When to Use Anti-Shake

Sometimes, You Have to Turn it Off

I can already hear the cries of protest.

Why in the world would you spend money on an advanced digital SLR camera that includes built-in anti-shake, and then go and turn it off?

There's a perfectly good reason for doing so, and here's the key: it all depends on how fast your SUBJECT is moving.

The Benefit of Anti-Shake

I think anti-shake is a fantastic tool for the average snapshot photographer, and that's why it's no surprise that many more SLR and compact digital cameras are including this helpful technology.

The big deal here is that anti-shake reduces camera vibration when you hold your SLR in your hands, which in turn leads to clearer photos. That's the simple definition.

The more complex one is that anti-shake helps you take clear photos when your camera selects a slow shutter speed to get a correct exposure. The slower the shutter speed your camera uses, the higher your chance of getting a blurry photo due to camera shake.

Let's put this into table form to illustrate your chances of getting a blurry photo at different shutter speeds:

Shutter Speed	Without Anti-shake	With Anti-shake
1/500th of a second	Zero	Zero
1/250th of a second	Low	Zero
1/125th of a second	Moderate	Low
1/60th of a second	High	Moderate
1/10th of a second	Very High	High

See what's happening here? Anti-shake just reduces the probability of blurry photos, since you can use very slow shutter speeds and still get clear images (without anti-shake those same slow shutter speeds result in blur).

No-Flash Photography

Key point: anti-shake only applies when you're not using the flash.

The minute you activate your camera's flash, anti-shake's ability to counteract slow shutter speed no longer applies. The reason is that the camera wants to activate the flash when it senses that there isn't enough light. As soon as the flash is active, the camera will set a shutter speed (typically around 1/60th of a second) so that you won't get a blurry photo.

Your flash must be turned off in order for anti-shake to work its magic at shutter speeds slower than 1/60th of a second.

This is why anti-shake is an incredibly useful feature for anyone who takes photos indoors without a flash: specifically, the interior of houses, museums and aquariums. If you want to take some photos of your relatives standing in front of an ancient artifact, anti-shake will ensure that your photo turns out crisp and clear.

But if those same relatives are romping all over the museum, your trusty anti-shake isn't going to do a bit of good.

Static Subjects

Even though the anti-shake is working to reduce the camera's vibration, the only thing that will freeze the motion of a fast-moving subject is a fast shutter speed. Since the use of anti-shake doesn't necessarily increase your shutter speed, it won't help you get clear shots of fast-moving subjects.

Let's use some concrete examples that will help clarify what's going on here.

Scenario One

You're in the living room and find your child asleep on the floor - this is just too good to pass up
You take out your camera and prepare to take a photo - you disable the flash and notice that the camera wants to use a shutter speed of 1/30th of a second
RESULT: with anti-shake activated, this shot will turn out quite clear

Scenario Two

You're in the living room and find your child jumping from one couch to the other
You still don't want to use the flash and the camera selects a shutter speed of 1/30th of a second
RESULT: while the room will be quite clear (it's not moving around) your child will just be a blur. 1/30th of a second is NOT fast enough to freeze the motion of a jumping child (or any other moving subject for that matter).

In scenario number two anti-shake isn't going to help you get the clear photo that you're looking for - might as well turn it off. Instead, use two other techniques that WILL increase your shutter speed:

Open your lens up to its widest maximum aperture AND
Increase the ISO setting on your camera

Doing these two things (and not relying on your anti-shake system) will ensure that you get a clear photo in dim lighting (without the flash), even though your subject is moving all over the place.