iPhone 4S Camera Review: Performance

PERFORMANCE
Those who are used to handling a point-and-shoot camera will find the ergonomics of the iPhone camera slightly frustrating, but aside from that camera performance is quick.

Shooting Performance
The camera app loads in around three seconds, and as soon as it's active the camera begins to continually auto focus. A blinking white box appears as the camera locks in on its target. Face detection will present a green box when a face is detected and used as a focus target. I found face detection reliable, and it wasn't overly aggressive in hunting for faces where they aren't.

Shutter lag is as good as any current point-and-shoot - a negligible 0.01 seconds. AF acquisition is in the middle range for point-and-shoots that we test. It's hard to nail down an exact figure since the 4S is always searching for focus, but it clocks in consistently around 0.30 seconds. There is no continuous shooting mode on the iPhone 4S, but shot-to-shot times are very quick. As soon as an image is recorded, the iPhone is basically ready to shoot the next one when you are.

The iPhone's tiny LED flash is quite powerful for its size. It will do a fine job of illuminating a subject when no other light source is available, but in low light it often overpowered close subjects and washed out skin tones. Unless there's no other option, it's best to leave the flash off and use in or out of camera editing options.

Battery life is another drawback to the phone/camera combo. If you spend all day on email, YouTube, Facebook, Twitter, you'll find at the end of the day there's no battery power left for that spontaneous Polaroid moment. When the phone dies, your camera dies, and the iPhone 4S isn't exactly a battery-efficient machine. The good news is - at least the iPhone 4S that I've been testing - has stronger battery life than smartphones of the past year or two. Still, there's no way to carry an extra battery the way you can with a dedicated camera. Once it's done, it's done.

Lens Performance
Sharpness is good, though some of it appears to be created by the image processor. In dim light, sharpness is somewhat compromised as noise suppression kicks in.

Distortion is well controlled and there's very little evidence of any in the photo below. Moire popped up every once in a while when photographing a screen or wallpaper with a fine grid pattern.

Digital zoom isn't particularly helpful. It's nice to have in a pinch when there's no way to get closer to your subject, but even in fair lighting conditions digital zoom will make the noise in your photos much more noticeable. It's also a difficult proposition keeping the camera steady with the camera digitally zoomed in on a subject.

Full digital zoom

There's no way to get around it - the iPhone lens is perfectly functionally until you want to zoom in on a subject. A little digital zoom won't do too much harm, but for any real magnification this lens just doesn't cut it. This is still point-and-shoot, ultrazoom and DSLR territory.

Video Quality
Video quality looks closer to point-and-shoot quality than it does to phone-quality. The sample video below was originally published in our sister site Brighthand's iPhone 4S Review, and we've repurposed here to show the fluidity and sharpness of the clip.

Naturally there's quite a bit more noise in low light video, but not an overwhelming amount. Again, the ergonomics of the iPhone work against the user when shooting video. Keeping the phone stabilized in the hand is a tricky proposition. Many low-end point-and-shoots have better video ergonomics and optical image stabilization to keep video fairly steady - the iPhone 4S shoots very nice video, but it's hard to imagine it being used primarily as a video device. Its natural advantage is the ease with which it can send videos to sharing sites - just a few screen taps and you can upload your clips straight to YouTube, and there's no point-and-shoot (yet) capable of that.

Image Quality
To my eye, sharpness and contrast are a bit hard. The details on the purple house below are good examples. That same photo viewed at 100% will show some loss of detail and noise in the corners, especially in the tree branches. Some highlights are lost in this high contrast scene and some color noise is visible in the blues of the sky.

Then again, this is a photo taken with a device that is engineered to make calls and receive e-mail. That's the thing about the iPhone 4S camera - it's so easy to forget that it's not one. No doubt a high quality point-and-shoot would handle this scene better, but for a quick-and-easy phone picture it's pretty impressive.

The iPhone 4S seemed to handle color reproduction very well in good to moderately poor lighting conditions. The purple façade of the house above is accurately reproduced. In very low light, colors are flat and details are smudged due to noise suppression. Holding the phone steady for a clear image becomes a tricky proposition in low light, and photos that appear to be in focus on the phone screen may actually be blurred due to shake. Case in point, curry.

Most other low light images suffered the same fate. If they weren't actually blurry, then details were too smudged for printing of any significant size. They're acceptable for tweets and Facebook updates of course, but even viewed at 50 and 25% on a computer screen noise is evident and loss of color depth is obvious.

There's just one shot from our studio in this review, since there's really only one ISO and white balance setting on the iPhone 4S - automatic. The processor handles our 5500k studio fluorescents very well.

There's a faint suggestion of grain in the shadow areas but outside of that it's a very good reproduction of our studio still life. Again, it appears somewhat oversharp to me, but most iPhone photos will only ever be viewed on small screens and a little sharpening helps details pop.

We used the Gary Fong tripod adaptor for iPhone for our studio shots with great success.

Additional Sample Images