TPB #90 – Analyzing Error in the Projectile Sensor

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The error of the Camera Axe’s projectile sensor is analyzed. Experiments are done in software to isolate the error which turns out to come almost entirely from the 4 microsecond granularity of the Camera Axe’s timer hardware. Then math is done on that 4 microsecond granularity to determine how that affects the reported speed of the bullet in the Camera Axe and the positioning of the bullet in a photo.

For a ...

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TPB #86 – Adjusting the Airgap Flash’s Voltage/Brightness

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This video shows how to adjust the the brightness of the airgap flash by adjusting its internal voltage. Make sure you know how to safely handle high voltage before attempting this.

* Projectile Photography with the Airgap Flash
* Airgap Flash User Manual
* Buy the Airgap Flash here

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TPB #83 – Improved Laser Trigger

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I show how to use a few dollars in parts from your local hardware store to improve a laser trigger on the Camera Axe. I basically use some PVC parts to create mounts for the laser and light sensors. This makes them weather proof, easy to mount on a tripod, and easier to align due to a diffuser in front of the light sensor. http://www.cameraaxe.com

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TPB #74 – Air Cannon

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In this video I describe how to take photos of flying ball bearings shot from an air cannon. I also go over the different energies in this versus an air pellet, and how that kinetic energy gets distributed into the target.

UPDATE: Alan pointed out my energy calculations were off by a few orders of magnitude and wikipedia confirmed it (http://en.wikipedia.org/wiki/Joule). The units for Joules are kg*(m^2)*(s^2). My units were g*(m^2)*(s^2). So to ...

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TPB #73 – What Water Droplets Do Under the Surface

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In this video I show what water droplets do under the surface when they splash into the liquid reservoir by using a clear glass reservoir. I show what happens with one drop and then two drops. This explains a lot about what’s happening and why two drops are required for those really tall water spouts.

See http://www.cameraaxe.com/ for more information about the Camera Axe.

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TPB #68 – A Projectile Photographing Rig

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This video shows you how I setup a space to photograph moving bullets. Then I show you some photos of exploding Christmas bulbs filled with gelatin.

Check out Alan’s flickr page

Camera Axe

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TPB #67 – New Airgap Flash

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[Update: The insurance company I was working with changed their mind after giving me a preliminary quote (I had thought it was finalized). Without the liability issuance I actually won’t be selling these. Feel free to contact me and get on a list if that changes, but at this time I’m not actually able to sell this device.]

This video introduces the new Airgap flash we’ve been working on for over a year. ...

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TPB #55 – Three Questions Related to Shutters

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This episode describes how a shutter works and answers the three questions related to shutter lag, high speed two curtain shutters, and high speed flash sync.

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TPB #44 – High Speed LED Flashes

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This week’s video is about very high speed flashes and whether LED based flashes are practical at these speeds. The dominant flash in this space is the air-gap flash with it’s half microsecond flash duration it is about 100 times faster than a typical speedlite flash from Canon or Nikon. I do some calculations that try to figure out how many LEDs you would need, what kind of current you’d need to driver ...

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TPB #42 – Do Optical Slave Flashes Work with High Speed Photos

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In this week’s video I look at the lag introduced by using a master flash to optically trigger a slave flash. Then I look at this extra lag and see how that would impact some common high speed photography cases like photographing a moving bullet and water droplets.

* Video about measuring Flash Lag
* Video about measuring Flash Duration
* Video about the MultiFlash board

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