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I took a timelapse of the 21 Aug 2017 solar eclipse. I did not have the ability to track the suns movement so every ~15 minutes I adjusted the camera position.

I want to create a timelapse that emulates tracking. Essentially I want to "cut" the sun out of each individual frame and stitch together where the only movement is the moon across the sun (as opposed to the sun across the frame). I just don't know where to begin.

Are there any automation tools that are designed for this purpose?

Thanks to the community in advance!

  • The sun does not move. ( in the context of your question ) the earth orbits the sun while it spins on its axis giving us on earth the appearance of the sun moving. Technically the sun and its solar system and the Galaxy move as a unit within the universe as the universe expands but that is not relevant to the question of knowing the relationship of the earths movement around the sun for photographing eclipses. I know you're asking about photo editing but someone may read this and think the sun is moving. – Alaska Man Aug 27 '17 at 20:55
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This can be done with most video editing software with an aptly-named feature called tracking. It does not always work perfectly but can be very effective and should be quite accurate for your purpose.

First you will need to create your time-lapse as usual. The sun will move across the frame with jumps for every time you moved the camera. Once you have your time-lapse, load into a video edition S/W.

With the tracking tool, select the object to track - in your case the sun - and let the process run. It will take several minutes, producing a track of control-points and the video will be anchored to those. Play the video to see where it lose tracking and, if so, adjust the control-points manually. The intermediate points will automatically follow for smooth tracking.

It is possible that each time you moved the camera, software tracking will stop. In that case, you must run the tracking tool again from the first frame where tracking is lost. Repeat as needed until the video is smooth.

  • Thanks Itai. I'm a novice with this stuff and use FCPX on occasion. I've been searching but not finding a tracking tool. Is it called something else? There are some "motion tracking" plugins (TrackX) but they seem to track across the frame for the purpose of attaching text (for example). This may help in my case but I don't know enough about this. – Jibran Aug 27 '17 at 18:58
  • When it is not called tracking, it would be called stabilize. Works exactly the same, choose a point to stabilize and it will be in the same position on all frames. We used to do demos with surfers surfing and its pretty cool. – Itai Aug 27 '17 at 19:57
  • I'll look into stabilize more. I downloaded the TrackX plugin and they have an effect called Track and LockDown, which is exactly what I needed. After it's done tracking it gives you an option to lock down either X or Y motion or both. Super cooool! Thanks for the help. Here's a ~100 frame sample: vimeo.com/231296861. – Jibran Aug 27 '17 at 20:26
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Don't know if there are automatic tools that would work - DSO stacking programs expect to track several stars, planetary stacking ones expect similar planetary detail, so something like an eclipse probably isn't going to work too well with either type.

However, it should be fairly easy to do by hand in something like photoshop (or any editor that allows multiple movable layers with variable transparency).

Just load the first picture in, move the sun to a central position, then repeat the following:

-load the next picture in as a new layer on top of the existing ones.

-make the new layer partially transparent (so you can see the layer underneath) then move it so the sun is in the same position as the layer underneath.

-make the new layer fully opaque again

When you've done that for each picture, you should have a set of separate layers that line up.

Now, you can go through and make each layer visible on its own, and save the results. This will give you a set of aligned frames that you can make your timelapse animation from.

  • Some good ideas here. Thanks for the quick response. I might lose my mind though with ~1300 images! – Jibran Aug 26 '17 at 23:36
  • Hadn't realised you had that many :). If you write your own code, the free openCV (Computer vision) library has a template matching function that finds the position of one template image in another image - don't know how well that would cope with a changing sun shape though - or you could just look for the top and bottom positions of very bright (sun) pixels, along with the leftmost or rightmost position of very bright (sun) pixels (depending on which side is clear of the moon) and work out how to align them that way. – JerryTheC Aug 26 '17 at 23:56
  • Yeah sorry... should have mentioned that. ;) Interesting idea. If I represented the sun geometrically (circle) I would know it's center position and radius and could crop it the same each time. Will need to brush up on my C++. – Jibran Aug 27 '17 at 0:28

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