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What's New

April 2014 - CamRanger is now capable of controlling StackShot!

January 2014 - Don't want to build a Water Drop Stand? Check this out.

June 2013 - Check out the StopShot Studio - a 12 channel computer controlled version of StopShot

April 2013, Capture insects in flight with our new portable Insect Rig.

January 2013 - Check out our new Water Valve Mounting Bracket for multiple colored collisions

December 2012 - Introducing the Shutter Support System. Completely portable high speed.

October 2012 - Check out our latest one of a kind product - the High Speed Shutter - finally you can capture insects in flight.

August 2012 - Take your StackShot into the field with our new Controller Carrier Also works great with StopShot.

February 2012 - See our new web page on creating Three Drop Collisions with StopShot.

January 2012 - Check out our latest sensor the RangeIR. Designed for birds and wildlife.

What type of Photography Do You Want to Do?
Cross Beam Sensor

 

High Speed How To:

Some General High Speed Stuff

The Process. Most of the pictures and techniques you see on this site were taken with traditional high speed photography methods. That is the shutter is left open in a dark room and the flash is used to expose the picture. Once the picture has been exposed the shutter is then closed. Some exceptions to this are Wildlife and insect photos, in this type of photography the shutter is generally controlled by StopShot. The downside of this is the shutter lag introduced by the camera. This lag can be up to 150mS making some shots more difficult than others.

The Flash. Why do we use a flash? Why can't you use the shutter to capture "high speed" events? Let's consider an example: Say you are trying to capture a pellet moving at 500ft/s. If you used a shutter speed of 1/1000 (fairly fast as far as shutters go) the shutter would be open for 1ms. In this amount of time the pellet would travel about 6 inches. This would make for a very streaky and blurry pellet. Now, if we use a flash that has adjustable power we can set the flash to give us a burst of light that only lasts about 50us. Now the pellet travelling at 500ft/s would travel only about 0.3 inches. With this flash duration we are able to capture very fast events and keep them in focus. See some of our example pictures to get a feel for what is possible.

Choosing a flash. Some care is required when selecting a flash for high speed photography. Almost any flash will work for capturing slower events like a single water drop. But a flash with a much shorter on time will be required to capture faster events like ballistics or drop collisions. Ideally the flash will have an adjustable power level. This will allow you more flexibility in the duration of flash and in adjusting your aperture for different depth of field effects. Some flashes are equipped with photo sensors that measure the light and turn off the flash when the exposure is correct. You can make the duration of the flash shorter with one of these flashes by putting a reflective surface in front of the flash and reflecting some of the light back to the light sensor.

A Word of Caution. Something to watch out for when using an older flash is high voltage on the hot shoe. High voltage flashes are not compatible with StopShot. The high voltage will not damage StopShot but the flashes will not trigger correctly. To find out more about high voltage flashes visit this page. The author of this page has done an excellent job of compiling a list of flashes and measured voltages on the hot shoe. He also has a section on how to measure your flash if you are so inclined (Be careful!! some flashes have very high voltages on them). If the voltage on your hot shoe is less than 40V it will work fine with StopShot. Cognisys is currently developing a high speed flash that is fully adjustable and specifically suited for high speed photography.