Friday, September 12, 2014

Gateway to Wall Street by Wayne Pinkston

"Gateway" to Wall Street, on the Navajo Loop Trail, in Bryce Canyon N.P. ~ © John Wayne Pinkston
Canon 6D, 15mm Sigma fisheye f/2.8, 30 sec. @ f/2.8, ISO 6400 — with light painting
"Seeking the Light", descending into Wall Street, Navajo Loop Trail, in Bryce Canyon N.P. ~ © John Wayne Pinkston
Canon 6D, 15mm Sigma fisheye f/2.8, 30 sec. @ f/2.8, ISO 6400 — with light painting (click to enlarge)
John Wayne Pinkston, or "Wayne", as he is known by his friends, recently made these photos in the early morning hours (about 2:00 AM) on August 30th, during a solo hike down Bryce Canyon's narrow "Wall Street", on the Navajo Loop Trail. Wayne had just finished one of my NightScape workshops in Bryce, and was anxious to put some of his knowledge to work.

Tools and Equipment: Wayne had already come prepared with several of the lights I recommend, along with some of his own improvisations. The "Gateway" arch was lighted from behind with an F&V Z96 LED Panel Light (with warming filter), and the canyon walls were lit with reflected light from a hand held Harbor Freight, Luminar Work, quartz halogen spotlight. To control stray light from his spotlight, Wayne used a rolled up plastic dinner placemat as a snoot! Even with the dimmer control at the Z96's lowest setting, the LED light was too bright coming through the arched tunnel, and Wayne again had to improvise.

"Subway napkins work really well. I had a pocket full of them. I wrapped two or three napkins around the light because it was too bright, and that worked well," quipped Wayne.

For "Seeking the Light", Wayne used two F&V Z96 LED's and a Chromo Inc. LED CI-160 (another dimmable panel light) spaced along the trail. All had their warming filters and diffusion attached, but he had to use an additional theatrical gel sheet on the CI-160 to make it match the two Z96's. (Editor's Note: a larger version of the CI-160, with 216 LED lights is also available: Chromo Inc. LED CI-216.)

The Process: In both photos, Wayne used camera White Balance settings of 3500º - 3600º K, respectively. This allowed him to more closely match his light painted earthly subjects, and give him a cooler night sky. He also used the WB Shift function in the Menu settings —selecting Blue +2 and Magenta +2, in an attempt to get the sky bluer rather than cyan.

The images were processed in Adobe Photoshop CS6. The adjustments were limited. In Adobe Camera RAW, Wayne increased contrast and performed noise reduction.  In Photoshop,
he selected the sky and canyon walls separately in the Adjustment Layers, and adjusted the contrast for each. He also slightly decreased the saturation of the walls, and slightly increased the saturation of the sky.

Challenges: In "Seeking the Light", Wayne's main challenge was getting uniform lighting on the walls. "I placed the three lights on the ground pointing straight upwards at approximately 20 yard intervals. I found that I had to do a lot of experimenting and adjusting to get them just right. Some lights had to be angled due to outcroppings of rocks. After about a half hour of playing with the lights, I felt they were adequate, and took a number of photos at different angles."

Satisfaction: "My motivation and inspiration for this type of photo came from viewing other photos online, [i.e. Cyclop Arch].  I was attracted to the perspective of looking straight up and viewing the Milky Way, because these give me the most sense of space and depth as well as your relationship to the towering walls. The viewpoint makes me feel small, and somehow makes the stars feel closer. It was my feeling that the fisheye lens was essential for the perspective."

"I was excited when I got under the camera (the screen was pointed down), and saw the images, realizing the set-up would succeed to some degree. Since I had not tried this before at night, I felt like a kid in elementary school that just got promoted!"

By profession, Wayne Pinkston is a Radiologist. Photography and radiology share many of the same principles as far as image capture, processing, and display.

"I look at images all day at work and then go on vacation and take more images. I became interested in photography in college, and that likely influenced me becoming interested in radiolgy. I had a long break from photography while my kids were growing up and rekindled the interest in the 1990's when we were able to travel to national parks as a family."

More of Wayne's photography can be seen at his website, Lightcrafter.



Monday, August 25, 2014

Ocean Lightning by Andre Kleynhans

Lightning strike over the ocean near Key West, Florida ~ © Andre Kleynhans
Nikon D800 • Nikkor 14-24mm f/2.8 lens @ 24mm, f/3.2, 5 seconds, ISO 160
Andre Kleynhans of Cabo San Lucas, Mexico, captured these two spectacular lightning images at night from the 12th deck of a cruise ship, sailing out of Key West, Florida.

Lightning strike over the ocean near Key West, Florida ~ © Andre Kleynhans (click to enlarge)
Nikon D800 • Nikkor 70-200mm f/2.8 lens @ 70mm, f/2.8, 5 seconds, ISO 200
Both images were cropped slightly to Andre's taste. In the top image, he was trying to get the reflection across the water; and in the bottom image his goal was to dramatically fill the frame as much as possible.

Technique: Andre used a five-second exposure time in order to capture as many single lightning strikes as possible. The camera was set to fire continuously, until he had obtained the captures he desired. By keeping the shutter speed to only 5-seconds, Andre hoped to eliminate second lightning strikes within the same frame.

"I am aiming to catch only one lighting strike per exposure. If you leave it open for longer and you do get another lightning strike in the same exposure your 2nd strike will throw off your image due to the fact that the ship is constantly moving, so it will look like you have two images on top of each other, but not aligned —and you could not fix that in post," cautions Andre.

During hurricane season, one can find a lot of thunderstorms in the Caribbean. "The strong winds are usually more prominent along the railing of ship, [but] if you just move a couple of feet back you can escape the most of it," advises Andre.

Challenges: Standing on the open deck of a cruise ship leaves one at the mercy of the elements.

"You have heavy winds, lots of movement and rain that can come out of no where, as it is very dark out in the middle of the ocean. As long as you have a sturdy tripod, and you are set up in such a way that if the rain catches you by surprise, you can pick up your gear and make a run for cover. Make sure you are focused to infinity and try to shoot a little wider than the active part of the cloud; this way you can catch all the action. You can always crop a little bit in post," says Andre.

Tools: A steady tripod was essential. "When I took this image I was standing on deck 12 of the ship (in the front). It is entirely exposed to the wind, so I had to make sure I place my tripod in [a way] to try to avoid as much of the wind as possible. Taking these types of shots at 5 seconds does give you a bit of room to play. A soon as the lightning hits, your image is exposed and you just pretty much wait for the shutter to close again. Its so dark out there in the ocean it actually makes it an easy environment to shoot lightning," says Andre.

Andre used Adobe Lightroom to do the minimal adjustments that he did to the images.

Satisfaction: This was the first lighting storm Andre was able to shoot since upgrading to the Nikon D800, and his expectations were very high. "When I saw that first exposure on the LCD I did a little dance, because I knew that I captured a winner. The satisfaction came when I zoomed in and checked that it was tack sharp. This made standing out there in the 85-degree heat of the Caribbean worth the effort."

Andre Kleynhans was born in Pretoria, South Africa. Andre lived in South Africa until he was 25. After that, he started working on cruise ships, and has been on them now for over six years (he is currently a PADI Instructor). Having the opportunity to see the world ignited his interest in photography.

Andre had always loved taking his dad’s camera from him and being the one taking the family pictures. His career on cruise ships gave him the opportunity to invest in his first camera. Andre learn pretty much everything he knows about photography through self-studying, and is a big supporter of a website called CreativeLive.

Today, Andre shoots with a Nikon D800. He loves landscape photography —anything from sunsets/sunrises, seascapes, the moon or stars —if he has a nice dark evening. He also enjoys doing panoramas, and finds it very interesting to cut up a scene with the camera and recreate it in post production. More of Andre's photography can be found on his website.

Thursday, August 14, 2014

Into the Night with Ben Coffman

"Dust Lanes" - taken in the Alvord Desert of Oregon ~ © Ben Coffman
Ben Coffman moved to Portland, Oregon with his family about four years ago. Even though he bought his first DSLR in 2003, it wasn't until he relocated to Oregon that he "quit goofing around", got serious about his digital photography, and started shooting the night sky.

"Phone Booth Selfie" - The
pay phone booth is the last
of a dying breed. When cell
phones don't have service,
the booth is there to lend a
helping hand, no matter
the hour — "as long as I
had correct change, that is.
...Farewell old friend!"
Ben's biggest challenge in photographing Dust Lanes was the pure remoteness of the Oregon "outback" location, which is of particular concern when one is bringing his entire family, including young children, on a road trip with him. "New tires on the car, a filled 5-gallon jug of water, and plenty of gasoline helped to reassure me that I wasn't endangering us all," says Ben.

"I was also a little nervous about camping in the middle of the desert. The weather forecast suggested a chance of rain, and I've heard horror stories about campers getting stuck out in the middle of the playa when the hard-packed dirt turns to sticky mud."

On this particular night, the skies clouded over during the blue hour, so Ben put away his camera and set his alarm for 2:00 AM, just so he could wake up and check to see if the skies had cleared. At the planned hour, he was thrilled to see a fairly clear sky. The playa, which is mostly white, glowed in the starlight. "What I couldn't see with my naked eye was a thin layer of atmospheric moisture that produced a gauzy, dreamy look to the stars.  ...Rather than fighting it in post-processing, ... I thought the softness fit well with the surreal feel of the landscape," says Coffman.

This photo is two exposures: One for the sky and one for the ground. RAW processing for both exposures took place in Lightroom 5, with blending and other adjustments (local contrast, saturation, sharpening) occurring in Photoshop CS6.

Getting it Right: When I asked Ben about the satisfaction he finds in completing a shot like Dust Lanes, he whipped, "Any satisfaction I would have gained from completing this photo was overshadowed by the amount of frustration involved in finally getting it right! This was actually my fourth full attempt at post-processing it — I have three other "finished" versions of this photo that will never see the light of day because I wasn't quite happy with the final result."

Dust Lanes is part of a larger series Coffman is working on this year, in which he is trying to capture more detailed versions of the night sky than what he had previously captured in his landscape astrophotography. He is trying to illustrate via his techniques that there's more beauty to the night sky than meets the naked eye. He is also trying to raise awareness for the conservation of our night skies (e.g., reducing light pollution via responsible lighting methods).

Ben Coffman shoots with a Canon camera and an assortment of manual lenses. When he is not shooting or "looking at the photos of one of the many, many talented photographers that live in this area", he enjoys coffee, training Brazilian jiu-jitsu, and hanging out with his family, but not necessarily in that order. More of Ben's photography can be found at his website.

Wednesday, August 6, 2014

Using HDR with NightScape Exposures

A "false" HDR exposure of the Milky Way stars reflecting in Oxbox Bend, Grand Teton N.P. ~ © Royce Bair
(Canon 5D Mark III, Rokinon 24mm f/1.4 @ f/2.0, 13 seconds, ISO 6400)
Exposure for sky
When doing my "NightScape" style of starry night landscape photography, I will often do a much longer second exposure (often at 4X longer) and blend the foreground portion with the original "sky" exposure. This enables me to give more detail to mountains, trees, and water features —otherwise, they are are usually just a silhouette against the night sky (like the image to the right).

Second Exposure Problems: Making a longer exposure second exposure is very time consuming because I usually turn on the camera's "Long Exposure Noise Reduction" feature which also takes a "black" exposure for the same amount of time, compares the two images, and cancels out the hot/noisy pixels in your final image. I gladly take this additional time for the increase in quality; however, images with water will also reflect cloud changes (between the exposures) and star movement in the longer, second exposure. Water automatically magnifies the brightest stars and diminishes the lesser stars. It also has a tendency to make each bright star produce a "long" reflection —similar to the way a rising moon reflects on the water. My longer (4X) second exposure greatly exaggerated those lengthy star reflections, causing them to look weird and out of character. To avoid this, and still get better foreground detail I turned to False HDR: False High Dynamic Range Imaging (sometimes called Fake HDR).

Standard HDR vs. False HDR: In regular HDR imaging, one takes at least three exposures: one at the normal exposure value, one at a +1.0 EV (or higher), and one at a -1.0 EV (or lower). These three images are blended, "fused", or tone-mapped together using HDR software, i.e. Photomatix —with the final image extending the dynamic range of the scene.

In False HDR, one manipulates the original exposure to obtain the other two exposure values. This is best accomplished using the Adobe Camera Raw Converter.

In the Adobe Camera Raw Converter, use the "Exposure" slider to obtain your 3 Exposure Values
Save one image at the neutral or "0.00" EV. Save the second image at the "+1.00" EV, and the
third image at the "-1.00" EV (16-bit RAW images can be converted to EV's up to +/- 2.00 stops).
Here are my three converted images: Normal exposure, +1.00 EV, and -1.00 EV.
These are saved as 16-bit TIF files.
HDR Processing: The above three exposure values were save as 16-bit TIF files and imported into Photomatix for HDR processing. I typically output a "Natural Fusion" image that just blends the three images and extends the dynamic range of the scene. I then output a tone-mapped version that gives additional local contrast, texture, and shadow detail. The Natural Fusion and tone-mapped versions are then blended using Photoshop's Adjustment Layers, varying the opacity of each layer to taste. Additional contrast is then applied to the final image via an S-curve to bring out the latent colors in the sky.

Tuesday, July 15, 2014

Finding the Milky Way with Sky Guide

Knowing when and where the Milky Way would appear over this alpine lake was easy with the Sky Guide app.
Sky Guide makes it easy for astro-landscape photographers to know in advance when and where the Milky Way will appear over any landscape feature in the world. Sky Guide is a star and constellation guide app designed for both iPhone and iPad (not available for Android).

Compared to Stellarium: For the last two years I have used and recommended the free, open-source, planetarium desktop program, Stellarium. Why? Because Stellarium can look into the future and tell you where the stars and the Milky Way will be positioned on any day, and at any location on the earth. There are dozens of star reference apps out there, but very few can do predictions.

Despite Stellarium's lofty position with many astronomers, It's a love-hate relationship for some. It's a program designed by geeks, for geeks. Although Stellarium is very accurate, it's anything but user friendly. Sky Guide is less exact, but it is elegant and fun to use.

A Stellarium screen capture where the latitude and longitude grids were applied to help better define positions.
Sky Guide only shows the eight major compass headings (i.e. N, NE, E), but images are very elegant and realistic.
Both Sky Guide and Stellarium use preference settings to display or remove mythology or folklore. 
Stellarium is plain vanilla compared to Sky Guide's more realistic displays —which were developed from over 37,000 actual photographs of the night sky! However, when you need super accurate predictions of the Milky Way's alignment with landscape objects, Stellarium will allow you to drop in a grid (placed every 10º); whereas, Sky Guide only displays eight compass headings —requiring you to interpolate within the 45 degrees between each heading.

Sky Guide Features: I was impressed that Sky Guide functioned with or without a Wi-Fi, data, or GPS signal, as I was able to use it in true wilderness conditions, and it worked flawlessly. I loved the visuals in this star app. With the high-resolution photographs in this app you’ll see millions of stars—not just a few thousand simulated points. You can also control the intensity of star light with HDR brightness gestures to dial in your local viewing conditions. Here is a list of features:
  • Rich content: Generous amounts of stunning graphics, original artwork, and detailed articles. 
  • Soundscape: Designed by Mat Jarvis, the most featured composer in the award-winning soundtrack for the game Osmos. Stars have sounds based on their temperature and size.
  • Useful anywhere: Works with or without a GPS or data signal. Built-in access to hundreds of articles no matter where you are.
  • Time controls: Know where objects will appear in the future with cinematic time-lapse effects.
  • New as of vesrion 3.2: Filter: X-ray the sky and explore invisible wonders. More languages! French, Italian, Spanish, Portuguese, Russian, Japanese, Korean, Chinese (Traditional) and Chinese (Simplified).
  • HDR brightness gestures: Dynamically control how bright the sky is to match how many stars you can see under light-polluted skies.
  • Red night mode: Preserve your dark-adapted eyesight.
Most Important Features to the Astro-landscape Photographer: I think Sky Guide's best features are its Time Controls: giving you the ability to see where objects like the Milky Way will appear in the future —and with very cool cinematic time-lapse effects!

Time Controls Demo: The best way for you to appreciate this great feature is for me to demonstrate how Sky Guide helped me plan for the photo at the top of this post. Here is an iPhone panorama I took of the area the day before:

A 180º iPhone panorama of a small alpine lake in Utah's High Uintas.
Cropped version of the above image: My plan was to photograph the Milky Way in a near vertical
position, just slightly to the left of center. I knew from previous experience that the MW would
be in the southern part of the sky in the late evening, but I didn't know exactly when or where.
This is where Sky Guide comes in...
Top middle "Compass" button lets
Sky Guide use your current location
My iPhone compass indicated that the area where I would like to have the Milky Way appear in my photo was at a heading of 210º —only about 15º to the left of a SW heading (225º). The big question was what time of night would the Milky Way be in that position, and how would it appear in the sky? I was hoping for a more vertical MW for the ultra wide angle, vertical composition I had planned (using a 14mm lens, with a 114º angle of coverage).

It was currently about two hours before sunset. Using Sky Guide on my iPhone, I touched the "Compass" button at the top of the screen. This allows SG to use my current position and show me what the sky looks like right now, both above and below the horizon. By swiping up, with my finger, from the bottom edge, I am able to get SG to reveal the Time Center at the bottom of the screen.

It's currently 6:48 PM —about two hours before sunset. With the iPhone (an older 4s model) facing
between the East and SE, I can see that the Central Bulge of the Milky Way is still below the
horizon, and lying in a horizontal position to the horizon. By swiping up from the bottom
edge of the screen I have activated the Time Center and I'm ready to do
some serious time travel. Let the fun begin!
Although Sky Guide's mythology or folklore is helpful in locating the star constellations, I decide to turn this and the "Labels" feature off, in order to see an uncluttered view of the night sky. This is quickly accomplished via the Menu > Preferences.

Now the magic begins. With the Time Center activated at the bottom of the screen, I touch the fast forward button (double arrows on the right). Your first tap give you real time, "1x" forward speed. A second tap gives you "10x" forward speed. A third tap equals "100x". A fourth tap = 1000x, and so on. Now, the sky is really moving in a time-lapse, cinematic fashion! At about 11:15 PM I tap the pause button to review the sky...

(I've rotated my iPhone to the horizontal positions for a wider view of the horizon, and turned off
the mythology and label.) With the Time Center fast forwarding @ 1000x, it only takes about
14 seconds to time-lapse from 6:48 PM to 11:15 PM! The Milky Way has rotated during
this time from a near horizontal position to about a more diagonal position, with the
Central Bulge high in the sky, and in a near South heading.
I again use the Time Center's fast forward button to go forward @ 1000x until the Milky Way is in a near vertical position. To my joy, it is also positioned just before the SW compass heading, or about 210º! The Time Center tells me the time in the future will be about 2:44 AM for this shoot.

Fast forwarding (@ 1000x) until the Milky Way reaches a near vertical position, I tap the pause button
and check the MW's position and date in the future: Just left of the SW (225º) heading and
2:44 AM in the future (early tomorrow morning).
I then rotate my iPhone back to a vertical position and move it around until I get the composition I like. With this snapshot into the future, I have a good idea as to when and where I will take my real NightScape early the next morning.

Compare this Sky Guide "into-the-future" composition with the final NightScape I shot (at the top of the
page) —taken at 2:42 AM. The differences: My atmospheric conditions were somewhat different, with
airglow and a little light pollution on the right side (coming from Salt Lake City, about 60 miles away,
"as the crow flies"). My final shot is with a wider angle lens (a 14mm with 114º angle of view). The
other differences are the reflection in the lake and the tree line above the horizon that obscures
part of the Milky Way and the large star, Antares.
Planning for other Locations: Like Stellarium, Sky Guide can also help you see into the future at locations that are not your "Current Location". Go to Menu > Location and choose the "Manual Location" option. You will be presented with a list of countries in the world. Touch the country you want, and you'll get a list of major cities in that country. Choose the city closest to the location you want to plan around, and the coordinates will appear right under the "Manual Location" heading.

Limitations: I only wish Sky Guide would also allow you to put in your own coordinates, rather than choosing a city closest to your destination. In the example to the right, I had to choose "Salt Lake City, UT", which was about 60 miles from my alpine lake location —other smaller cities and town that were much closer, were not on SG's list. (Keep in mind that being 60 miles off from the actual location will only affect your positioning of the Milky Way by about two or three degrees and less than five or six minutes off in timing.)

Other Time Control Adjustments: If your next NightScape photo shoot is months into the future, you can also use the Menu > Time & Date and choose the "Select Time" feature. This will get you closer to your date, and then you can use the Time Center fast forward controls. I've also used this feature to go back in time to help me identify a star or constellation in one of my photos.

Conclusion: Pros: For only $1.99, Sky Guide is a steal! It is truly elegant, and easy to use. The "Time Controls" place this app's usefulness way beyond other products for the astro-landscape photographer (and for photographers, no other product, with their "simulated" stars will do once you've used SG)! Cons: Although the ability to manually set your location via a country and city list is a great option, having the ability to manually set your own coordinates would have been even better. And, having the ability to drop in a grid of longitude and latitude would increase location accuracy, but I understand the limitations of a small screen, so I'll not complain too loudly on this one.

Sky Guide is available through the iTunes Store for $1.99. It has a 5 out of 5 star rating on both the current (3.2) version (1200+ ratings) and all previous versions (8600+ ratings).


Android Version? Sky Guide is not currently available as an Android app. The closest thing I can suggest is SkySafari ($2.99).

Royce's 2014 Workshop, Lecture & Video Conference Schedule: NightScapeEvents.com


Thursday, July 10, 2014

The Edge Of Perception by Michael Shainblum

"The Edge of Perception" - an illustrative Milky Way photograph by Michael Shainblum (click to enlarge)
Michael Shainblum recently took our Photo of the Week at one of his favorite spots in California —along the Armour Ranch Road in Santa Ynez. Michael loves the rolling hills with the giant oak trees, as they make for awesome foregrounds with the Milky Way. The bright spots on the horizon are not the sun setting, but actually light pollution from Los Angeles county —proving that the distant glow from city lights can be a wonderfully illustrative tool in the right hands!

Technical Stuff: Michael used a Canon EOS 6D. The Milky Way was tracked for 60 seconds using a Vixen Polarie, and then brought into another 60 seconds land exposure, with the tracking off. This helps to produce and cleaner (lower noise) and sharper look. The post processing was made to retain all the true color spectrum of the Milky Way "without being too jarring or too contrasty".

Challenges: "It was annoying because [jet] contrails kept appearing in the sky and they were too big to be photoshopped out so I sat out there for an hour just to wait for the contrails to dissipate," says Michael.

Michael Shainblum
Satisfaction: "My main goal was to show a surreal, yet realistic scene. The name 'The Edge Of Perception' came from starring at the image on me screen blankly for an hour. I finally started thinking some of these images really do capture the unknown and the almost intangible. These Milky Way images really do fall on the edge of our perception and of our reality," reports Michael.

Michael Shainblum is from San Diego, California. He graduated from Brooks Institute of Photography in Santa Barbara, and now lives in San Francisco. More of Michael's work can be seen on his website. He also teaches workshops for photography and timelapse via Skype.


Royce's 2014 Workshop, Lecture & Video Conference Schedule: NightScapeEvents.com


Wednesday, July 9, 2014

Rokinon 24mm f/1.4 Review

The Rokinon 24mm f/1.4 compared to the Canon EF24mm f/1.4 on the right ($550 vs. $1750)
The Rokinon 24mm f/1.4 ED AS UMC Wide-Angle Lens is hybrid aspherical that is particularly suitable for astro-landscape photography because of its excellent correction for coma aberration, even when used wide open.

Although I have long recommended this and two other lenses made by the Samyang Optics, I have recently received several email messages from prospective buyers, worried about negative reviews they have seen about this lens. This lens is not for general use. It is a totally manual lens —no electronic linkage to the camera, whatsoever. Despite this, it is well suited for astro photography.

Advantages of a f/1.4 Aperture: I have several lenses that I use for astro-landscapes. All but the Rokinon 24mm lens have f/2.8 as their widest aperture. The Rokinon 24mm's f/1.4 provides several nice options.

  • Using f/1.4 allows you to lower your ISO, or...
  • Shorten your exposure time (to reduce star trailing), or...
  • Do both: reduce ISO and shorten your exposure time, or you can...
  • Stop down to f/2.0 to increase sharpness and reduce lens vignetting

A typical exposure with the an ultra wide angle lens is f/2.8 for 25 to 30 seconds @ ISO 6400. With the 24mm f/1.4 you could go f/1.4 @ for 25 to 30 seconds @ ISO 1600. However, because of it's longer focal length, you'll get less star movement by going 13 to 15 seconds @ ISO 3200. And if you've got a good low-noise camera sensor, you won't mind going to ISO 6400 and closing down to f/2.0 for the increase in depth of field (for close foreground objects) and significantly reducing the lens' vignetting (see "My Personal Preferences", below).

Comparison: Let me share a comparison I did with my $1,750 Canon EF24mm f/1.4L II USM and the $550 Rokinon 24mm f/1.4. (The Rokinon is also branded as a Samyang or Bower. They are all the same lens, made by Samyang Optics.) The following test photos were taken about 15 miles away from Salt Lake City, at the Brighton Ski Resort. Being this close to SLC, the skies are still polluted with light from the valley below, but for a 30-minute drive, it still allows one to record the medium to bright stars.

Night Ski above Brighton Ski Resort ~ Taken with the Canon EF24mm f/1.4 @ f/2.8
(This lens must be stopped down to at least f/2.8 in order to correct its coma aberration.)
At f/2.8, the Canon performed slightly better than the Rokinon, but at f/1.4 and f/2.0,
the Rokinon out-performed the Canon in sharpness and coma correction.
The following images are directly from the camera JPEGs with no post-processing correction for white balance, noise, or lens vignetting:

Full-Frame comparisons: The color rendition of the Rokinon is slightly different from the Canon,
but the most significant difference is lens vignetting. For the extra $1,200 you pay for the
Canon lens, you get about one-stop less lens vignetting in the corners. However, this
can easily be corrected in the Adobe Raw Converter software. (Click to enlarge)
Center enlargements @ 100%: Neither lens exhibits coma in the center, but the Canon is slightly
less sharp and has a touch more color fringing (click to enlarge).
Edge enlargements @ 100%: The Rokinon exhibits about 1/2-stop fall-off on the edges, and about
1-stop fall-off in the corners compared to the Canon. Sharpness is about the same.  However,
the big difference is coma. Canon's coma in the edges and corners is so bad, it's off the chart;
whereas the Rokinon exhibits only minor coma aberration, albeit some color fringing.
(Click to enlarge. Note: the "stick" in the sky is a snow marker for snow plows.)
Manual Focus: the Rokinon is manual everything, including focus —which is not a problem, since auto
focus doesn't work in the dark, anyway! As with any lens used for starry night photography, I find it
a good idea to focus on an "infinity" object (i.e. a tree on the horizon, about 200+ feet away) during
the daytime. I use the camera's "live view" function and magnify my image 10X on the LCD
screen. I've marked that position with a green dot on the lens focusing ring (green turns
black under red headlamp light). The red dot is this lens' 50 feet mark.
Angle of view: About half of my NightScapes are taken with a 14mm (114º angle of view), and the other
half with the 24mm's 84º angle of view. You can capture more of the sky with the 14mm, but when
I want to emphasis the beauty and drama of the Milky Way's Central Bulge, the 24mm is a
perfect fit!  ~ Alabama Hills with the 24mm Rokinon, @ f/2.0, 13", ISO 6400.
My personal Preferences: About 80% of my Rokinon 24mm shooting is done at f/2.0. I prefer to stop down for a little extra sharpness, better depth of field for foreground objects, and a significant reduction in lens vignetting (even though this can be corrected in software, you do run the risk of color cross-overs in your corners, which can also be corrected, but it is an extra post-processing hassle that I'll discuss in another blog post, someday). My typical exposure with my Canon 5D Mark III is f2.0, for 13 seconds @ ISO 6400. This short exposure produces extremely sharp and almost perfectly round stars. Even a two second increase to 15 seconds can sometime produce elliptical-shaped stars, and a 20-seconds exposure is almost sure to have some significant star movement. Mind you, this movement is only noticeable in large prints of 20x30 inches or larger —but that's the kind of quality I'm shooting for.

Conclusion: I find the Rokinon 24mm f/1.4 lens offers great performance, especially when one considers the price. The advantage of having an f/1.4 aperture in your arsenal of lenses provides many options that other lenses don't offer.

Pro: Low price. Good sharpness. Excellent coma corrections. Fast, f/1.4 aperture. Good construction. Cons: Significant lens vignetting, but this can be mostly corrected with software. Many non-critical (low-tolerance) components are made of plastic to reduce cost. This does not affect performance, but can affect long-term durability in rough environments and handling. Manual everything: Manual focus, manual aperture, and no electronic coupling to your camera body (no EXIF info can be transmitted to the image file).

The Rokinon 24mm is available through B&H in the Canon mount, Nikon mount, and Sony mount. Note: The Nikon mount includes an electronic focus confirmation and auto aperture chip that adds about $50 to the price.

Royce's 2014 
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