Highspeed photography 101 – Lesson 2

Highspeed Photography 101

Table of contents

Introduction
Lesson 1: Freeze the motion with your shutter
Lesson 2: Freeze the motion with your shutter II
Lesson 3: Freeze the motion with your flash
Lesson 4: A small but powerful helper: Arduino
Lesson 5: Trigger your camera with an Arduino
Lesson 6: Trigger your flash with an Arduino
Lektion 7: Working with sensors: Light barrier
Lektion 8: Working with sensors: Sound trigger

Lesson 2: Freeze the motion with your shutter II

Introduction
In Lesson 1 we saw that the main problem with short shutter speeds is that you haven’t enough light. Lets have a look what happens if we use a flash.

Highspeed 101 - Lesson 2

Stuff needed
– Camera
– Flash with high speed sync

Technique
We saw that we need short shutter speeds to freeze the motion. As already mentioned, we will use a flash to get enough light. And this is already the problem, to get the flash working ‘correctly’ we need to have a flash which supports high speed synchronization. Mark Wallace has a great video (below) which explains what exactly high speed synchronization is.

There are different variants of high speed sync, therefore it is important to check that the flash is compatible with the cams high speed sync.

Let’s look at the following illustration:

Illustration high speed sync flash

The shutter speed of this photo is 1/1600s. The red rectangle shall illustrate the time which passed during this photo. As I was using a HSS (high speed sync) flash, the flash fired multiple times at a high frequency during this 1/1600s. The blue rectangles shall illustrate this.
As you can see, the flash was available during the whole exposure time. So we’re back at the topic from lesson 1, freezing the motion with the shutter speed. We can also say, the power setting of the flash doesn’t have any impact on its duration. We froze exactly 1/1600s of the motion of the milk.

Camera Settings
As in lesson 1, the most important setting with this technique is the shutter speed. It should be as short as possible, we compensate the missing light by using a flash. Maybe its possible to turn on HSS on cam and/or on flash. ISO isn’t very relevant in this technique. I often use a aperture of about f/10 to get a bigger depth of field. For this kind of images I use the manual mode of my cam.

Limitations
Depending on cam and flash it may be possible that either of it can limit the shutter speed, f.ex. on 1/4000s or something similar. Even if we use a flash it is possible that we haven’t enough light. Its also possible that the shutter speed is not fast enough to freeze the motion. Another disadvantage is that cheap flashes may not support HSS. Flashes without HSS can’t be used for this method. Another disadvantage is that most cams have a little trigger delay, this means some millisecond will last between pressing the shutter and beginning to record the image. The technique described in the next tutorial will solve all those problems.

When to use

Highspeed 101 - Lesson 2 Example

I used this method at the beginning of my highspeed photography work. I was lucky, as my first flash supported HSS. The first part of my ‘Milky Music’ series was done with this technique and also the on the image above I used this technique.

Conclusion
The main advantage of this method is that you gain some flexibility due to the extra light from the flash, overall in studio environment. One disadvantage is surely that you need the more expensive HSS flashes. All in all I’d say this is a good method for highspeed photography.