Jupiter Mars Conjunction January 6-7, 2018

Moon, Mars and Venus Setting over Mount Whitney

A past conjunction: the moon, Mars and Venus setting over Mount Whitney

The planets in our solar system orbit the sun in a plane, the “ecliptic plane”.  Seen from the side within that plane from here on earth, they appear to travel in a line in the sky.  As the planets travel in different orbits at different speeds, they sometimes seem to pass one another along that imaginary ecliptic line in the sky, as seen from here on earth. From the United States, the pass will occur between the mornings of January 6 and 7, 2018. Mars and Jupiter will pass within 1/4 degree, 1/2 moon width, of each other.

For the image above from the moon, Mars, Venus conjunction on February 20, 2015, I identified several locations to the conjunction as the moon and planets set over Mount Whitney, near Lone Pine, California. This time the planets will be about 3 times closer to each other.

Here are some actual photos of Jupiter and Mars approaching each other in the sky on recent nights:

Jupiter Mars Conjunction January 7

Jupiter and Mars on December 30, approaching conjunction January 6/7 2017

Approaching Jupiter Mars Conjunction

Jupiter and Mars January 2, rising before dawn

Astrophotographer Jeff Sullivan

On January 5 Jupiter and Mars continue their approach towards conjunction January 6

Here’s a time-lapse of the planets rising on the morning of January 2:

The images and sample time-lapse were captured at a modest 200 mm focal length, the event will be more interesting when they are close enough to shoot at 300-400mm or more, their movement towards each other becomes even more obvious, and while the moons of Jupiter become even more apparent. The two planets will rise over the eastern horizon around 2:45 am on a zero degree horizon here in the Pacific time zone (at a compass angle of 112 degrees, a bit south of east), but I’ve been watching them past 6 am on recent mornings, so you can catch them from when they rise well into twilight. With my actual horizon being more than zero degrees, the planets will appear to rise closer to 3 am for me.

Here’s my result showing the progress of the planets, footage from the mornings of January 2, 3, 5, and 7:

Aside from the planets close together, what else might have been shot? With a long enough exposure and an interesting horizon, a time-lapse video of the planets rising could be interesting, somewhat like this prior shoot of a planetary conjunction setting:

Moon – Mars – Venus Conjunction Setting Over Mount Whitney from Jeff Sullivan on Vimeo.

I chose not to travel to an interesting landscape for this event due to a stormy weather forecast for much of the week here in the Eastern Sierra, including rain on January 6.

Venus Jupiter Moon Conjunction

Venus Jupiter Moon Conjunction, August 23, 2014

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How to Spot Comet PANSTARRS in March

Find Comet PANSTARRs in the twilight sky

Based on global reports from Saturday, March 9, it seems that no one is reporting success yet seeing the comet from the Northern Hemisphere.

One of the easiest evenings to find it may be Tuesday night March 12, when it’s essentially just to the left of the setting thin crescent moon, and very close to due west.  On our arrival date for the Death Valley workshop this week March 13, the crescent moon will be easier to spot and the comet will be below the moon and slightly to the right.

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How To Create a Time-lapse Video of a Meteor Shower

Perseid Meteor Shower, August 2013

The Perseid Meteor Shower runs from July 17 – August 24, with peak night occurring around August 12-14. When shooting night landscapes and trying to catch meteor showers, I like taking long exposures one after another, so you catch anything which flies through your camera’s field of view. If you shoot continuously for a while and catch a couple of hundred exposures or more, you can even assemble those shots into a time-lapse video.

Lets do a little math to figure out how your still shots will transfer to video. When deciding how long to shoot, bear in mind that this is a time-lapse video, so in playback as video everything is dramatically sped up. Each frame is a 5 to 30 second shot, but video is 24 or 30 frames per second. To make the meteors last more than 1/30th of a second, you may want them to be present for two frames of video, and assemble your video at a relatively slow frame rate of only 12 shots per second, so in video formats that play at 24 to 30 frames per second, the meteors show up for at least two frames. Fortunately our eyes and minds are quick enough for us to perceive the meteors with some persistence even though they show up for only 1/12th of a second.

On a dark night your exposures may be 30 seconds or more, so at 24 frames per second each hour of shooting will give you less than 5 seconds of video. With the nearly full moon last night, there was enough light that I was able to reduce my exposure time to 5 seconds. I set an external timer (intervalometer) to take the next shot one second later, so I took one very 6 seconds, or 10 shots per minute. So if I’m using a slow frame rate of 12 frames per second to make the meteors more persistent in the video, I’ll end up with almost one second of video per minute of shooting.  Adjust your exposures per minute and video frames per second math to figure out how fast you want your shooting sequence to play back.

If you’d like to explore time-lapse photography yourself, download the free VirtualDub software which can convert a sequence of JPEG files into video, and check out the forum on www.Timescapes.org for discussions on techniques. You’ll need a tripod of course, and your sequence of still images will turn out best if you use a remote switch that has an intervalometer (timer) function.

Update March 2016: One more thing, meteors are more common after midnight, so I usually arrive on site around 11 pm to give myself an hour to set up before I have to start shooting.  Basically where you are on earth starts to rotate around to the front of the Earth’s path through space at midnight, so the sky above you collides with more comet dust from then until astronomical twilight starts before dawn, as this article explains: Ask the Naturalist: What’s the Best Time and Place to See Meteors?

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How To Capture Milky Way Images

Milky Way, originally uploaded by Jeffrey Sullivan.

Many digital cameras these days can do surprisingly well at capturing images at night. Their sensors are more sensitive than your eyes, especially at capturing color at night.

Photography has always involved multiple steps, with exposure being only one part of the equation. In the days of film, the darkroom enabled additional influence to be applied during development, and then again during printing. Unless you were using a Polaroid camera, there was no such thing as “straight out of the camera.” Maybe you trusted someone in a drug store to do your developing and printing for you, but that wasn’t an optimal situation and that certainly doesn’t mean that no adjustments were made. For the most part, the entire concept of “straight out of the camera” is a myth that is best set aside as soon and as thoroughly as possible.

Today with digital cameras your darkroom is on a computer, implemented in software. Milky Way shots are a great example of images that you won’t get the most out of until you get in the habit of spending 5 minutes in your digital darkroom to complete the photographic process.

If you find a dark place outdoors to shoot and you can make out stars and the lighter, more dense band of the Milky Way, a little postprocessing can get you a lot further. As with my previous blog post you need to shoot on a tripod, using manual aperture and manual focus. Having your long exposure noise reduction turned off is not critical since we’re dealing with single exposures for Milky Way shots.

Shoot with your widest focal length lens to minimize star movement in the field of view, have it opened to its widest aperture to minimize exposure time. You may still have little enough light that you shoot at the longest exposure time (generally 30 seconds) or you may need to shoot in “bulb” mode for a longer time in order to get enough light. Always shoot in RAW mode so you have far more adjustment capability in post-processing software.

Shoot near the date of a new moon, so there is as little light pollution as possible. The last thing you need to know, probably the most important thing during planning your shot, is how to predict when the most intricate, dense, bright center of the Milky Way is in the night sky! In Summer the sun is up roughly 2/3 of every day, but the Milky Way crosses the sky in the night. The center of the Milky Way is towards the constellation Sagittarius. You can look up the dates when Sagittarius is high in the sky, and that’s when the Milky Way is most intense: http://homepage.ntlworld.com/mjpowell/Astro/Sgr/Find-Sagittarius.htm
If you have a smart phone, you can also use astronomy applications such as StarWalk and change the date and time to see when the Milky Way rises on the eastern horizon.

In simple terms, it highest around midnight on the Summer solstice June 21, two hours later per month earlier (2 am in May), two hours earlier per month later (10 pm in July). So really your best shooting will be on days near the new moon dates, and preferably within 7 weeks or so of June 21:May, June, July and August.  If you want to shoot at night right after the sun sets however, instead of getting up in the early hours of the morning, the Milky Way doesn’t rise early in the night until Late May or so, which is why many people favor the summer months June through August for Milky Way shooting.

So lets assume you go out on the right night, shoot south towards Sagittarius, capture a RAW file with some stars showing, and maybe you can barely make out the bright stripe of the Milky Way and its slightly more dense center.

Well, if you were in a darkroom… how do you lighten the Milky Way while keeping the background sky dark? The simple answer is dodge and burn… selectively darken some areas while lightening others!

In Adobe Lightroom (download a 30 day trial if you don’t have it already, AFTER you collect some images to process) use the paintbrush tool (under the Develop module) to select and lighten the area around the Milky Way. Use the paintbrush tool to darken the sky everywhere else (this makes both the Milky Way and the stars pop).

to do even better, you can also increase contrast while performing these functions, further darkening background light levels, including noise. Adjust exposure and brightness so the fainter stars in the Milky Way get brighter while background and noise gets dark. You can increase saturation slightly on the Milky Way, but increasing contrast has that effect already, so you might not need to.

Don’t worry too much about how much noise your camera produces… after you adjust contrast and brightness, just crank up the noise reduction. After all, there isn’t generally much detail to lose by doing that. In Lightroom for dark, noisy photos I try to max out noise reduction at 25 or maybe 30, but lately for night skies I’ve been going into the 60s.

Lightroom can also selectively adjust saturation and brightness of individual colors. If you shoot too close to sunset and “blue hour”, or during a too-bright moon that is too full (and creating blue night sky), it can be handy to darken a blueish background sky to help separate that from the stars (just did that on a star trails shot). On the other hand for dark new moon skies, like you should have if you’re planning ahead for Milky Way shooting, there is little or no light scattering turning the sky blue. A lot of the Milky Way stars have a slight blue tint though, so selectively raising brightness of blue can help separate them from dark background and any noise.

It’s a balancing act between white balance, adjusting individual colors, and tweaking the brightness and especially contrast of the area the Milky Way covers, but you can find a reasonable compromise pretty quickly. Once you do fairly well adjusting one shot, Lightroom enables you to copy your develop settings and apply them to additional photos.
There are other subtle tricks of course, but I save them for workshops.  Check the links at the top of the front page of this blog for upcoming dates.

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How To Create Star Trail Images

With today’s digital cameras it is surprisingly easy to create star trails photographs. At the highest level, all you do is run a sequence of night star shots through a star trails program and enjoy the result. As is often the case, the challenges come in the details.

You’ll need to capture images covering 30 to 60 minutes or more. A sturdy tripod is essential. You can trigger exposures manually, but that’s tedious and not fun to do for an hour at night. Ideally you’ll have a remote trigger that can lock down to fire off sequential shots, or even better, an intervalometer which takes shots at certain intervals which you define.

You’ll need to focus your lens on an object at infinity, and leave the focus mode set to manual so it won’t hunt for focus in the dark. The focus ring of your lens probably continues past that point to compensate for differences as temperatures fluctuate, so note where this is, or if your lens has continuous focus ring with no visible scale, focus your camera during the day, switch it into manual, and carefully tape the focus ring with removable painter’s masking tape.

You’ll want to take sequential shots close together so the star trails to be continuous, so turn off your camera’s long exposure noise reduction.

You’ll also want a consistent exposure, so put your camera in manual exposure mode.

Cameras have different sensitivity to light, and the moon phase and local light pollution can affect your exposure, so you’ll need to run some tests to determine what settings to use for your individual shots.

With no moon in perfectly dark skies I use f/2.8 at ISO 6400 for 30 seconds. Don’t have f/2.8 or ISO 6400? No problem, lengthen your exposure time. If you have f/4.0 and ISO 1600, you’ll double the time for the aperture and then another 4X for the two stop loss in sensitivity to 1600, so your exposure time could be 4 minutes. Your actual time will often be less due to some ambient light from the moon or light pollution. Take lighter and darker shots to ensure that you’ve identified an exposure which isn’t too bright or too dark.

Once you have the basic exposure figured out, take that exposure over and over until you reach 30 to 45 minutes or more total. Leave as little time as possible between shots.

For this example I used about 80 shots of 30 seconds each, covering 40 minutes. I used the free StarStaX software (www.StarStaX.net) in “lighten” mode, where the lightest pixels are kept as images are merged, creating the trails as the stars move from frame to frame.

Unfortunately in Yosemite Valley the cars driving by also create lasting light trails. To remove them, there’s also a “darken” mode which keeps the darkest pixels, eliminating the car headlights.

This also eliminates the star trails, but by using layers in Photoshop and blending that center portion of the darkened sequence into the lightened star trails sequence to get a star trails image without the car lights.

So what else can the free StarStaX software be used for?  You can use it for quickly and easily layering any landscape images where you want the brightest portions to come through, like bringing multiple lightning strikes into one image:

Go give it a try!

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