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Top picture: Floor lamp sliding back and forth; long exposure photography done right!

Bottom picture: Bug sweeper waved back and forth reveals microphone's capacity to eavesdrop. Loudspeaker emits a test tone, and a lock-in receiver picks up even the weakest of signal transmissions and outputs to an attached SWIM (Sequential Wave Imprinting Machine) that displays audio "metasensing" waveforms.

Long-exposure photography done right!

In this Instructable I present 8 simple steps you can use to mimic human vision and capture a true and accurate picture of a light source that is being waved back and forth.

The result is a sequence of exposures that can be combined (9th step) into a single .gif image that shows the back and forth motion nicely.

This is the sequence of steps I've developed over that past 42 years (originally back in the days of film, to make "flip books" of pictures that show light trails in long exposures of a linear array lights I made to see radio waves, sound waves, etc.).

Once you get the hang of it, it is quite quick and simple to do.

This method can then be applied to phenomenal augmented reality as in my previous Instructables.

Begin with a light source such as the augmented reality wand you made from one of my previous Instructables, or simply a light bulb or candle or anything else that glows.

For best results, use a camera with manual exposure settings.

A camera flash helps fill in the details, and you get a nice "flash and blur" effect. The following steps assume you have the more common first-curtain flash sync (you can easily adapt to second curtain sync if that is what you prefer).

Step 1: Begin

Locate a dark space where the lights can be turned off. Here we are using a light bulb in a dark classroom. Choose a dark black background ("blackground") for best results. Here the blackground is the blackboard. It can also be a large open dark space, or you can hang a "blackdrop" (e.g. a black backdrop cloth)....

Identify a beginpoint and an endpoint. Mark these with objects that the subject can easily see in the dark (e.g. see by only the light of the lamp), or by objects the subject can feel. Here we use the two ends of a chalkboard that the subject can feel by running his fingers along the chalk trough, in this example.

Here a camera on a tripod is set to "B" ("Bulb") and a remote control is used to activate it so as not to shake the camera: remote activation means we can actuate the shutter without pressing on any of its buttons which would shake it and perhaps make the exposures blurry or misaligned.

Before you turn off the lights to "Begin", you might want to take one or more pictures with the lights still on, and then turn the lights off and take one or more pictures of the dark (no flash) to characterize the ambient light in the scene. You can use these for advanced image processing (e.g. to model the background statistics of the light in the room, analogous to a "room tone" audio recording). I call these a1.jpg, a2.jpg, a3.jpg, ... ("Ambients").

Begin

Have the subject stand at the beginning position holding a light source. Here the subject is holding a light bulb plugged into a light dimmer and turned down really low. I like to use a reasonable size light bulb like a 750 watt, 1000 watt, or 1500 watt light bulb dimmed down to a really low brightness, so we can see the intricate details of a nicely sized bulb and nicely sized filament.

While the subject stands still, take a picture of the subject holding the light.

Sometimes I take multiple "Begins" and assign them filenames like b1.jpg, b2.jpg, b3.jpg and pick the best one, or use more than one if you want your exposure .gif file to ultimately "dwell" at the beginpoint for longer.

<p>Hey Steve, its Logan, made this last night was lots of fun. It's surprising how much a smartphone camera can do.</p>
<p>It doesn't seem to upload properly so here's a link: https://imgflip.com/gif/1l15jx</p>
<p>Made it in my residence.Hope it works.</p>
<p>Looks great.</p><p>You might want to try a more firm tripod for the camera mount to keep it steady.</p><p>Keep up the great work.</p><p>Steve</p>
<p>A floor lamp and two belts. Did it in my university residence. The belts always fell from the wall in the process :(</p><p>Lang Qian</p>
<p>Lang,</p><p>This is good to see you've figured out the Instructable and also it was fun working with you through email correspondence to solve the .gif file mystery.</p><p>It used to be that within in Instructable the .gif file size limit was 10,000,000 bytes exactly.</p><p>It appears that for comments, there might be a 5,000,000 byte limit.</p><p>Steve</p>
<p>The GIF will fail to animate when the size of it is too big although the website would say &quot;Upload Complete&quot; and give you no sign that it will not work.</p>
<p>According to my tests, the limit is around 5000 KB (not 5 MB). The gif with 4605 KB succeeded while the one with 5088 KB failed.</p>
<p>Test3</p>
<p>Test2</p>
<p>Test</p>
<p>A floor lamp and two belts. Did it in my university residence. The belts always fell from the wall in the process :(</p><p>Lang Qian</p>
<p>The belts could also form markers to indicate where to stop and end the sequence each time.</p><p>It is good to use some kind of marker at the beginning and end of the light trail, especially if you're relying on a speed of sound or speed of light calculation: you can measure the distance and use that in a calculation.</p>
<p>Wrote a welcoming 'TORONTO' sign with glowing sticks by using long exposure photography. An exciting and interesting activity to do. :)</p>
<p>That's very nice. I like the way you've applied the 8 steps of the Instructable to each of the letters separately. </p>
<p>Here is my long exposure photography of a remote-control-train going around a track</p>
<p>Nice to see this back and forth motion around a loop. I've got a slightly different version of abakography for things that go around in a loop rather than back-and-forth.</p><p>Keep up the great work!</p>
<p>This is a new way to learn the piano using Abakography animation. My roommate is a piano player and using abakography, we can capture information about his timing and exact movements.</p>
<p>This would be an interesting way to learn musical instruments or other activities....</p>
<p>Did the experiment with some sparklers, a very fun lab to do!</p>
<p>Very nice to see some alternate light sources!</p><p>Great work!</p>
<p>Here is my mvm. 9.8MB didn't seem to work, hopefully 5.6MB (960x643) works. </p>
<p>Looks great!</p><p>Keep up the good work.</p>
<p>Here is my animation.</p><p>The device on my bicycle wheel is a S.W.I.M. stick driven by an accelerometer + micro-controller, displaying the gravity values in a range from -1 to +1.</p>
<p>Its very nice to see this pattern, and also a good example of polar coordinates. We could also see polar plots of microphone sensitivities, etc..</p>
<p>I really like the idea of combining long exposure photography with GIF. I couldn't get my hands on a very high end camera but I gave it a shot. It was certainly nice to understand and experiment with different aperture and ISO settings to try and get the best contrast. Thanks for sharing.</p>

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Bio: I grew up at a time when technologies were transparent and easy to understand, but were evolving toward insanity and incomprehensibility. So I wanted to ... More »
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