Pentax

Five Questions: Flashlight Filters, Night Photography with Film, Adobe Bridge and More

We like getting questions. Sometimes they challenge us, sometimes they fascinate us, and sometimes they allow us to fill in the gaps of the things we teach on workshops and in our blog.

This installment of our “Five Questions” series features inquiries about making custom filters for color-correcting flashlights, Pentax’s built-in equatorial tracking, film photography at night, Viltrox lenses and using Adobe Bridge with Lightroom.

If you have any questions you would like to throw our way, please 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. Making Custom Color-Correction Filters

Coast Portland LF100 flashlight filters.

Q: Thanks for your recent post on color temperature. Can you describe how you physically make a filter for the flashlight? Tons of gaffer tape? — Will

A: You could use gaffer tape, or you could just wrap the gel around the end of the flashlight and hold it there with your hand or a rubber band. But there’s a more elegant way. In Part I of that series, Tim told how he attaches the gel to the flashlight. Personally, I like to use double-sided tape to adhere the gel to the clear filter, which gives me a nice, clean piece of gear to work with.

However, the first time I did this, I used standard-size clear tape. It didn’t fit across the whole filter, so I needed to use three pieces side-by-side, which created shadow lines in my flashlight beam. Not a huge problem, but it wasn’t polished enough for me. Moreover, one of the reasons I love using a Coast HP7R to light paint is because the illumination is even across the whole beam. So, shadows from my filter wouldn’t do.

Because of that, I instead started using clear mounting sheets. They come in 8.5x11 sheets, from which I can cut a piece that covers the whole filter. I cut a square piece large enough to cover the clear plastic disc, then use sharp scissors to trim the edges to align with the circle. Then I peel off the backing, adhere a square of filter gel, and finish by trimming that as well. If I need two gels, I repeat the process on the other side of the disc.

Then I can pop my custom filter in the holder, and light paint with precise color with no fuss. — Chris

2. Equatorial Tracking with Pentax

Q: I rarely see anything about the use of equatorial mounts in general, or more specifically what Pentax claims to have with their K1 being able to simulate an equatorial mount for up to 3 minutes. I purchased the K1 thinking that this was the way to go, but as I am just starting in astro-landscape photography, I would be interested in your thoughts on these approaches to letting the shutter stay open a little while longer. — Ray B.

A: None of us have shot with a Pentax K1, but I have a couple of friends who have, and the AstroTracer feature does indeed perform as advertised. Since you already have the camera, I definitely recommend that you give it a go. Just bear in mind that you will still have to do a separate shot for the landscape or foreground, as it will be blurred in the tracer image. (The AstroTracer tracks the sky, so the camera will not be synchronous with the earth!)

For general astro-landscape photography, typical exposures are 20 seconds, f/2.8, ISO 6400. With the AstroTracer, you should be able to get 2 or 3 minutes at f/2.8 to f/3.5 and ISO 1600, depending on your lens.

We would love to see your results. Please send us a couple of images, or better yet, share on our Facebook page. — Lance

3. Film Photography at Night

Q: Greetings from Portugal! I make landscape photos with long exposures, including night photography. I shoot in black and white with digital, but also with film (Tri-X), and recently I got some Acros. What are your views about these two options? — Verissimo

Figure 1. Click to englarge.

A: Thank you for reaching out, all the way from Portugal! I’ve used film for night photography for over 20 years—less and less over the last 2 or 3, but lately I’ve been resurging. (Keep your eye out for a post about that soon!)

Figure 1 is an excerpt from my book Night Photography: From Snapshots to Great Shots, with a chart that compares the film reciprocity of Tri-X and Acros.

As you can see, Tri-X is not a good film for night photography, unless you want to be pushed to very long exposures very quickly. A 15-minute exposure for digital would need to be doubled for Acros (30 minutes), but quadrupled for Tri-X. That’s 1 hour, and anything over 15 minutes is not recommended for Tri-X. This means that with Tri-X at night, you can shoot only under full moon or in brightly lit urban conditions.

Last summer there was some very good news for film night photographers, as Fujifilm brought back Acros after a yearlong hiatus. One of our most beloved black-and-white films, Acros has very low reciprocity failure and can be used successfully under a variety of low-light conditions.

Another thing to consider is that when shooting film at night you are technically overexposing the lights to get a better burn into the silver. To compensate, I advise that you reduce your development times by 10 percent or so to get the best results. Use my chart and -10 percent as a starting point to cook up solutions that best fit your style and the chemicals you use. — Gabe

4. Viltrox 20mm

Q: In your recent blog post “How to Plan, Shoot and Edit a Milky Way Arch Panorama,” I have to say I am a bit confused by this statement: “Lately I’ve fallen in love with the Viltrox 20mm f/1.8, because it comes in a Nikon Z-mount and is crazy-easy to focus manually.” I am unable to find this lens in a non-Z-mount. Maybe you can point me in the right direction? Also, do you know how the Viltrox compares to the Nikon F-mount 20mm f/1.8G combined with the FTZ Adapter? — Eunice

The Viltrox 20mm f/1.8 Z-mount lens.

A: Viltrox is a relative newcomer to the lens market. They presently make the 20mm f/1.8 lens only in a Sony E-mount and a Nikon Z-mount. The latter is not yet available through U.S. retailers, but you can order one directly through Viltrox on Amazon. The Viltrox website is not so up-to-date, but here is some information about the two focal lengths they make (20mm and 85mm). For most of what they manufacture that is available in the U.S., check out B&H Photo.

As for your other question, I have not compared those two lenses directly, so I cannot comment about the optics. But I can comment on the physical attributes.

The Nikon 20mm f/1.8G is substantially lighter, but then you do need to factor in the FTZ Adapter, which adds a little weight. The 20mm is very sharp, though it does suffer from more coma than the Nikon 14-24mm f/2.8, which is why the latter is legendary among night photographers.

Here’s the breakdown:

  • Viltrox: heavier, manual focus only, has coma until stopped down to at least f/2.8, all metal lens barrel, comes with adapter to use screw-on filters 

  • Nikon: lighter, requires adapter, auto and manual focus, also has coma until stopped down to at least f/2.8, plastic lens housing, can use screw-on filters natively

Matt

5. Bridge to Lightroom?

Adobe Bridge—meant for using with Photoshop, not generally with Lightroom.

Q: At a recent workshop you said not to use Adobe Bridge to edit photos before importing them into Lightroom, but rather use just Lightroom. If you import from Bridge, that changes the equation somewhat? Most folks in my camera club swear by Bridge. — Brien R.

A: If someone is not using Lightroom, then by all means they should be using Bridge. But there just isn’t any good reason I can think of to use Bridge before Lightroom. Everything that Bridge does is something that’s built into Lightroom, so using Bridge beforehand is just adding extra steps to accomplish the same tasks.

I’m not claiming that there’s not some truly efficacious reason out there to use Bridge first, but it would be a major exception to the rule, something that would fit a very specific, out-of-the-ordinary need. As an indication of how unusual that need would be, know that between Lance, Tim and I, we don’t know any professional photographer who uses Bridge before Lightroom. — Chris

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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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