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Monday, November 26, 2012

NASA's Dial-A-Moon Tool

Last week, NASA released an incredible video showing the Moon’s motion and phases over the whole year of 2013, where each frame of the video is one hour of time! It’s mesmerizing:


If you have the bandwidth, change the resolution to full, 1080p HD (using the cog icon at the bottom right) -- the extra quality is worth the watch!

The animation uses data from the Clementine lunar mission, a joint NASA and military probe in the 1990s to map the Moon, as well as images and topography measurements from the Lunar Reconnaissance Orbiter. The surface-elevation measurements were used to create the realistic shadows in the animation.

You'll noticed that the Moon appears to rock around, tipping, and tilting over the course of every month. That’s called libration, and is due to the Moon’s orbit being elliptical, as well as the Moon's rotational axis being slightly tilted with respect to its orbit.

There are many other extras to this video, like the scale on the right showing how far the Moon is from the Earth in units of the Earth’s diameter (about 13,000 kilometers, or 8,000 miles). You can watch it oscillate back and forth as it orbits, moving from 28 to 32 times the Earth’s diameter away.

At the bottom right is a huge amount of information that changes with time, including the Moon’s distance and its apparent size, measured in arcseconds. There are 3,600 arcseconds in a degree, and a full Moon is roughly 1,800 arcseconds, or a half degree across.

DIAL-A-MOON Tool: Although the video is fun to watch, NASA's website for the animation may be more useful for night photographers. This site contains all the individual frames used to animate the Moon phases and libration. Their Dial-A-Moon tool will allow you to pick any month, day, and hour of the year and see that phase of the moon (a lot easier than trying to adjust the video)!

Rising and Setting Times: Knowing the phase of the Moon is great, but a night photographer also needs to know the rising and setting times of the moon on any given day. For that you'll also need this USNO table. This table can be changed to show the rising and setting of either the sun or the Moon.

Position of the Moon: Wouldn't it also be nice to know where the Moon would be in the sky on any night and hour? The free planetarium software, Stellarium, can do this for you. All you do is tell it where you are on the earth and what time of the day or night. You can advance or go back to any day, hour, minute, and second in time (you can also speed up time and watch the sky move quickly or slowly). Using the coordinates and time you give Stellarium, you'll be able to see exactly where the moon rises and sets, or where it is in the sky at any hour (as well as all the stars, constellations, and the Milky Way)!

Friday, November 23, 2012

POTW: 'Something Different' by Dan Barr

"Something Different" ~ © Dan Barr (click on image for a larger view)
This unique star trails photograph was taken in Culp Valley within Anza Borrego Desert State Park. (Culp Valley is about 12 miles west of Borrego Springs off of the State Highway S22 and is accessible by a 4WD road.) Dan Barr captured this image with his Canon 40D, using a Tokina 11-16 f/2.8 lens (additional EXIF: focal length was 11mm, 30 second exposures at f/2.8, ISO 1600). This is a "stacked" star trail. Dan used 135 individual exposures to make a composite in Photoshop.

Technique: Barr decided to try a new processing technique for this star trail. He usually assembles his star trails in Photoshop by opening all the images as a layered document and changing the blending mode of each layer to "lighten" to create the trails. This time he thought it would be fun to try to make tapering trails to give the star trails a meteor-like effect. He made the tapering trails by varying the opacity of each layer in Photoshop.

The "tapering trails" idea became somewhat of a pain in the neck! Dan changed the opacity in 5% increments so there was roughly seven images for each increment descending from 100% to 0% opacity. It involved considerable trial and error to get a degree of taper he was finally happy with. Finally, to top it off he increased the exposure and contrast of the first exposure in the star trail stack to accentuate the stars and create kind of a cap for the fading star trails. The resulting image was very different from any of his previous star trails, and he had a lot of fun trying something new.

The light painting was completely by accident! "I was fumbling with my keys and accidentally pushed the unlock button on my car remote," says Barr. "The sidelights and interior lights came on briefly and illuminated the boulders. I usually don't worry to much about stray light in my star trails since I can usually mask it out when I am assembling the image in Photoshop. In this case I liked the the effect from the car lights, so I left it in."

Challenges : "For me the biggest challenges in taking this photo were compositional and in post-processing to assemble the final image," said Dan.

After taking many star trails he has learned that he likes to try to include some of the landscape into the shot in addition to the foreground elements to give the final photo a feeling of depth. Dan wasn't happy with the topography of the surrounding landscape so he just decided to fill the bottom half of the frame with boulders. Still, he was worried that he was going to end up with a boring two-dimensional photo.

Satisfaction: "When I actually got home and started assembling the image, I was pleasantly surprised. The light from my vehicle provided some dimensionality to boulders, and I was pleased with the overall framing," reports Barr.

More of Dan Barr's photography can be seen at his Flickr photostream and his website.

Friday, November 16, 2012

POTW: 'Birthday Girl' by Aaron M Photo

"Birthday Girl" ~ © Aaron Meyers (Aaron M Photo). Click on photo for a larger view.
This 75th Birthday of the Golden Gate Bridge is our featured Photo of the Week. Aaron Meyers photographed it with a Nikon D700, using a Nikkor 24-70mm f/2.8G ED AF-S @ 40mm, f/9, 3.3 sec, ISO 200. Aaron set the camera on bulb mode so he could control how long the shutter was open. It was shot just below "Slacker Hill" in the Marin Headlands. There was no manipulation of this image other than Lightroom and Photoshop for standard clean up.

Challenges: Fog was predicted for this evening so there was worry that the entire thing would be skunked and the fireworks wouldn't be visible. The location Aaron wanted to use, Hawk Hill, is lower in elevation than Slacker Hill and he feared if he went to the lower spot it might be in the fog. Meyers decided to go to a higher elevation and hope that if there was fog he might get fireworks coming out of it. As it turned out, there wasn't any fog at all and any location he would have picked would have worked.

Another obstacle to overcome was that fireworks can be blown out if you keep the shutter open too long. Depending on how long the fireworks lasted, Aaron knew he would have to quickly raise or lower the ISO. If he wanted to capture a lot of fireworks he would lower the ISO to let more of the fireworks be captured without clipping. If he just wanted to highlight a quick section of the fireworks, he would increase the ISO so he could get the color and details. He also wanted to keep the ISO fairly high because the lights on the bridge had been turned off and the bridge just looked black if the ISO was too low. "It was a constant struggle the entire night to get enough exposed without over-exposing," says Aaron!

Satisfaction: Aaron knew this was going to be a special event and he was excited to photograph it. Once he saw the weather was going to hold out and there wouldn't be any fog he started to get even more excited. Choosing the "best" spot to photograph became a tough decision.

"I was running all over, back and forth between places trying to decide," says Aaron. "Once the fireworks started I knew this was going to be a special day. The committee that organized the fireworks did a beautiful job and this was the best fireworks show I had ever seen -- complete with lasers, sparklers, fireworks, and more. It was truly a breathtaking experience. I know everyone around me, myself included, left in awe."

More of Aaron's night photography can be seen at his website.

Friday, November 2, 2012

Jack Fusco: Finding Darkness in New Jersey

"Night Watch" ~ Cape May, NJ ~ © Jack Fusco
Living in New Jersey is definitely the biggest challenge for starry night photographer, Jack Fusco. New Jersey is the most densely populated state in the U.S. so escaping light pollution isn’t an easy task and often feels quite impossible! Because areas near the ocean have the least light pollution, much of Jack's work takes on a bit of a nautical feel.

"When I started photography, I was very big into seascapes and have finally found myself back at the ocean, but more recently under the stars, instead of waiting for the sun to rise. 
After I took my first set of star trails I was immediately hooked on night photography. It was a lot of experimentation at first, but each night was more exciting than the night before. I found myself out shooting any time the skies were clear driving around trying to find new places to shoot or visiting places that I had shot before, but only during the day. Before I knew it I was driving further, sleeping less, and drinking much more coffee!" says Jack.

"Live Endlessly" ~ Strathmere, NJ ~ © Jack Fusco
This photo near Strathmere, NJ is a typical example of his frustrations and his ecstasy. After a few weeks of bad weather or just bad timing, clear skies were finally in the forecast. Fusco excitedly headed out to a spot he had been waiting to shoot only to notice a haze settling in. Jack decided that it had been too long since he was able to last shoot, so he was going to carry on towards his destination. "I stayed positive and continued on hoping it would clear up by the time I got there, but didn’t have such luck," laments Jack. Still determined to shoot, he decided to explore some areas other areas in Strathmere. He continued to found himself staring at nothing but hazy skies, but looking out east over the ocean he saw a sky full of stars. He was able to set up just in time to catch the Milky Way rising over the ocean and spent the next few hours relaxing out on the sand!

"Finding Sirius" ~ Ocean City, NJ ~ © Jack Fusco
After three hours of shooting star trails Jack decided to take a few extra minutes before making the drive back home, and ended up taking this shot. Aside from being one of his favorite shots, it serves as a reminder to him to keep looking beyond what his plans. It reminds him to not just plan his shots, but keep an open mind and always remember to have fun while he's shooting.

"Star Shepherd" ~ Acadia National Park, Maine ~ © Jack Fusco
Fasco sometimes travels to neighboring states for his star photography. The Bass Harbor Lighthouse is at the top of his list when he visits Acadia National Park, Maine — a 12 hour drive from his home in Toms River, NJ. He stayed out until around 3:00 am to take this panoramic, before starting the long drive home.

"Sea Isle Stars" ~ taken w/ his new D800E
Equipment and tools: Jack just recently made the big switch from Canon to Nikon. He's very excited about his new setup for shooting the stars which consists of a Nikon D800E and a Nikkor 14-24 f/2.8. Unfortunately, the weather conditions haven’t allowed him much time to really get out and push his new gear, but so far he couldn’t be happier with the results he's been able to get.

His most valuable tools have been web sites like ClearDarkSky, (light pollution maps and clear sky charts) and apps like Star Walk (astronomy guide). A lot of pre-planning goes in to his shots and both tools are integral parts of his process. Jack first uses the ClearDarkSky site to find new locations and monitor the conditions in those areas. After he as picked out a location, he then then uses Star Walk to figure out exactly when he needs to be there for what he planned on shooting. Editor's Note: Dark Sky Finder is another tool that can be used to find the darkest skies in your area.


What Drives Jack's Night Work?  "I find photographing the night sky to be rewarding on many levels. After driving for hours to get as far from light pollution as possible, there’s a huge rush of excitement when you first get out under the stars. It’s like an entirely different sky that you’re looking up at compared to what I see when I step out of my house. After running around and getting all set up to shoot, you then get to relax and take in all of the beauty of a star filled sky.

"I often have people make comments about how I must have a great deal of patience to sit out there while taking stars trails, but it really couldn’t be further from that. I find the time spent out there to be like an escape from the rest of the world. Once the shot is all finished and ready to be posted online, seeing positive or excited reactions to it is certainly a great feeling... Hearing that someone wants to go explore and get a good view of the night sky after seeing my work is a really amazing thing to hear. [It] is probably one of the best compliments I can receive."

More of Jack Fusco's work can be found on his website and his Facebook page.

Editor's Note: The day I interviewed Jack (via the Internet), Hurricane Sandy was about to make landfall. Fusco's home town of Toms River, is only about a mile inland from one of the hardest hit areas of New Jersey: Seaside Heights and Seaside Park! As I finish writing this, I can't help wonder how many residents wouldn't mind having more connected power and light pollution at this moment (See satellite view of Hurricane Sandy's mid-Atlantic blackout)! I still have not been able to make contact with Jack, but he did manage somehow to post this message on his Facebook page: "We were very fortunate and made it through the storm okay. We're still without power, but certainly lucky to have what we do. There was an incredible amount of loss that is still difficult to fully comprehend. My thoughts are with all of those that have and that still are going through this tragedy." I ditto Jack's concerns, and hope many will join me in making a contribution to a relief charity of their choice.