Explaining the innovation behind the Nokia Lumia 1020 – Tidbits from the WhitePaper


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As you know by now, the Nokia Lumia 1020 is completely out in the open, and it is all about the camera. The 41 Megapixel sensor is back, and the Lumia 1020 takes over its predecessor as one of the best smartphone cameras ever. While the output is stunning, there is a lot of behind the scenes work going on inside the camera in terms of hardware as well as software, and as a tradition since the Nokia 808 PureView, Nokia have released a Whitepaper that details all the technological innovation packed in this cameraphone. We know that might be a hard read for the most of you, so we have done the heavy lifting of text crunching and are providing you with the most interesting tidbits out of it, read on!

Sensor, Lens and OIS

  • The second generation 41 megapixel sensor uses the latest generation 1.1 micron back-side-illuminated (BSI) pixels, providing excellent noise performance as well as benchmark resolution. The sensor format is 1/1.5” and it is up to five times larger than typical smartphone sensors.

You heard that right. The sensor size comes at 1/1.5″ with a pixel size of 1.1 microns. In comparison the Nokia 808 PureView with a 1/1.2″ sensor size and 1.4 micron pixel size, it is indeed a bit lesser, but if you read the above text closer, the 1020 has a backside illuminated sensor which massively improves noise reduction and low light performance of the camera. Also note that the HTC Ultrapixel camera has a 2.0 micron pixel size. Technically, the oversampled 5MP photo will have a larger pixel size than any other sensor, but that’s just in theory.

  • To provide the best optical resolution we increased the number of lenses used from the five in the award-winning Nokia 808 PureView, to six. The first lens element is made of high precision glass, and five of the lenses are mould-ed high-performance plastic, taking lens manufacturing precision to the next level. The lenses are physically very big for a smartphone, and the optical assembly alone is unique.

Interesting to note that the six element lenses(which was a world’s first on the Lumia 925) actually has a glass element and five more plastic lens elements. Glass should massively improve the clarity and sharpness. It is quite intriguing to see that Nokia have engineered a ridiculously complex assembly into a small unit. Impressive!

  • But that is not all. We put the whole system inside a completely new kind of optical image stabilisation system, which uses an extremely high accuracy sensing system linked to very small motors which actively move the lens.

There you go. There is a new OIS system for the Nokia Lumia 1020 that is different from those on the 920/8/5. According to the presentation, the OIS unit uses mechanical ball bearing and magnetically powered motors for stabilization during photo as well as video. The new OIS system is said to massively improve the already impressive OIS unit on the Lumia 92x. It is explained even further here –

  • In the Lumia 1020 the optics are much bigger, and adding OIS technology to optics of that size required some really clever engineering: the whole lens system is resting on top of ball bearings and is actively moved with very small motors to counteract the unwanted camera movements detected by a gyroscope.

Oversampling and High Resolution Lossless Zoom

Taking cue from the Nokia 808 PureView, the Lumia 1020 has a 5MP Oversampling mode and that alone, unlike the various 2/3/5/8 MP modes that are present on the 808. Why 5MP, you ask?

  • 5MP is the sweet spot for image quality that is easy to share and printable up to A3 size. And because our 5MP images condense the information from the 41MP sensor, they have amazingly high image quality.

We concur, having seen the effects on the 808. Expanding on the oversampling technology, it works on the principle of a super pixel. The super pixel on the Lumia 1020 is a 1.1 micron pixel combined with seven other pixels surrounding it, making it one big super pixel. The effect of that is a highly detailed pic devoid of noise. The noise is completely filtered out with the amount of data from each pixel and a better reproduction of the colour is achieved too. Good thing about the Lumia 1020 is.. –

  • The 41MP sensor can capture 34MP and 38MP image files at 16:9 and 4:3 aspect ratios respectively. In addition to the 38MP and 34MP full-resolution images, the Lumia 1020 camera captures 5MP oversampled images too.

Yes, the camera takes 16:9 and 4:3 pictures at 34 and 38 MP just like the 808 and also takes a 5 MP photo at the same time, which is the oversampled one. Pretty amazing, right! The use of the 5MP mode is further enhanced by the 3X high resolution lossless zoom.

  • In addition to oversampling, the large sensor also allows for high resolution zoom. As you zoom there is no drop in the default 5MP resolution; in other words the high resolution zoom is lossless. The level of pixel oversampling is highest when you’re not using the zoom. It gradually decreases until you hit maximum zoom where the pixels start behaving in a more conventional way.

In simple words, the oversampling is inversely proportional to the amount of zoom you apply. Similar to the 808. While explaining the advantages of high resolution zoom over traditional optical or digital zoom

  • With Nokia Lumia 1020, the aperture stays at a constant f2.2 throughout the zoom range which is, in SLR terms, 25/27-69/74mm (16:9/4:3) for stills and25-100mm for Full HD video.

So, the aperture is f2.2 which is obviously constant and not variable unlike the N86, and interesting the 3x high resolution zoom enabled comparable 35mm equivalent focal lengths of 25-69mm for 16:9 and 27-74mm for 4:3, and an even better 4x multiplier zoom with 25-100mm eq. focal length for full HD video. This will be 6x at 720p resolution.

  • Also as the aperture stays the same throughout the zoom range in the Lumia 1020, the macro distance of ~15cm also stays the same. With Nokia Lumia 1020 we are actually using the centre part of the lens where distortions, diffractions and lens shading are smallest, giving extremely high levels of resolved details and distortion-free images and videos throughout the zoom range.

From this, we can infer that the macro distance at zero high resolution zoom is 15cm while at 3x, it will be 5cm, which is not too bad.

Backside illumination, Xenon Flash and Long exposure

Touching upon the Backside illumination technology again –

  • With traditional pixels all these wires are located on top of the pixels and light must bypass the wires to reach the photosensitive area of the pixel. We used a modern-generation BSI sensor where all these wires are located underneath the pixel. With this design a significantly larger amount of light can actually reach the photosensitive area of the pixel. This again means that we can amplify the signal created by much lower levels of light, significantly reducing the amount of visible noise.

Nicely explained there, the BSI technology has been here for a while, but what’s impressive is that they have managed to do that on a huge 1/1.5″ sensor. For a comparison, the Galaxy S4 Zoom is much smaller at 1/2.3″ while smartphones like the Lumia 920 and the Galaxy S4 have a 1/3″ sensor.

  • With the Lumia 1020 we use a no-compromise xenon flash with very high light output and extremely short flash pulse duration. High flash output provides excellent illumination to targets three metres away, and the short pulse of the xenon flash ensures that the final captured image is extremely sharp while preserving the ambient lighting of the background.

Armed with a powerful Xenon flash, we are back to the days of the N82. The Xenon flash is said to be of the flat capacitor type which enabled Nokia to install them in a slimmer fixture, which was not possible earlier. They also say that the flash is very powerful. Impressive thing is, you can also manually set the flash to on and still preserve ambiance by varying the shutter speed and other exposure related controls. Talking of exposure –

  • With its OIS system, the Nokia Lumia 1020 camera can actually tolerate up to of 3-5 times longer exposure times compared to traditional mobile cameras – a significant benefit in low light situations. Using the Lumia 1020 together with a tripod, users can manually set the exposure time up to 4s, which allows you to take amazing images in nearly complete darkness.

That’s right, 4 second exposures can be achieved on the Lumia 1020. Previously this was possible on apps like Camera Pro on Windows Phone but the sensors in the other phones weren’t that good to handle the longer exposures, but we think the 1020 will do just fine. The 808 could do 2.7s when forced. Coupled with the Xenon flash, the 1020 presents some intriguing long exposure options for creative photographers. I personally can’t wait for light tracing.

Manual Controls in Nokia Pro Camera

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Nokia’s Pro camera app is a marvelous interface for the immensely powerful camera. With intuitive dials for controlling various features, the app is rightly aimed at professional cameraphone users who want complete control over the camera. You have manual controls for a lot of the exposure parameters in Nokia’s own Pro Camera app. Shutter speed varies from 4s to 1/16000s, and there is a mechanical shutter of course. The ISO can go upto 3200, right from 100, and you can even change the focus manually. Only component of exposure not available is the aperture, which you can compensate with the EV exposure compensation. And regarding video –

  • Nokia Pro Camera records video in two different resolutions, 1920×1080 (Full HD) or 1280×720, and also supports three different frame rates, 24, 25 and 30 frames per second (fps), depending on which region you are intending to play back the video in.
  • The indicator bar shows three manual controls. You can turn the video light on and off. You can set the white balance. You can lock the focus manually.

Yes! Like the 808, you can manually lock the focus on video and even set some sort of control over white balance. Pretty neat, but a manual control over ISO and even shutter speed would have been nice for greater control. The frame rates are locked at 24, 25 or 30, which is welcome.

Rich Recording

The Lumia 1020 becomes the first Nokia Windows Phone device to use rich recording in stereo. The Nokia 808 had it, and the Lumia 1020 gets it. Not only that, additional settings have been introduced for pro users –

  • Audio bass filter provides controls on the low frequency audio characteristics with three options: The “Default” option is the best all-round setting and provides sonically balanced recordings in most conditions. It applies a shelf filter to 0…200Hz frequency band and works especially well in loud concert recordings, where the bass level can be too excessive for balanced playback. The “Strong” option can become handy in the presence of wind-noise or in-car noise. It applies a 200Hz high- pass filter cutting effectively all low frequency content 17 from the recording. The “Off” option is convenient for more advanced users who may want as flat a frequency response as possible for post editing. It extends the low frequency range down to around 20Hz without attenuation.

Those are some pretty extensive options, and it is great that Nokia has listened to feedback from the pros, for the pros.

And that’s about it. Phew, going through the document really proved challenging, and if you could read through till here, we appreciate the effort. But then, if you really want more, you can always get the rest of the extra information from the Whitepaper itself in the source link below. We’ll be bringing you more coverage in videos and text, so do check back in some time! And for quick updates on videos, do subscribe to our YouTube channel!

Source Nokia


Author: Bharadwaj Chandramouli

Bharadwaj is a content creator who has been obsessed with technology since the early days of smartphones. He loves talking about tech, is a fan of good design and photography. You can follow him on Twitter @gadgetbuff_ to know what he's upto!