How to Photograph the Great Conjunction


On December 21 we have a chance to see and shoot a celestial event that no one has seen since the year 1226. 

As Jupiter and Saturn each orbit the Sun, Jupiter catches up to slower moving Saturn and passes it every 20 years. For a few days the two giant planets appear close together in our sky. The last time this happened was in 2000, but with the planets too close to the Sun to see. 

Back on February 18, 1961 the two planets appeared within 14 arc minutes or 0.23° (degrees) of each other low in the dawn sky. 

But on December 21 they will pass each other only 6 arc minutes apart. To find a conjunction that close and visible in a darkened sky you have to go all the way back to March 5, 1226 when Jupiter passed only 3 arc minutes above Saturn at dawn. Thus the media headlines of a “Christmas Star” no one has seen for 800 years! 

Photographing the conjunction will be a challenge precisely because the planets will be so close to each other. Here are several methods I can suggest, in order of increasing complexity and demands for specialized gear. 


Easy — Shooting Nightscapes with Wide Lenses

This shows the field of view of various lenses on full-frame cameras (red outlines) and a 200mm lens with 1.4x tele-extender on a cropped frame camera (blue outline). The date is December 17 when the waxing crescent Moon also appears near the planet pair for a bonus element in a nightscape image.

Conjunctions of planets in the dusk or dawn twilight are usually easy to capture. Use a wide-angle (24mm) to short telephoto (85mm) lens to frame the scene and exposures of no more than a few seconds at ISO 200 to 400 with the lens at f/2.8 to f/4. 

The sky and horizon might be bright enough to allow a camera’s autoexposure and autofocus systems to work. 

Indeed, in the evenings leading up to and following the closest approach date of December 21 that’s a good method to use. Capture the planet pair over a scenic landscape or urban skyline to place them in context. 

For most locations the planets will appear no higher than about 15° to 20° above the southwestern horizon as it gets dark enough to see and shoot them, at about 5 p.m. local time. A 50mm lens on a full-frame camera (or a 35mm lens on a cropped frame camera) will frame the scene well. 

This was Jupiter and Saturn on December 3, 2020 from the Elbow Falls area on the Elbow River in the Kananaskis Country southwest of Calgary. This is a blend of 4 untracked images for the dark ground, stacked to smooth noise, for 30 seconds each, and one untracked image for the bright sky for 15 seconds to preserve colours and highlights, all with the 24mm Sigma lens and Canon EOS Ra at ISO 200.

NIGHTSCAPE TIP — Use planetarium software such as Stellarium (free), SkySafari, or StarryNight (what I used here) to simulate the framing with your lens and camera. Use that software to determine where the planets will be in azimuth, then use a photo planning app such as PhotoPills or The Photographer’s Ephemeris to plan where to be to place the planets over the scene you want at that azimuth (they’ll be at about 220° to 230° — in the southwest — for northern latitude sites). 

My ebook linked to at right has pages of tips and techniques for shooting nightscapes and time-lapses. 

This was Jupiter and Saturn on December 10, 2020 from Red Deer River valley, north of Drumheller, Alberta. This is a blend of 4 images for the dark ground, stacked to smooth noise, for 20 seconds each at f/5.6, and a single image for the sky for 5 seconds at f/2.8, all with the 35mm Canon lens and Canon EOS Ra at ISO 400. All untracked.

Harder — Shooting With Longer Lenses

The planet pair will sink lower and closer to the horizon, to set about 7:00 to 7:30 p.m. local time each night. 

As the sky darkens and the planet altitude decreases you can switch to ever-longer lenses to zoom in on the scene and still frame the planets above a carefully-chosen horizon, assuming you have very clear skies free of haze and cloud. 

For example, by 6 p.m. they will be low enough to allow a 135mm telephoto to frame the planets and still have the horizon in the frame. Using a longer lens has the benefit or resolving the two planets better, showing them as two distinct objects, which will become more of a challenge the closer you are to December 21. 

On December 21 wide-angle and even short telephoto lenses will likely show the two planets as an unresolved point of light, no brighter than Jupiter on its own.

On closest approach day the planets will be so close that using a wide-angle or even a normal lens might only show them as an unresolved blob of light. You’ll need more focal length to split the planets well into two objects. 

However, using longer focal lengths introduces a challenge — the motion of the sky will cause the planets to trail during long exposures, turning them from points into streaks. That trailing will get more noticeable more quickly the longer the lens you use. 

A rule-of-thumb says the longest exposure you can employ before trailing becomes apparent is 500 / the focal length of the lens. So for a 200mm lens, maximum exposure is 500 / 200 = 2.5 seconds. 

To be conservative, a “300 Rule” might be better, restricting exposures with a 200mm telephoto to 300 / 200 = 1.5 seconds. Now, 1.5 seconds might be long enough for the scene, especially if you use a fast lens wide open at f/2.8 or f/2 and a faster ISO such as 400 or 800. 

This shows the motion of Jupiter relative to Saturn from December 17 to 25, with the outer frame representing the field of view of a 200mm lens and 1.4x tele-extender on a cropped frame camera. The smaller frame shows the field of a telescope with an effective focal length of 1,200mm.

TELEPHOTO TIP — Be sure to focus carefully using Live View to manually focus on a magnified image of the planets. And refocus through an evening of shooting. While people fuss about getting the one “correct” exposure, it is poor focus that ruins more astrophotos. 


Even More Demanding — Tracking Longer Lenses 

This one popular sky tracker, the iOptron SkyGuider Pro, here with a telephoto lens. It and other trackers such as the Sky-Watcher Star Adventurer seen in the opening image, can be used with lenses and telescopes up to about 300mm focal length, if they are balanced well. Even longer lenses might work for the short exposures needed for the planets, but vibration and wind can blur images.

However, longer exposures might be needed later in the evening when the sky is darker, to set the planets into a starry background. After December 17 we will have a waxing Moon in the evening sky to light the sky and foreground, so the sky will not be dark, even from a rural site. 

Even so, to ensure untrailed images with long telephotos — and certainly with telescopes — you will need to employ a sky tracker, a device to automatically turn the camera to follow the sky. If you don’t have one, it’s probably too late to get one and learn how to use it! But if you have one, here’s a great opportunity to put it to use. 

Polar align it (you’ll have to wait for it to get dark enough to see the North Star) and then use it to take telephoto close-up images of the planets with exposure times that can now be as long as you like, though they likely won’t need to be more than 10 to 20 seconds. 

You can now also use a slower ISO speed for less noise. 

TRACKER TIP — Use a telephoto to frame just the planets, or include some foreground content such as a hilltop, if it can be made to fit in the frame. Keep in mind that the foreground will now blur from the tracking, which might not be an issue. If it is, take exposures of the foreground with the tracker motor off, to blend in later in processing. 


The Most Difficult Method — Using a Telescope

An alt-azimuth mounted GoTo scope like this Celestron SE6 can work for short exposures of the planets, provided it is aligned and is tracking properly. Good focus will be critical.

Capturing the rare sight of the planets as two distinct disks (not just dots of light) accompanied by their moons, all together in the same frame, is possible anytime between now and the end of the year. 

But … resolving the disks of the planets takes focal length — a lot of focal length! And that means using a telescope on a mount that can track the stars. 

While a sky tracker might work, they are not designed to handle long and heavy lenses and telescopes. You’d need a telescope on a solid mount, though it could be a “GoTo” telescope on an alt-azimuth mount. Such a mount, while normally not suited for long-exposure deep-sky imaging, will be fine for the short exposures needed for the planets.

You will need to attach your camera to the telescope using a camera adapter, so the scope becomes the lens. If you have never done this, to shoot closeups of the Moon for example, and don’t have the right adapters and T-rings, then this isn’t the time to learn how to do it.

A simulation of the view with a 1,200mm focal length telescope on December 21. Even with such a focal length the planet disks still appear small.

TELESCOPE TIP — As an alternative, it might be possible to shoot the planets using a phone camera clamped to the low-power eyepiece of a telescope, but focusing and setting the exposure can be tough. It might not be worth the fuss in the brief time you have in twilight, perhaps on the one clear night you get! Just use your telescope to look and enjoy the view! 

But if you have experience shooting the Moon through your telescope with your DSLR or mirrorless camera, then you should be all set, as the gear and techniques to shoot the planets are the same. 

This is the setup I might use for a portable rig best for a last-minute chase to clear skies. It’s a Sky-Watcher EQM-35 mount with a 105mm apo refractor (the long-discontinued Astro-Physics Traveler), and here with a 2x Barlow to double the effective focal length to 1,200mm.

However, once again the challenge is just how close the planets are going to get to each other. Even a telescope with a focal length of 1200mm (typical for a small scope) still gives a field of view 1° wide using a cropped frame camera. That’s 60 arc minutes, ten times the 6 arc minute separation of Jupiter and Saturn on December 21! 

TELESCOPE TIP — Use a 2x or 3x Barlow lens if needed to increase the effective focal length of the scope. Beware that introducing a Barlow into the light path usually requires racking the focus out and/or adding extension tubes to reach focus. Test your configuration as soon as possible to make sure you can focus it. 

TELESCOPE TIP — With such long focal lengths shoot lots of exposures. Some will be sharper than others. 

TELESCOPE TIP — But be sure to focus precisely, and refocus over the hour or so you might be shooting, as changing temperatures will shift the focus. You can’t fix bad focus! 

Jupiter and Saturn in the same telescope field on December 5, 2020. Some of the moons are visible in this exposure taken in twilight before the planets got too low in the southwest. This is a single exposure with a 130mm Astro-Physics apo refractor at f/6 (so 780mm focal length) for 4 seconds at ISO 200 with the Canon 6D MkII. The disks of the planets are overexposed to bring out the moons.

Short exposures under one second might be needed to keep the planet disks from overexposing. Capturing the moons of Jupiter (it has four bright moons) and Saturn (it has two, Titan and Rhea, that are bright) will require exposures of several seconds. Going even longer will pick up background stars.

Or … with DSLRs and mirrorless cameras, try shooting HD or 4K movies. They will likely demand a high and noisy ISO, but might capture the view more like you saw and remember it. 

FINAL TIP — Whatever combination of gear you decide to use, test it! Don’t wait until December 21 to see if it works, nor ask me if I think such-and-such a mount, telescope or technique will work. Test for yourself to find out.

Jupiter and Saturn taken in the deep twilight on December 3, 2020 from the Allen Bill flats area on the Elbow River in the Kananaskis Country southwest of Calgary, Alberta. This is a blend of 4 untracked images for the dark ground, stacked to smooth noise, for 2 minutes each at ISO 400, and two tracked images for the sky (and untrailed stars) for 30 seconds each at ISO 400, all with the 35mm Canon lens at f/2.8 and Canon EOS Ra. The tracker was the Sky-Watcher Star Adventurer 2i.

Don’t Fret or Compete. Enjoy! 

The finest images will come from experienced planetary imagers using high-frame-rate video cameras to shoot movies, from which software extracts and stacks the sharpest frames. Again, if you have no experience with doing that (I don’t!), this is not the time to learn! 

And even the pros will have a tough time getting sharp images due to the planets’ low altitude, even from the southern hemisphere, where some pro imagers have big telescopes at their disposal, to get images no one else in the world can compete with!

In short, use the gear you have and techniques you know to capture this unique event as best you can. And if stuff fails, just enjoy the view! 

Jupiter and Saturn taken December 3, 2020 from the Allen Bill flats area on the Elbow River in the Kananaskis Country southwest of Calgary, Alberta. This is a blend of 4 untracked images for the dark ground, stacked to smooth noise, for 2 minutes each at ISO 400, and two tracked images for the sky for 30 seconds at ISO 1600, all with the 35mm Canon lens at f/2.8 and Canon EOS Ra. The tracker was the Sky-Watcher Star Adventurer 2i.

If you miss closest approach day due to cloud, don’t worry. 

Even when shooting with telephoto lenses the photo ops will be better in the week leading up to and following December 21, when the greater separation of the planets will make it easier to capture a dramatic image of the strikingly close pairing of planets over an Earthly scene. 

Clear skies! 

— Alan, © 2020 AmazingSky.com 

Testing the MSM Tracker


MSM Test Title

A new low-cost sky tracker promises to simplify not only tracking the sky but also taking time-lapses panning along the horizon. It works but …

If you are an active nightscape photographer chances are your social media feeds have been punctuated with ads for this new low-cost tracker from MoveShootMove.com. 

For $200, much less than popular trackers from Sky-Watcher and iOptron, the SiFo unit (as it is labelled) offers the ability track the sky, avoiding any star trails. That alone would make it a bargain, and useful for nightscape and deep-sky photographers. 

But it also has a function for panning horizontally, moving incrementally between exposures, thus the Move-Shoot-Move designation. The result is a time-lapse movie that pans along the horizon, but with each frame with the ground sharp, as the camera moves only between exposures, not during them. 

 

MSM Polar Aligned Side V1
The Move-Shoot-Move Tracker
The $200 MSM can be polar aligned using the optional laser, shown here, or an optical polar scope to allow to follow the sky. The ball head is user supplied. 

Again, for $200 this is an excellent feature lacking in trackers like the Sky-Watcher Star Adventurer or iOptron SkyTracker. The Sky-Watcher Star Adventurer Mini does, however, offer both tracking and “move-shoot-move” time-lapse functions, but at a cost of $300 to $400 U.S., depending on accessories. 

All these functions are provided in a unit that is light (weighing 700 grams with a tripod plate and the laser) and compact (taking up less space in your camera bag than most lenses). By comparison, the Star Adventurer Mini weighs 900 grams with the polar scope, while the original larger Star Adventurer is 1.4 kg, double the MSM’s weight. 

Note, that the MSM’s advertised weight of 445 grams does not include the laser or a tripod plate, two items you need to use it. So 700 grams is a more realistic figure, still light, but not lighter than the competition by as much as you might be led to believe. 

Nevertheless, the MSM’s small size and weight make it attractive for travel, especially for flights to remote sites. Construction is solid and all-metal. This is not a cheap plastic toy.

But does it work? Yes, but with several important caveats that might be a concern for some buyers. 

What I Tested

I purchased the Basic Kit B package for $220 U.S., which includes a small case, a laser pointer and bracket for polar alignment (and with a small charger for the laser’s single 3.7-volt battery), and with the camera sync cable needed for time-lapse shooting. 

I also purchased the new “button” model, not the older version that used a knob to set various tracking rates. 

 

MSM with Canon 6D MkII
MSM Fitted Out
Keep in mind that to use any tracker like the MSM you will need a solid tripod with a head good enough to hold the tracker and camera steady when tipped over when polar aligned, and another ball head on the tracker itself.

The ball head needed to go on top of the tracker is something you supply. The kit does come with two 3/8-inch stud bolts and a 3/8-to1/4-inch bushing adapter, for placing the tracker on tripods in the various mounting configurations I show below. 

The first units were labelled as ‘SiFo,” but current units now carry the Gauda brand name. I’ll just call it the MSM. 

I purchased the gear from the MSM website, and had my order fulfilled and shipped to me in Canada from China with no problems. 

Tracking the Sky in Nightscapes

The attraction is its tracking function, allowing a camera to follow the sky and take exposures longer than any dictated by “500” or “NPF” Rules to avoid any star trailing. 

Exposures can be a minute or more to record much more depth and detail in the Milky Way, though the ground will blur. But blending tracked sky exposures with untracked ground exposures gets around that, and with the MSM it’s easy to turn on and off the tracking motor, something not possible with the low-cost wind-up Mini Track from Omegon. 

MSM Polar Aligned Side V2
Mounting on the Side
The MSM is shown in illustrations and instructions mounted by its side panel bolt hole. This works, but produced problems with the gears not meshing well and the MSM not tracking at all for initial exposures. 

The illustrations and instructions (in a PDF well-hidden off the MSM Buy page) show the MSM mounted using the 1/4-20 bolt hole on the side of the unit opposite the LED-illuminated control panel. While this seems to be the preferred  method, in the first unit I tested I found it produced serious mis-tracking problems. 

MSM Test (On Side) 1 minute 50mm
50mm Lens Set, Mounted on the Side
A set of five consecutive 1-minute exposures taken with the original SiFo-branded MSM mounted by its side bolt hole showed the MSM’s habit of taking several minutes for the gears to mesh and to begin tracking. Tap or click to download full-res version.

With a Canon 6D MkII and 50mm f/1.4 lens (not a particularly heavy combination), the MSM’s gears would not engage and start tracking until after about 5 minutes. The first exposures were useless. This was also the case whenever I moved the camera to a new position to re-frame the scene or sky. Again, the first few minutes produced no or poor tracking until the gears finally engaged. 

This would be a problem when taking tracked/untracked sets for nightscapes, as images need to be taken in quick succession. It’s also just plain annoying.

However, see the UPDATE at the end for the performance of a new Gauda-branded unit that was sent to me. 

Sagittarius - Red Enhancer Filter
50mm Nightscape
With patience and persistence you can get well-tracked nightscapes with the MSM. This is a single 1-minute exposure with a 50mm lens. Tap or click to download full-res version.

Mounting Options

The solution was to mount the MSM using the 3/8-inch bolt hole on the back plate of the tracker, using the 1/4-20 adapter ring to allow it to attach to my tripod head. This still allowed me to tip the unit up to polar align it. 

MSM Polar Aligned Back V1
Mounting on the Back
Mounting the MSM using its back plate produced more reliable tracking results, though requires swapping mounting bolts and 3/8-1/4-inch adapter rings from the preferred method of mounting the MSM for time-lapse work. 

Tracking was now much more consistent, with only the first exposure usually badly trailed. But subsequent exposures all tracked, but with varying degrees of accuracy as I show below. 

When used as a tracker, you need to control the camera’s exposure time with an external intervalometer you supply, to allow setting exposures over 30 seconds long. 

The MSM offers a N and S setting, the latter for use in the Southern Hemisphere. A 1/2-speed setting turns the tracker at half the normal sidereal rate, useful for nightscapes as a compromise speed to provide some tracking while minimizing ground blurring. 

Polar Alignment

For any tracker to track, its rotation axis has to be aimed at the Celestial Pole, near Polaris in the Northern Hemisphere, and near Sigma Octantis in the Southern Hemisphere. 

MSM Tracker with Laser Pointer (Red Light Version)
Polar Aligning on Polaris
The MSM’s bright laser pointer is useful for aiming the tracker at the North Celestial Pole, located about a degree away from Polaris in the direction of Alkaid, the end star in the Handle of the Big Dipper or Plough. 

I chose the laser pointer option for this, rather than the polar alignment scope. The laser attaches to the side of the MSM using a small screw-on metal bracket so that it points up along the axis of rotation, the polar axis. 

The laser is labeled as a 1mw unit, but it is far brighter than any 1mw I’ve used. This does make it bright, allowing the beam to show up even when the sky is not dark. The battery is rechargeable and a small charger comes with the laser. Considering the laser is just a $15 option, it’s a bargain. But ….


UPDATE ADDED SEPTEMBER 1

Since I published the review, I have had the laser professionally tested, and it measured as having an output of 45 milliwatts. Yet it is labeled as being under 1 milliwatt. This is serious misrepresentation of the specs, done I can only assume to circumvent import restrictions. In Canada it is now illegal to import, own, or use any green laser over 5 milliwatts, a power level that would be sufficient for the intended use of polar aligning. 45mw is outright illegal. 


So be warned, use of this laser will be illegal in some areas. And use of any green laser will be illegal close to airports, and outlawed entirely in some jurisdictions such as Australia, a fact the MSM website mentions. 

The legal alternative is the optical polar alignment scope. I already have several of those, but my expectation that I could use one I had with the same bracket supplied with the laser were dashed by the fact that the bracket’s hole is too narrow to accept any of the other polar alignment scopes I have, which are all standard items. I you want a polar scope, buy theirs for $70. 

However, if you can use it where you live, the laser works well enough, allowing you to aim the tracker at the Pole just by eye. For the wide lenses the tracker is intended to be used with, eyeball alignment proved good enough.

Just be very, very careful not to accidentally look down the beam. Seriously. It is far too easy to do by mistake, but doing so could damage your eye in moments. 

Tracking the Sky in Deep-Sky Images

How well does the MSM actually track? In tests of the original SiFo unit I bought, and in sets of exposures with 35mm, 50mm, and 135mm lenses, and with the tracker mounted on the back, I found that 25% to 50% of the images showed mis-tracking. Gear errors still produced slightly trailed stars. This gear error shows itself more as you shoot with longer focal lengths. 

MSM Test (On Back) 2 min 35mm
35mm Lens Set, Mounted on the Back
A set of 2-minute exposures with the MSM mounted by its back plate showed better tracking with quicker gear meshing, though still with some frames showing trailing. Tap or click to download full-res version.

The MSM is best for what it is advertised as — as a tracker for nightscapes with forgiving wide-angle lenses in the 14mm to 24mm range. With longer lenses, expect to throw away a good number of exposures as unusable. Take twice as many as you think you might need.

MSM Test (On Back) 1 min 135mm
135mm Telephoto Lens Set
A set of 20 one-minute exposures with a 135mm lens showed more than half with unusable amounts of mis-tracking. But enough worked to be usable! Tap or click to download full-res version.

With a 135mm lens taking Milky Way closeups, more than half the shots were badly trailed. Really badly trailed. This is not from poor polar alignment, which produces a gradual drift of the frame, but from errors in the drive gears, and random errors at that, not periodic errors. 

To be fair, this is often the case with other trackers as well. People always want to weight them down with heavy and demanding telephotos for deep-sky portraits, but that’s rarely a good idea with any tracker. They are best with wide lenses.

That said, I found the MSM’s error rate and amount to be much worse than with other trackers. With the Star Adventurer models and a 135mm lens for example, I can expect only 20% to 25% of the images to be trailed, and even then rarely as badly as what the MSM exhibited.

See the UPDATE at the end for the performance of the replacement Gauda-branded unit sent to me with the promise of much improved tracking accuracy. 

The Arrow, Dumbbell, and Coathanger
Sagitta and Area with the 135mm
The result of the above set was a stack of 8 of the best for a fine portrait of the Milky Way area in Sagitta, showing the Dumbbell Nebula and Coathanger asterism. Each sub-frame was 1 minute at f/2 and ISO 1600. Tap or click to download full-res version.

Yes, enough shots worked to be usable, but it took using a fast f/2 lens to keep exposure times down to a minute to provide that yield. Users of slow f/5.6 kit-zoom lenses will struggle trying to take deep-sky images with the MSM. 

In short, this is a low-cost tracker and it shows. It does work, but not as well as the higher-cost competitors. But restrict it to wide-angle lenses and you’ll be fine. 

Panning the Ground 

The other mode the MSM can be used in is as a time-lapse motion controller. Here you mount the MSM horizontally so the camera turns parallel to the horizon (or it can be mounted vertically for vertical panning, a mode I rarely use and did not test). 

MSM Tracker Taking Time-Lapse in Moonlight
The MSM at Work
I performed all the time-lapse testing from my rural backyard on nights in mid-August 2019 with a waning Moon lighting the sky. 

This is where the Move-Shoot-Move function comes in. 

The supplied Sync cable goes from the camera’s flash hot shoe to the MSM’s camera jack. What happens is that when the camera finishes an exposure it sends a pulse to the MSM, which then quickly moves while the shutter is closed by the increment you set.

There is a choice of 4 speeds, marked in degrees-per-move: 0.05°, 0.2°, 0.5°, and 1.0°. For example, as the movie below shows, taking 360 frames at the 1° speed results in a complete 360° turn.

 

MSM Control Panel CU
Time-Lapse Speeds
The control panel offers a choice of N and S rotation directions, a 1/2-speed rate for partially tracked nightscapes, and Move-Shoot-Move rates per move of 0.05°, 0.2°, 0.5° and a very fast 1° setting. The Sync cable plugs into the jack on the MSM. The other jack is for connecting to a motion control slider, a function I didn’t test.

The MSM does the moving, but all the shutter speed control and intervals must be set using a separate intervalometer, either one built into the camera, or an outboard hardware unit. The MSM does not control the camera shutter. In fact, the camera controls the MSM.

Intervals should be set to be about 2 seconds longer than the shutter speed, to allow the MSM to perform its move and settle. 

This connection between the MSM and camera worked very well. It is unconventional, but simple and effective.

MSM Time-Lapse Correct
Mounting for Time-Lapse
The preferred method of mounting the MSM for time-lapses is to do so “upside-down” with its rotating top plate at bottom attached to the tripod. Thus the whole MSM and camera turns, preventing the Sync cable from winding up during a turn. 

Too Slow or Too Fast

The issue is the limited choice of move speeds. I found the 0.5° and 1° speeds much too fast for night use, except perhaps for special effects in urban cityscapes. Even in daytime use, when exposure times are very short, the results are dizzying, as I show below. 

Even the 0.2°-per-move speed I feel is too fast for most nightscape work. Over the 300 exposures one typically takes for a time-lapse movie, that speed will turn the MSM (300 x 0.2°) = 60 degrees. That’s a lot of motion for 300 shots, which will usually be rendered out at 24 or 30 frames per second for a clip that lasts 10 to 12 seconds. The scene will turn a lot in that time.

On the other hand, the 0.05°-per-move setting is rather slow, producing a turn of (300 x 0.05°) = 15° during the 300 shots. 

That works, but with all the motion controllers I’ve used — units that can run at whatever speed they need to get from the start point to the end point you set — I find a rate of about 0.1° per move is what works best for a movie that provides the right amount of motion. Not too slow. Not too fast. Just right. 

MSM Time-Lapse Correct CU
Inverted Control Panel
When mounted as recommended for time-lapses, the control panel does end up upside-down. 


UPDATE ADDED DECEMBER 21, 2019

From product photos on the MoveShootMove.com website now it appears that the tracker is now labeled MSM, as it should have been all along.

Most critically, perhaps in response to this review and my comments here, the time-lapse speeds have been changed to 0.05, 0.075, 0.1 and 0.125 degrees per move, adding the 0.1°/move speed I requested below and deleting the overly fast 0.5° and 1.0° speeds.

Plus it appears the new units have the panel labels printed the other way around so they are not upside down for most mounting situations.

I have not tested this new version, but these speeds sound much more usable for panning time-lapses. Bravo to MSM for listening! 

MSM Rotator 2019


Following the Sky in a Time-Lapse

The additional complication is trying to get the MSM to also turn at the right rate to follow the sky — for example, to keep the galaxy core in frame during the time-lapse clip. I think doing so produces one of the most effective time-lapse sequences. 

But to do that with any device requires turning at a rate of 15° per hour, the rate the sky moves from east to west.

Because the MSM provides only set fixed speeds, the only way you have of controlling how much it moves over a given amount of time, such as an hour, is to vary the shutter speed. 

I found that to get the MSM to follow the Milky Way in a time-lapse using the 0.05° rate and shooting 300 frames required shooting at a shutter speed of 12 seconds. No more, no less. 

MSM Time-Lapse Top Plate
Top Plate Display
When mounted “upside-down” for a time-lapse the top surface provides the N-S direction arrows (N moves clockwise) and a small, handy bubble level.

Do the Math

Where does that number come from? 

At its rate of 0.05°/move, the MSM will turn 15° over 300 shots. The sky moves 15° in one hour, or 3600 seconds. So to fit 300 shots into 3600 seconds means each shot has to be no longer than (3600/300) = 12 seconds long. 

The result works, as I show in the sampler movie. 

But 12 seconds is a rather short shutter speed on a dark, moonless night with the Milky Way. 

For properly exposed images you would need to shoot at very fast apertures (f/1.4 to f/2) and/or high and noisy ISO speeds. Neither are optimal. But they are forced upon you by the MSM’s restricted rates. 

Using the faster 0.2° rate (of the original model) yields a turn of 60° over 300 shots. That’s four hours of sky motion. So each exposure now has to be 48 seconds long for the camera to follow the sky, four times longer because the drive rate is now four times faster. 

A shutter speed of 48 seconds is a little too long in my opinion. Stars in each frame will trail. Plus a turn of 60° over 300 shots is quite a lot, producing a movie that turns too quickly. 

MSM Time-Lapse Inverted
Alternative Time-Lapse Configuration
The other option is to mount the MSM so the control panel is right-side-up and the top turn-table (the part that turns and that the camera is attached to) is on top. Now only the camera turns; the MSM does not. This works but the Sync cable can wrap around and bind in long turns. For short turns of 30° to 60° it is fine. 

By far the best speed for motion control time-lapses would be 0.1° per move. That would allow 24-second exposures to follow the sky, allowing a stop less in aperture or ISO speed.  (DECEMBER 21 UPDATE: That speed seems to now be offered.)

Yes, having only a limited number of pre-wired speeds does make the MSM much easier to program than devices like the Star Adventurer Mini or SYRP Genie Mini that use wireless apps to set their functions. No question, the MSM is better suited to beginners who don’t want to fuss with lots of parameters. 

As it is, getting a decent result requires some math and juggling of camera settings to make up for the MSM’s limited choices of speeds. 

Time-Lapse Movie Examples

This compilation shows examples of daytime time-lapses taken at the fastest and dizzying 0.5° and 1.0° speeds, and night time-lapses taken at the slower speeds. The final clip is taken at 0.05°/move and with 12-second exposures, a combination that allowed the camera to nicely follow the Milky Way, albeit at a slow pace. Taking more than the 300 frames used here would have produced a clip that turned at the same rate, but lasted longer. 

Battery Life

The MSM is powered off an internal rechargeable battery, which can be charged from any 5-volt charger you have from a mobile phone. 

The MSM uses a USB-C jack for the power cable, but a USB-A to USB-C cord is supplied, handy as you might not have one if you don’t have other USB-C devices. 

The battery lasted for half a dozen or more 300-shot time-lapses, enough to get you through at least 2 or 3 nights of shooting. However, my testing was done on warm summer nights. In winter battery life will be less. 

While the built-in battery is handy, in the field should you find battery level low (the N and S switches blink as a warning) you can’t just swap in fresh batteries. Just remember to charge up before heading out. Alternatively, it can be charged from an external 5V battery pack such as used to prolong cell phone life. 

Hercules and Corona Borealis (50mm 6D)
The constellations of Hercules and Corona Borealis in the northern spring and summer sky. This is a stack of 3 x 2-minute exposures with the 50mm Sigma lens at f/2.8 and Canon 6D at ISO 800, plus an additional 2 min exposure through the Kenko Softon filter to add the star glows. All tracked on the original MSM SiFo Tracker from China. Tap or click to download full-res version.

Other Caveats

The MSM does not offer, nor does it promise, any form of automated panorama shooting. This is where the device turns by, say, 15° to 45° between shots, to shoot the segments for a still-image panorama. More sophisticated motion controllers from SYRP and Edelkrone offer that function, including the ability to mate two devices for automated multi-tier panoramas. 

Nor does the MSM offer the more advanced option of ramping speeds up and down at the start and end of a time-lapse. It moves at a constant rate throughout. 

While some of the shortcomings could perhaps be fixed with a firmware update, there is no indication anywhere that its internal firmware can be updated through the USB-C port. 

MSM Polar Aligned On Back


UPDATE ADDED OCTOBER 7, 2019

Since I published the review, MSM saw the initial test results and admitted that the earlier units like mine (ordered in June) exhibited large amounts of tracking error. They sent me a replacement unit, now branded with the Gauda label. According to MSM it contains a more powerful motor promised to improve tracking accuracy and making it possible to take images with lenses as long as 135mm.

I’m sorry to report it didn’t.

MSM Gauda-135mm Back-NE
This shows 300% blow-ups of a star field rising in the northeast sky taken with the new Gauda unit and with a 135mm lens, each for 2 minutes in quick succession. Less than 50% of the frames were useable and untrailed. (The first frames were shot through high clouds.)

MSM Gauda-135mm Back-Zenith
Taken the same night as the previous set, this shows 24 shots taken in quick succession with the same 135mm lens for 2 minutes each but with the camera aimed overhead to the zenith. None of the images were usable. All were trailed, most very badly.

In tests with the 135mm lens the new, improved MSM still showed lots of tracking error, to the point that images taken with a lens as long as this were mostly unusable.

Tap or click on the images to download full-res versions.

The short movie above takes the full-frame images from the zenith set of 24 frames taken over 48 minutes and turns them into a little time-lapse. It shows how the mechanism of the MSM seems to be wobbling the camera around in a circle, creating the mis-tracking.

Comparison with the Star Adventurer

As a comparison, the next night I used a Sky-Watcher Star Adventurer (the full-size model not the Mini) to shoot the same fields in the northeast and overhead with the same 135mm lens and with the same ball-head, to ensure the ball-head was not at fault. Here are the results:

Star Adventurer-135mm-NE
The same field looking northeast, with 300% blow-ups of 2-minute exposures with the 135mm lens and Star Adventurer tracker. As is usual with this unit, about 20% of the frames show mis-tracking, but none as badly as the MSM.

Star Adventurer-135mm-Zenith
Aiming the camera to the zenith the Star Adventurer again showed a good success rate with a slightly greater percentage trailed, but again, none as badly as the MSM.

The Star Adventurer performed much better. Most images were well-tracked. Even on those frames that showed trailing, it was slight. The Star Adventurer is a unit you can use to take close-ups of deep-sky fields with telephoto lenses, if that’s your desire.

By contrast, the MSM is best used — indeed, I feel can only be used practically — with wide-angle lenses and with exposures under 2 minutes. Here’s a set taken with a 35mm lens, each for 2 minutes.

MSM Gauda-35mm Side-NE
This is a set of consecutive 2-minute exposures with a 35mm lens and Canon 6D MkII on the MSM tracker, with the tracker mounted using the side 1/4-20 bolt hole. It was aimed to the northeast. About half the images showed significant trailing.

With the more forgiving 35mm lens, while more images worked, the success rate was still only 50%.

What I did not see with the new Gauda unit was the 5-minute delay before the gears meshed and tracking began. That issue has been resolved by the new, more powerful motor. The new Gauda model does start tracking right away.

But it is still prone to significant enough drive errors that stars are often trailed even with a 35mm lens (this was on a full-frame Canon 6D MkII).


UPDATED CONCLUSIONS (December 21, 2019)

The MSM tracker is low-cost, well-built, and compact for easy packing and travel. It performs its advertised functions well enough to allow users to get results, either tracked images of the Milky Way and constellations, or simple motion-control time-lapses. 

But it is best used — indeed I would suggest can only be used — with wide-angle lenses for tracked Milky Way nightscapes. Even then, take more shots than you think you need to be sure enough are well-tracked and usable. 

It can also be used for simple motion-control time-lapses, provided you do to the math to get it to turn by the amount you want, working around the too-slow or too-fast speeds. The new 0.1° per move speed (added in models as of December 2019) seems a reasonable rate for most time-lapses. 

However, I think aspiring time-lapse photographers will soon outgrow the MSM’s limitations for motion-control sequences. But it can get you started. 

If you really value its compactness and your budget is tight, the MSM will serve you well enough for tracked nightscape shooting with wide-angle lenses.

But if you wish to take close-ups of starfields and deep-sky objects with longer lenses, consider a unit like the Sky-Watcher Star Adventurer for its lower tracking errors. Or the Star Adventurer Mini for its better motion-control time-lapse functions. 

— Alan Dyer / August 22, 2019 / UPDATED October 7, 2019 / © 2019 AmazingSky.com

 

Autumn Stars Rising over Dinosaur Park


Autumn Sky Rising over Badlands

The autumn constellations rise into a colourful sky at Dinosaur Provincial Park, Alberta.

Last night the sky started out beautifully clear but as it got darker it was apparent even to the eye that the sky wasn’t really dark, despite the lack of any Moon.

The camera captured the culprit – extensive green airglow, to the east at right. A faint aurora also kicked up to the north, at left, adding a red glow. Light pollution from gas plants nearby and from Brooks 50 km away added yellow to the sky scattered off haze and incoming cloud.

The sky colours added to the scene of the autumn constellations of Cassiopeia, Andromeda, Perseus and Pegasus rising in the east. The Andromeda Galaxy is at centre. The Pleiades is (are?) just rising over the hill.

This is a composite of five stacked and tracked exposures for the sky (with the camera on the Star Adventurer tracking mount) and four stacked but untracked exposures I took at the end of the sequence for the sharp ground (I just turned the tracker motor off for these).

– Alan, September 26, 2014 / © 2014 Alan Dyer

 

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