Nokia 808 PureView Smartphone: Really a 41mp Camera in There?

Pictured above: +Trey Ratcliff’s Google+ stream showing him and the Nokia 808 PureView shipping later this month.

At MWC 2012, Nokia announced the 808 PureView, a Symbian smartphone it claimed would include a 41mp camera when it ships later this month.

And no, that isn’t a typo.

A 41mp camera on a smartphone? Sounds like crazy talk. But that’s what Nokia announced. So I dug in. The tech it’s using is pixel binning — combined with a sampling technology Nokia developed that allows for extra deep zoomtech. It is worth noting that Samsung has a patent on pixel binning and that a compact camera from Sony will be coming out soon with similar tech.

The announcement shocked attendees because even the best smartphones today from Apple and others offer 8mp cameras — just a few include 10mp cams. Pro cameras — such as the Nikon D800 — capture 36mp images. What gives here?

We want to know if that’s a real 41mp or a marketing spec based on some process-enhancing software. That’s so far unclear. At any rate, even the 38mp quality Nokia prototypes are capturing are quite the leap from Nokia’s other smartphones and anything else in the mobile smartphone market. As you can see, our contributor +Trey Ratcliff, in the Google+ post you see, checked one out yesterday. Notice the comments that follow it. We’re not the only ones curious about this outrageously high-end smartphone spec.

Ratcliff couldn’t tell us more beyond what you see in his post, pic and comments. That’s due, we’re guessing, to his non-disclosure agreement with the company. “I can keep a secret,” he told my colleague, Gina Smith.

But drawing from his comments on the stream and a whitepaper Nokia posted explaining the technology, this smartphone looks to be capturing pics not at 41mp, but at 38 mp (at a 4:3 aspect ratio) and 36mp (at a 16:9) aspect ratio. +Trey Ratcliff wrote that in his comments, too, as you see. But why the disconnect? I’ll be exploring the tech for you as I dig into the whitepaper.

Here was the reaction to Trey’s post.

Carl Zeiss Optics
Focal length: 8.02mm
35mm equivalent focal length: 26mm, 16:9 | 28mm, 4:3
F-number: f/2.4
Focus range: 15cm – Infinity (throughout the zoom range)
Construction:
• 5 elements, 1 group. All lens surfaces are aspherical
• One high-index, low-dispersion glass mould lens
• Mechanical shutter with neutral density filter
Optical format: 1/1.2”
Total number of pixels: 7728 x 5368
Pixel Size: 1.4um

DPreview.com ran a great article recently doing a deep dive into the technology.

The first thing to realize is that this isn’t a standard 1/3.2″ mobile phone sensor, it’s an unusual and remarkably large 1/1.2″ type (five times larger). In fact, it’s almost three times the size of the sensors in most compact cameras. As a result, its photo sites are the same size as those in most 8.2MP camera phone but the 808 doesn’t try to create an image of the same quality, 5 times bigger. Instead it over samples the image and then pixel-bins (using proprietary algorithms Nokia says optimize detail retention) down to a smaller size (though there is a special ‘creative’ shooting mode if you want the full resolution – 38MP at 4:3 aspect ratio, 36MP at 16:9).

This pixel-binning means that noise (which occurs randomly) is averaged-out across multiple pixels (around 7-to-1 in the 5MP mode). The high native pixel count also means that it’s possible to effectively ‘zoom’ by cropping into the center of the image and reducing the number of pixels you average together. Consequently the 808 can offer a roughly 2.8x ‘zoom,’ while maintaining 5MP output, despite having a fixed lens. The image quality will drop (since the noise is no longer being averaged out), but it does mean you get a roughly 28-78mm equivalent zoom, without the need to have moving lens elements, making the process fast and silent. It also means the lens’ 15cm minimum focusing distance is maintained …

So those are the specs. What does that mean when you go to shoot with the Nokia 808 Pureview?

Well to start, the Nokia 808 Pureview has Carl Zeiss Optics.

It has a huge sensor. A sensor is like your 35 mm film that captures your images. The bigger, the better. It’s able to capture more pixels and thus better resolution overall. In fact it has enough room to capture 7728 x 5368 pixels and that totals a 41mp! Most smartphones have at most a sensor 1/3.2″ while the 808 has a 1/1.2″ type which is five times larger!  That’s almost three times the size of the sensors in most compact cameras.

Samsung has a patent for the pixel binning technology. A forum on Ars Technica showed a lively debate on how exactly this is implemented, whether Nokia really has anything proprietary here and how the tech would be implemented with other photo features on this smartphone and others.

Combine the Carl Zeiss optics with a large sensor utilizing Nokia’s pixel over-sampling technology — Nokia’s so-called proprietary algorithms optimizing detail retention and here’s what you get, Nokia says. A camera that captures seven pixels of information and then condenses those into one single pixel, turning it into a sharp 5mp photo! The standout feature, say sources who’ve looked closely at the camera, is the ability to do serious zooming. Zoom into any portion of it up to 3x without losing any of the details in your shot.

According to Nokia, the PureView also has a special special ‘creative’ shooting mode if you want the full resolution — it at most offers a 38mp at 4:3 aspect ratio, (the aspect ratio is describing the proportional relationship between its width and its height) and thus only 36mp when its at 16:9. Why not 41mp as advertised, though? That is the big question here. We are looking into the Samsung patents to gain a better understanding.

In addition to all this, Nokia claims the cam on its phone shoots 1080p video. It also has Nokia’s so-called Rich Recording technology for ultra high quality stereo audio recording. While most high end smartphones can only record without distortion to around 110db, the Nokia 808 go up to 140-145 db, Nokia’s whitepaper claims. That’s about four times louder than conventional mics can record. It also, Nokia claims, is capable of recording low frequencies also without any distortion. The combination of all of
these elements means the Nokia 808 records audio with almost CD like quality, says Nokia.

With Nokia announcing this and sources telling us that Sony, too, is implementing similar technology, there are still more questions than answers. The proof will be in the review.

Here’s a video from the The new Nokia 808 PureView launched at Mobile World Congress 2012.