National Parks at Night

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Five Questions: Meteor Showers, Pano Stitching, and Lots and Lots of Gear

Welcome again to the National Parks at Night Q&A, where we share some of the great questions we’ve received via email. This time around we're featuring Q’s and A’s about post-producing meteor shower photos, advice about five different camera systems, pano vignetting and wide-angle lens choice from the Nikon world.

If you have any questions you would would like to throw our way, contact us anytime! Questions could be about gear, national parks or other photo locations, post-processing techniques, field etiquette, or anything else related to night photography. #SeizeTheNight!

1. Meteor Showers Post-Production

Great Sand Dunes National Park, Colorado. Nikon D750, 15mm Zeiss Distagon f/2.8 lens. 234 images at 22 seconds, f/2.8, ISO 6400, plus a single exposure at 382 seconds, ISO 2000 for the landscape after moonrise. Photo © 2017 Matt Hill.

Q: Regarding your recent blog post “Meteors and Eclipses and Comets, Oh My!—The Celestial Events of 2018,” one of the spectacular photos that has me asking “How did he do that?” the loudest is Matt’s photo of the meteor shower in Great Sand Dunes National Park.

As a novice to post-processing, I can only assume that the 234 photos were somehow aligned so that the stars did not turn into trails, while ignoring the meteor shower streaks that were not in the all of the other frames, and then overlaying or merging in the foreground. Is that an oversimplification? — Rex

A: We are planning an in-depth post about this exact technique that will run this summer. But I’m happy to give you a light preview that should answer your question. The heart of the technique is this:

I used PhotoPills to scout the shot. It was also my fourth visit to Great Sand Dunes, and my second during the Pereid Meteor Shower (the first time I totally botched it!). This time I approached it with better planning (and with better physical conditioning—those dunes are difficult to climb!). From PhotoPills, I knew that astronomical twilight ended at a certain time and the moon rose at a certain time. The latter was important because I knew that the dunes just don’t look right without a little sidelight.

I set up my shot, started the sequence of exposures and waited patiently for moonrise. Others in our group who didn’t wait for the moon to side-light the landscape have radically different foregrounds in their final images, with less detail and muddy shadows. But I understand their hesitance to stay out so late; honestly, I would have light painted the dunes instead if the descent and subsequent ascent wasn’t so difficult. Besides, I was enjoying the show—lots of meteors all over the sky that evening.

When it came to post-processing, I was deeply inspired by David Kingham’s generous video from a few years ago. An even better explanation that you can hold in your hand is available courtesy of my National Parks at Night colleague Lance Keimig, who has a full description of the technique in his book Night Photography and Light Painting—Finding Your Way in the Dark (on pages 114 to 119).

I used a very similar technique to isolate the meteors with layer masking in Photoshop, and rotated those layers to align with the stars in the base image layer. (Another option is to use Starry Landscape Stacker.) I then layered in that moonlit foreground, performed some minor tweaking, and voila!

(You can also see my sequence of images rendered as a time-lapse on our Instagram account.)

So, in short, your guess about the technique is in part not oversimplified, but in part is. Watching the video, reading Lance’s book and waiting for our summer blog post will all help to clarify this in-some-ways simple yet in-some-ways complex technique that is, either way, tremendously rewarding.

Also, we are planning a one-night event during the Perseids this year—to be announced. Stay tuned for details! — Matt

2. Full-frame Camera for Milky Way Photography

Q: In one of your blog posts (by Lance Keimig, I believe), a comment was made about full-frame cameras being best for star and/or Milky Way photos. In the same post it was mentioned that most of the newer full-frame cameras should be able to handle ISOs in the 3200 to 6400 range. My question is: How new?

I am looking to upgrade from a crop-sensor to a full-frame DSLR in the Nikon series. The D810 is way out of my price range, but I am thinking about the D610, or possibly the D750 if I can get a great deal on a used model. Would the D610, which entered the market in 2013, handle the 3200 to 6400 ISO range well, or should I really focus on trying to find a D750 in my price range? — Larry G.

A: I would strongly recommend going for the D750. It is without a doubt the best value in DSLRs for night and astro-landscape photography. If you want a minimal kit, consider adding a Tamron 15-30mm f/2.8 lens, and that will be pretty much all you need, provided that you already have a decent tripod. The D610 is OK, but the D750 is stellar! — Lance

3. Pano Vignetting

Milky Way pano over Montana. Seven stitched images shot at 30 seconds, f/4, ISO 6400. Nikon D750 with Nikkor 14-24mm f/2.8 lens at 14mm. Photo © Gabriel Biderman.

Q: In shooting panos of the Milky Way and sunrises, etc., I’m having vignetting issues in Lightroom. When stitching, it creates vertical darker areas at the overlap portions of pano. Do you guys use third-party software to make night panos, or do you use Lightroom and Photoshop? — Steve W.

A: We are big fans of panorama night photography, but it definitely has its challenges.

While I have not noticed a heavy vignette in any of my panos, you might want to make sure you are applying your lens corrections prior to stitching. We generally work on all the individual images and correct them before stitching in Lightroom. Wider lenses definitely vignette more, especially when shooting wide open.

Lightroom and Photoshop do a pretty good job at single-row panos, but they can struggle with double-row and low-contrast scenes. I’ve just started playing with Autoan, which lets you take more manual control over your stitching. We will definitely be bringing this topic to our blog in the next few months as we do more testing and stitching! — Gabe

4. Canon, Phase One, Sony Options for Night Photography

Q: In building a kit for astro-landscape photography, do you know about the results from the Canon 5D as well as the 50-megapixel Canon camera? How about the Phase One IQ3 100-megapixel system? I have also heard the Sony system is great for astro-landscape images. — Jeannine H.

A: For astro-landscape photography, the best Canon cameras would be, in order of preference:

The 5DS and 5DS R are not built for high ISO or high dynamic range imaging, and as such are not well-suited for astro-landscape photography.

In terms of value, the 6D will by far get you the most for your money, but it is also an older camera that should be replaced soon. The next best value would be the 5D Mark IV. The minimal quality gain from the 1D X is not worth the extra money or weight in your bag. If you were stuck on Canon, I’d go for the 5D Mark IV.

As for the Phase One, in general, I have not been impressed by the high ISO performance of any of the medium format cameras, and the return on investment is definitely not there for night photography.

Regarding Sony, the a7S II and a7R II perform very well in low light and at high ISOs, and the live view in low light is great. However, I find the menu navigation is so awkward that it makes the cameras burdensome to use. (But it should be noted that learning menu structures from brand to brand tends to be like learning a language—the first you learn is the easiest, and everything after seems foreign.)

At National Parks at Night, most of us use the Nikon D750 at least part-time, if not full-time. It’s a great all-around camera, and a great value. The D750 and D850 outperform all of the Canons.

Another viable option you didn’t ask about is Pentax. The Pentax K1 combined with the 15-30mm f/2.8 lens is an outstanding value and is excellent for night photography. — Lance

5. Nikon Wides vs. Wide Zoom

Q: What is the advantage of the Nikon 14-24mm f/2.8 at $1,900 versus, say, their 24mm f/1.4 at about the same price? There’s more flexibility with the zoom, of course, but the f/1.4 is two full f-stops better. In night shooting, I guess that is really significant. But can’t you just increase the exposure time (leaving ISO alone) to compensate for the slower lens and obtain the same result? It seems the 14-24mm would be more useful presuming that f/2.8 will get the shot. Also, is there much difference in f/1.4 (24mm) versus f/1.8 (20mm) besides $1,200? — B.R.

A: Lots to consider here! But first, allow me to point out a misconception in your premise: You can’t just increase the exposure time and get the same results. Why? Because stars move. A 15-second exposure at f/1.4 would become (while leaving ISO alone, as you indicated) a 1-minute exposure at f/2.8; the former would likely produce sharp star points, while the latter would produce short star trails.

Now, on to the crux of your question: Why would we choose the slower 14-24mm over the faster 24mm f/1.4 or 20mm f/1.8?

Rocky Mountain National Park, Colorado. Nikon D810 and 14-24mm f/2.8. 15 seconds, f/2.8, ISO 6400. Photo © 2017 Chris Nicholson.

Yes, a wider aperture will allow you to expose with a faster shutter speed, which is important if you want to shoot a sharp Milky Way or star points, rather than longer exposures that create star trails. For example, say we’re shooting at a focal length of 20mm on a standard-size full-frame camera. Using the relatively accurate 400 Rule, we’d know that our maximum shutter speed for keeping the stars as points is 20 seconds. With that shutter speed on a new-moon night, at f/2.8 we’d need to shoot at about ISO 6400 to get a correct exposure. Whereas if you could shoot at f/1.8—an aperture 1 1/3 two stops wider—you could use ISO 2500, resulting in less high ISO noise in the image. Shooting at f/1.4 would be even better, because you could get the same exposure at ISO 1600.

That makes it sound like we should always use the widest aperture (and thus the fastest lens) possible. The caveat, though, is that not all lenses are created equal. For our purposes, there are two main points to consider:

  • Many lenses are sharpest (in terms of focus) with the aperture closed down a couple of stops.

  • All lenses suffer from some degree of comatic aberration, otherwise known as "coma." This aberration can cause stars—particularly those in the corners of the frame—to appear distorted, looking like tiny comets or flying saucers when viewed at 100 percent.

That brings us back to your question about why we might recommend the Nikon 14-24mm over the 24mm f/1.4 or the 20mm f/1.8. The reason is because from our experience with those latter two lenses, they show very apparent coma when shot wide open; with both, you need to stop down to about f/2.8 to get the coma to a level we believe is acceptable by our image quality standards. However, the 14-24mm produces so little coma that you can shoot it wide open and get the same results.

So, if you’d need to shoot those faster primes at f/2.8 anyway in order to get the same results as shooting the 14-24mm at f/2.8, then to us it makes sense to just use this fantastic wide-angle zoom instead and get the additional benefits of the variable focal lengths. — Chris

Do you have a question the NPAN team might able to answer? Email us today!

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.

UPCOMING WORKSHOPS FROM NATIONAL PARKS AT NIGHT

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