2. Test shot at 30 seconds, f/4, ISO 3200.

The Shoot

Typically night photographers use an ISO of 6400 for test shots because, according to that 6 Stop Rule, we know that an exposure time of X seconds at ISO 6400 equals X minutes at ISO 100. This is a very handy little trick for calculating long exposures easily.

Because my successful test exposure was 30 seconds at ISO 3200, which equals 15 seconds at ISO 6400, then my long low-ISO exposure would be 15 minutes at ISO 100. Or—to shorten things up a bit—8 minutes at ISO 200. Using this exposure, I could shoot multiple frames at 8 minutes and blend them later in post using the star-stacking technique.

This evening, however, I either miscalculated or mistakenly set my camera wrong. My final exposures (Figure 3) ended up being shot at 5 minutes, f/4, ISO 100. That’s about two stops underexposed!

Figure 3.

I didn’t notice that at the time. I finished shooting and had to leave immediately, so there was no time to reshoot the frames. I was destined to have to fix it later in post.

Post-Processing

After downloading my images, the first post-processing edit was adjusting the Exposure slider to account for the underexposure out in the field. After increasing the exposure, the final set of images looked like this:

Figure 4.

The next step was to blend all the frames together to create the star trail effect. I began by selecting all of the images in Lightroom. Next, from the menu I selected Photo > Edit In > Open as Layers in Photoshop. This opens all of the images into Photoshop as layers within one file.

Once the file opened, I clicked on the top layer, held down the Shift key, then clicked on the bottom layer. This selects all of the layers in the file.

Next, in the Blending Mode drop-down list (circled in red in Figure 5), I selected Lighten (Figure 6).

Figure 5.

Figure 6.

This blending mode allows the brightest part of each layer to show through on the final image, which in this case creates the effect of the stars trailing across the sky. Figure 7 shows the result of blending the images with this technique.

Figure 7.

Did you notice the multiple car headlights that showed up after blending the layers? They were in the first, second and last photo frames (Figure 8). Because using the Lighten mode reveals the brightest parts of each layer, all the headlights showed up after blending.

Figure 8.

So, the next step was to remove the unwanted car lights. One of the benefits of stacking frames rather than taking one long exposure is that you can use layer masks to remove unwanted artifacts that show up in just a few frames rather than overwhelming an entire final photo. To do this, I clicked on the first layer that contained headlights to select it. Then at the bottom of the Layers palette I clicked on the Add a Mask icon (Figure 9).

Figure 9.

Figure 10.

Next I selected the paintbrush tool and chose black as my foreground color. Then I just painted on the mask over the area I wanted to remove. Notice in Figure 10 how I painted over the tunnel where the car headlights appeared. Also notice the corresponding black area on the white mask thumbnail, indicating the shape and location of the mask.

I followed the same steps for the other two layers with the artifact, painting out the headlights further up the road. Figure 11 shows the three masks with black painted on them covering up all of the headlights that exist on the different layers.

Figure 11.

Figure 12.

Finally, I wanted to separate the cool tones of the sky from the foreground waterfall. I clicked on the bottom layer, chose the Quick Select tool and then selected the foreground waterfall and cliff face (Figure 12).

Then I created a Color Balance layer by choosing Layer > New Adjustment Layer > Color Balance. Adding some warmth via the Red and Yellow sliders started to really separate the warm colors in the foreground from the cool colors of the background.

Figure 13 shows the final image.

Figure 13. Five stacked frames, each shot at 5 minutes, f/4, ISO 100 with a Nikon D4s and Nikkor 14-24mm f/2.8 lens zoomed out to 14mm.

While this may sound like a lot of work, after a little practice in Photoshop, you’ll find that completing these types of images takes no time at all!

Tim Cooper is a partner and workshop leader with National Parks at Night. Learn more techniques from his book The Magic of Light Painting, available from Peachpit.

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How I Got The Shot: Star Stacks and Sea Stacks in Olympic National Park

Sea Stack at Ruby Beach, Olympic National Park. Nikon D3s, Nikkor 17-35mm f/2.8. 120 stacked exposures shot at 20 seconds, f/2.8, ISO 1600. Light-painted with a Coast HP7R flashlight. © 2016 Chris Nicholson.

The Location

It’s hard for me to choose a “favorite” national park, because it’s like trying pick a favorite item from a buffet of candy and ice creams. But Olympic National Park would certainly be near be near the tippy-top of my list, if not the cherry at the very top.

Not only is Olympic simply beautiful, but its three distinct ecosystems—mountain, rain forest and coast—all present unique photography opportunities. You could literally be shooting an entirely different scene and genre from one hour to the next.

My favorite of those ecosystems? That’s an easier question to answer: the coast. I grew up in New England only a mile from the shore, so my affinity for the water is strong. And my favorite spot on the Olympic coast to photograph? Ruby Beach.

Ruby Beach is a stunning stretch of coastline ... flanked by high cliffs, lined with hundreds of ancient, massive driftwood logs, divided by Cedar Creek, and punctuated by picturesque sea stacks amid the crashing Pacific waves.

During my four visits and shoots at Olympic National Park, I’ve shot at Ruby Beach in three of them. When I visit the park again this September to prepare for the two workshops we’re hosting there, I’m certain to shoot at Ruby again.

Ruby Beach is a stunning stretch of coastline that is a perfect location for photographing sunsets, in sunset light, on overcast days (tide pools!) and, of course, at night. The shore is flanked by high cliffs, lined with hundreds of ancient, massive driftwood logs, divided by Cedar Creek, and punctuated by picturesque sea stacks amid the crashing Pacific waves.

(Shameless plug: I’d be happy to personally show you around Ruby Beach this September, when Matt Hill and I run our two workshops there. A couple of seats are still open for each week—September 17 to 22 and September 24 to 29—so sign up today!)

Here are a few of photos to give a sense of what Ruby Beach looks and feels like:

The Setup

On a July afternoon in 2016 I scouted Ruby Beach for a night shoot, and planned three setups for once the sky grew dark. I knew I would have a good view of the Milky Way, and intended to frame it with sea stacks in two of the setups, but also wanted to rip one long exposure to capture some southern star trails.

One thing I kept in mind while scouting is something that can be important when working around the coast: Changing tides affect the appearance of the shoreline. To get a good idea of what the water levels would look like once shooting at night, I used the Tide Graph Pro app. I looked up the tide chart for that date (see Figure 1), noticed where the water level would be during my nighttime shoot (about 9 pm. to 1 a.m.), found a corresponding tide level during daylight (about 1 p.m.), and visited at that time for scouting. This way I didn’t have to imagine what the water would look like later—I knew exactly.

Figure 1. Tide Graph Pro showed me that the tide level during my shoot would be at about 1 foot above the zero tide height. I saw that the water would be at about 1 foot also around 1 p.m., so that is when I did my daytime scouting.

Incidentally, knowing the tides is important for safety too, especially in Olympic National Park, where many headlands are impassable at high tide. You don’t want to venture around a promontory at low tide and get trapped a few hours later when the water floods your trail back.

The Gear

Ruby Beach is certainly not a long hike from the car—it’s only about a half-mile round-trip—but because I was working on a beach, I didn’t want to be burdened with a heavy bag that I’d be tempted to put down in the sand during my several planned hours out. So I left some of my gear in the car and brought along a one-camera, two-lens, one-tripod kit:

The Exposure

For the star trail photo, I chose a single sea stack about halfway between Cedar Creek and Abbey Island, and once set up I started to “work the scene”—i.e., I shot from several different angles, some without light painting, some with varying approaches to light painting, some including the Milky Way, some including reflections in the sand as the tide receded. You can see a couple of the variations in Figures 2 and 3.

Figure 2. My first composition included the reflection in the wet sand, which is how I visualized the photo during my daytime scouting, an approach I abandoned while adjusting the composition.

Figure 3. My second attempt at a composition included a little of the Milky Way to the left. I also tried scraping the wet, pebbly shore with some light painting to emphasize the texture of the wavy sand.

I ultimately chose an angle that allowed me to get a little of the Milky Way behind the sea stack. I didn’t like the position of the galactic core in the frame, but figured that as it moved over the next hour or so, it would eventually be in a spot I did like. This led me to a key decision in how I approached the exposure: I chose to create my star trails using a long series of short exposures that I would later stack in post-production.

I could have created the star trails using one very long exposure, but there are drawbacks to that approach, including a significant drain on the camera battery, along with the introduction of long-exposure noise, which would be particularly problematic in warm midsummer temperatures. So instead I opted for “star stacking.” Star stacking is a post-processing technique for creating star trails that solves many of the image-quality issues inherent in night photography. (I will likely write more about all of that in a future blog post, so please stayed tuned for a year or two.)

Star stacking involves shooting multiple frames of the scene that are later layered together in Photoshop in a way that combines the stars into the same trails they would have made in a long exposure. You can do this with shutter speeds of any length. For example, if you wanted to create one-hour star trails, you could star-stack 12 5-minute exposures, or 30 2-minute exposures, or 60 1-minutes exposures, or so on.

Star stacking is a post-processing technique for creating star trails that solves many of the image-quality issues inherent in night photography.

For this photo, I shot 120 20-second exposures, giving me the equivalent of 40 minutes of star trails. Shooting that many frames meant I’d have more work to do later in Lightroom and Photoshop, but there was a reason I chose this approach, and it goes back to the decision about the Milky Way. I wanted to be able to pick out of my sequence one frame in which I liked the position of the galactic core, and I wanted that frame to have crisp star points.

I had my lens zoomed to 19mm, and using the 400 Rule, I knew that my shutter speed could be no longer than 20 seconds before the stars would start to blur. Therefore, I set my shutter speed to 20 seconds, and calculated that I would need 120 frames to produce my 40-minute star trails.

I set my aperture to f/2.8, and I used hyperfocal distance to ensure that both the sea stack and the stars would be in focus. I set the ISO to 1600, which could normally be quite low for star points, except that the moon was close to rising—not close enough for its light to be seen by the naked eye, but close enough to brighten the sky a bit during a long exposure. Shooting at f/2.8, I would have plenty of stars to trail, so I wasn’t concerned about them being a little dim, and because I would be light painting the sea stack, I wasn’t concerned about lacking shadow detail.

The last piece of the puzzle was the light painting. The sea stack was too prominent in the frame to use as a silhouette—half the composition would have been pure black. So I wanted to light paint the rock in a way that would bring out its texture and color. I experimented with different angles and determined the best option was lighting from the right, standing as close to a 90-degree angle to the sea stack as I could without stepping into the waves. (See Figure 4.)

Figure 4. A self-portrait of me light painting the sea stack.

I also experimented with different flashlights and chose my Coast HP7R, because its wide, crisp edge-to-edge beam allowed me to evenly paint the entire sea stack from a relatively close distance without having to move the light. Figure 5 is the painting approach I settled on.

Figure 5. The final approach to the light painting, after trying several variations.

The Shoot

Once my exposure and light painting strategies were set, all I needed to do was execute the sequence. Because I was shooting 20-second exposures, I didn’t need an intervalometer, so I simplified matters by using a wired remote shutter release that I could lock (specifically, the Nikon MC-30A). The camera was set in Continuous shooting mode, so all I needed to do was push the button on the remote, set the lock, and let the camera do its thing 120 times.

During the first exposure, I did the light painting that I had already practiced. The remaining 119 frames have just a silhouetted sea stack. I went for a walk and enjoyed a quiet night on the coast under the dark skies of Olympic National Park.

Figure 6. The entire 120-frame sequence in Lightroom.

The Post-Production

The star-stack process is actually pretty simple for such a powerful technique.

After dumping the cards into Lightroom, I looked at the images and decided not to make any adjustments other than adding a standard touch of Vibrance and Clarity, and (this is important) in the Len Corrections panel I turned on Remove Chromatic Aberration and Enable Profile Corrections. I made those adjustments to one file, then selected the entire sequence and clicked the Sync button to apply those changes to all the highlighted files.

With the entire sequence still selected, I went to the menu and chose Photo – Edit In – Open as Layers in Photoshop. This maneuver created a new file by making a layer out of each of the selected frames of the sequence I had shot on the beach. (See Figure 7.) Because I initiated this process for over a gigabyte of collective data, once the computer was working I went to the kitchen and made a sandwich and a cup of coffee. My computer is no slouch, but it still needed a good 20 minutes to complete the job.

Figure 7. Each frame of the sequence was imported to Photoshop as individuals layers in one file.

The next step was to select all the layers (Figure 8), which can be done either by shift-clicking the first and last layers, or by pressing Control+Option+A (Mac) or Control+Alt+A (PC).

Figure 8. All layers selected.

Then, using the drop-down menu at the top of the Layers panel, I changed the blend mode to “Lighten.” (Figure 9.) The Lighten mode essentially looks at the layers as a pile of aligned images, searching through each of them pixel by pixel. It searches for the lightest pixel in each pixel pile, then brings that lightest pixel to the top. In the case of stars that are moving against a dark sky, that means the star point in each layer is brought forward, thus creating the trails. (Note to astronomers: Of course we know that it’s actually the Earth moving, not the stars, but it’s easier to explain this way, so please bear with me.)

Also, because I light-painted the sea stack in that one frame but left it silhouetted in the others, the sea stack is also brought forward. No masking needed—it happens automatically.

Figure 9.

That’s a sort-of technical explanation of how the Lighten mode works behind the scenes. What I see on-screen is some nifty magic of star trails appearing where before there were only star points and dark sky. (See Figure 10.) It looks pretty much the same as if I’d shot the 40-minute exposure, except it has no long exposure noise, and my camera battery didn’t have the life sucked out of it.

The Cleanup

The keen observer will note that while shooting those 120 frames, some planes flew through my composition, and they impolitely neglected to turn their lights off before doing so. Some photographers like to keep plane trails in their photos. I’m not one of those photographers. Getting rid of them is a simple matter of masking or cloning them out of the layers they appear in.

I also wasn’t crazy about the bright star trail in the upper right corner of the composition. It’s the brightest and thickest trail, and it’s right in the corner, where it draws attention far away from where I want attention drawn. So I masked it out.

One more bit of cleanup I did was in the lower right corner of the composition, where you can see a big blotch of light that was caused by a moving star being distorted in the reflections on the sand. That was relatively easy to mask out as well.

Figure 10. The artifacts from stacking that I masked out of the layers in Photoshop.

Figure 10. The artifacts from stacking that I masked out of the layers in Photoshop.

The Save

The final decision in creating a star stack is whether to save the layered PSD file. If I had shot the sequence using fewer longer exposures (for example, eight 5-minute exposures), then saving the layers file may have been feasible, and it would have come with the benefit of being able to make adjustments to the individual layers in the future. But I didn’t do that—I used 120 short exposures to create this stack, and if I saved that as a PSD—well, I wouldn’t be able to, because it would have resulted in an 8 GB file, which is too gigantic for the PSD format.

Rather, I would have had to save it as a PSB, which is Adobe’s large document format. But I still would have ended up with a giant file that I don’t want to deal with reserving space for or having to open again. So instead, I flattened the image and saved it as a 70 MB PSD, which while not as flexible for future edits, is much easier to maintain. Should I ever want to approach this image differently, I can always recreate it from the sequence files—and enjoy another sandwich and cup of coffee while doing so.

Once the star-stacked photo was saved and back in the Lightroom catalog, I made some minor adjustments to Clarity and Vibrance to optimize the look of the stars, and that was that—star trails over Ruby Beach.

Figure 11. The final image.

And what about that star-point Milky Way photo I wanted to pull out of the sequence? Well, I didn’t like the position of our galaxy in any of those 120 frames. So after I wrapped the star stack sequence, I reframed my composition and shot Figure 12 instead.

Figure 12. The Milky Way over Ruby Beach in Olympic National Park. © 2016 Chris Nicholson.

Speaking of the Milky Way, can you see it in the star trail photo (Figure 11)? It’s to the left of the sea stack, and you can discern it by the telltale cluster of denser star trails. It looks like a streaky cloud of light. That’s what our galaxy looks like in a long exposure!

Note: If you’re interested in joining NPAN instructors Chris Nicholson and Matt Hill in Olympic National Park, there are only a few spots left, so sign up today! We’re offering two weeks in this amazing national park: September 17 to 22 and September 24 to 29.

Chris Nicholson is a partner and workshop leader with National Parks at Night, and author of Photographing National Parks (Sidelight Books, 2015). Learn more about national parks as photography destinations, subscribe to Chris' free e-newsletter, and more at www.PhotographingNationalParks.com.

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