High Speed Photography Concept

This is going to be a very long post. But if you want to take high-speed photos, you need to understand the concept first.

Ok, I was asked about how to take pictures of the balloon popping. When I told them I used 2 sec shutter speed. They were like "2 sec? Serious?". Yes, I'm serious.

So let me explain the concept of High Speed Photography.

1) First of all, do you know what photography means?

Photography is originally a greek word so it has the same meaning in greek. It consists of two words put together. "photo" which derives from "phos" and it means "light" in english, and graphy,which probably derives from graphi , which can mean drawing. The exact form in greek is φωτογραφία (fotografia) So without light, you can't draw. Even when you open your shutter for 30secs in a totally dark room, your picture will still come out pitch-black. On the other hand, when it's bright enough, you can take a sharp/clear picture even at 1/4000 sec!

2)High speed vs Full flash

High speed photography is similar to full flash photography. Full flash photography means the object in the pictures you take are all illuminated with the light. Imagine/experiment that you are in a total dark room and I mean TOTAL darkness. Set your camera on a tripod and place an object in front of it. Then set your shutter speed to 30secs. After you take your shot, what you will see is a total black picture in your LCD screen. Then take another picture with the same setting. But this time, flash your speedlite towards the object when the shutter is open. Now, what you'll see in your camera LCD screen is the object which is illuminate by the flash.

Why does this happen? Because the camera only "sees" object that is bright. Same concept for using the film.

3) Flash power and Flash duration

In high speed photography, since all the light are from the flash, the actual shutter is the flash duration!

Here is some data on the 580ex ii's flash duration. source: http://www.rodandcone.com/2008/05/flash-durations-for-canon-580ex-ii-and.html As you can see, the higher the flash power, the longer the flash duration.

Canon 580EX II -- Distance from Flash to Sensor: 2 feet
1/128 power = 1/10714 seconds Flash Duration
1/64 power = 1/7894 seconds
1/32 power = 1/5464 seconds
1/16 power = 1/3785 seconds
1/8 power = 1/2650 seconds
1/4 power = 1/1716 seconds
1/2 power = 1/1017 seconds
Full power = 1/177 seconds

So, when u shoot at 1/128 power on the 580EX II, the actual shutter speed is 1/10714sec! Well e need high shutter speed for shooting high speed photography like balloon popping, don't we?

That's most of all you need to know about high speed photography. Stay tuned for the next post- How to take high speed photos!