Nokia picture phone packs 41MP

Nokia was once far-and-away the world’s primary camera manufacturer by volume: its innovative camera-phones set the trend for mobile imaging, but the company has fallen from the leadership status it enjoyed a decade ago.

Now Nokia may be poised to reclaim that premiere position with its “PureView imaging technologies,” and a smartphone with a 41-megapixel sensor.

Despite that number, it’s not about resolution: “The real quantum leap,” the company says, “is how the pixels are used to deliver breath-taking image quality at any resolution.”

The PureView 808 smartphone has a 1/1.2-inch sensor. Pixel oversampling takes the output of seven 1.4 micron sensor wells, commonly called pixels, and combines them into one in-picture pixel “for the sharpest images imaginable” with “superior low light performance,” the company claims — albeit at a default 5MP resolution, not 41.

Also, a 38-megapixel maximum image size offers the capability to “capture an image, then zoom, reframe, crop and resize afterwards to expose previously unseen levels of details. superior low-light performance,” Nokia says — and to make poster-sized prints.

The phone can also save in compact file sizes for sharing in email, MMS, and on social networks, and capture 1080p HD video.

Additionally, Nokia says its “Rich Recording” enables audio at CD-like levels of quality with better microphones than most mobiles, and Dolby technology “transforms stereo content into a personal surround sound experience” for playback.

Two downsides: The new phone debuts only in Europe, and it uses the company’s old Symbian operating system instead of the Windows Phone OS from Microsoft that Nokia has already announced it will standardize on for its primary smartphone platform.

Pricing was not announced.

Nokia also introduced the Lumia 610, its most affordable Lumia model running Windows, at €189.

 

PureView Details

“PureView imaging technology is the result of many years of research and development, and the tangible fruits of this work are amazing image quality, lossless zoom, and superior low light performance,” Nokia says. It “doesn’t represent a step change for camera smartphones performance, so much as a quantum leap forward. It turns conventional thinking on its head. It dispenses with the usual scaling/ interpolation model of digital zoom used in virtually all smartphones, as well as optical zoom used in most digital cameras, where a series of lens elements moves back and forth to vary the magnification and field of view. Instead, we’ve taken a completely new road. The result? Unprecedented camera control and versatility, combined with truly spectacular-quality images and video.”

The PureView sensor at 1/1.2-inches is approximately 2.5 larger than the sensor used in Nokia’s N8, previously its top imaging model. The sensor has an active area of 7728 by 5368 pixels. Depending on the selected aspect ratio, it will use those pixels for 16:9 images and videos, or 7152 by 5368 pixels for 4:3.

The default still image setting is 5MP at 16:9 — which enables a 3x zoom. “Conventional zoom tends to scale up images from a relatively low resolution, resulting in poor image quality,” Nokia says. “We were convinced there must be a better way, and we found it. We’ve taken the radical decision not to use any upscaling whatsoever. There isn’t even a setting for it. When you zoom with the Nokia 808 PureView, in effect you are just selecting the relevant area of the sensor.”

Pixel oversampling also yields greater detail, and “filters away visual noise from the image,” Nokia adds. “The speckled, grainy look you tend to get in low-lighting conditions is greatly reduced. And in good light, visual noise is virtually non-existent.” Oversampling also eliminates some problems with the standard Bayer pattern: Conventional 8MP sensors have in effect only 4M green, 2M red, and 2M blue pixels, Nokia says, which are interpolated to an 8MP RGB image. “With pixel oversampling, all pixels become true R, G, and B pixels.”

Additionally, PureView yields effective maximum aperture throughout the zoom range, so 5.4x more light reaches the sensor than in an equivalent camera — meaning faster shutter speeds are possible as well.

The Carl Zeiss optics have a fixed 8.02mm focal length, with five aspherical elements in one group, and a mechanical shutter.

The 808 PureView “has taken so long to develop” Nokia adds, due to its need for processing power. “We simply couldn’t get hold of enough.” The company developed a sensor with a companion processor that handles pixel scaling before sending the data to the main image processor.

All told, the simple structure “beats more complicated designs hands down,” Nokia concludes. “Image definition is pin sharp, way superior to conventional zoom designs. Conventional designs need many more lens elements to provide the zoom capability and correct aberrations, but these interfere with definition and/or light transmission. Our simple structure has enabled a significant improvement in manufacturing precision, and our lenses are produced with 10x greater precision than SLR lenses.”

Nokia’s white paper [pdf] on PureView is here.

 

About Paul Worthington

Paul Worthington is a journalist and consumer imaging consultant. He produces the annual Future Imaging Summit at PMA@CES, and writes for PMA Newsline and PMA Magazine, as well as other publications.