Nokia 808 PureView

The Nokia 808 PureView is a Symbian-powered smartphone first unveiled on 27 February 2012 at the Mobile World Congress. It is the first smartphone to feature Nokia's PureView Pro technology, a pixel oversampling technique that reduces an image taken at full resolution into a lower resolution picture, thus achieving higher definition and light sensitivity, and enables lossless digital zoom.[5] It was one of the most advanced camera phones at the time of its release in May 2012.[6][7]

Not to be confused with Nokia 9 PureView.
Nokia 808 PureView
ManufacturerNokia
PredecessorNokia N8
SuccessorNokia Lumia 1020
Dimensions123.9 mm (4.88 in) H
60.2 mm (2.37 in) W
13.9 mm (0.55 in) D
17.95 mm (0.707 in) Bulge
Mass169 g (6.0 oz)
Operating systemNokia Belle Feature Pack 1, upgradeable to Nokia Belle Feature Pack 2
CPU1.3 GHz Texas Instruments 4377622 ARM11 processor[1][2]
GPUBroadcom BCM2763 with OpenVG 1.1 and OpenGL ES 2.0 support[2][3]
Memory512 MB RAM
Storage16 GB on-board memory
Removable storagemicroSD up to 128 GB supported[4]
BatteryLi-Ion; BV-4D 1400 mAh 3.8 V
Display4 in (10 cm) AMOLED 2.5D curved nHD display (640x360 pixels)
Gorilla glass with easy-clean coating
Rear camera41 MP 1/1.2 in sensor
Carl Zeiss optics
F-number: f/2.4
ND filter
Xenon flash
LED light
1080p 30 fps video with continuous autofocus
Front camera0.3 MP; 480p 30 fps
ConnectivityBluetooth 3.0
Wi-Fi 802.11b/g/n
DLNA
Micro HDMI
Micro USB
USB On-The-Go
Secure NFC
3.5 mm audio connector with TV-out
FM transmitter
GPS with A-GPS
Band I (W-CDMA 2100)
Band II (W-CDMA 1900)
Band IV (W-CDMA 1700)
Band V (W-CDMA 850)
Band VIII (W-CDMA 900)
GSM 850/900/1800/1900[3]
Development statusDiscontinued
PureView Pro Sensor with image circle and the 16:9 and 4:3 image areas

The Nokia 808 features a 41 MP 1/1.2 in (10.67 × 8 mm) sensor and a high-resolution f/2.4 Zeiss all-aspherical 1-group lens. The 808's sensor was the largest (over 4 times larger than typical compact cameras) sensor ever to be used in a cameraphone at the time of its launch, a record previously held by Nokia's N8[8] and, as of September 2014, by the Panasonic Lumix CM1.[9] The resolution of the sensor remained the highest to be used in a cameraphone until January 2019, when the Honor View 20 was released with a 48 MP sensor.[10]

The 808 won the award for "Best New Mobile Handset, Device or Tablet" at Mobile World Congress 2012,[11] and the award for Best Imaging Innovation for 2012 from the Technical Image Press Association.[12][13] It was also given a Gold Award by Digital Photography Review.[14]

On 24 January 2013, Nokia officially confirmed the 808 Pureview to be the last Symbian smartphone.[15] In July 2013, Nokia released the Lumia 1020, a successor running the Windows Phone operating system common to Nokia's newer products.[16][17][18]

PureView Pro camera

PureView Pro is an imaging technology used in the Nokia 808 PureView device. It is the combination of a large 1/1.2 in,[19] very high-resolution 41 MP image sensor with high-performance Carl Zeiss optics. The large sensor enables pixel oversampling, which means the combination of many sensor pixels into one image pixel. PureView imaging technology delivers high image quality, lossless zoom and improved low light performance (see below). It dispenses with the usual scaling/interpolation model of digital zoom commonly used in other 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. In both video and stills, this technique provides greater zoom levels as the output picture size reduces.

Image sensor

The Nokia 808 has a 41.3 megapixel 1/1.2 in CMOS FSI image sensor with 7728x5368 pixels. Pixel size is 1.4 µm; sensor size is 10.67 × 8.00 mm.

Depending on the aspect ratio chosen by the user, the sensor will use either 7728x4354 pixels (33.6 MP) for 16:9 images, or 7152x5368 pixels (38.4 MP) for 4:3 images when using the default camera software, although third-party apps exist that can capture the full resolution of the sensor. The output from the sensor is processed using the on-chip image processor, resulting in a lower-resolution image with pixel oversampling, lossless digital zoom, or a combination of both. The image processor highly reduces external processing needs and data rates as well as image noise (see noise shaping). At default settings, maximum zoom is 3x for stills (5 MP in a 16:9 aspect ratio) and 4x for video (1080p).

Zoom

Zoom is digital but retains a high resolution due to the 41 MP sensor. The limit of the zoom is reached when the selected output resolution becomes the same as the input resolution. That means once the area of the sensor reaches 3072x1728, the zoom limit is reached. So the zoom always provides the true image resolution the user wants. The level of pixel oversampling is highest when zoom is not used. It gradually decreases until the maximum zoom is hit, where there is no oversampling. At this stage, PureView Pro optics and pixels start behaving in a more conventional way. But because only the centre of the optics is used, the best optical performance is achieved – including low distortion, no vignetting and highest levels of resolved detail. This also means that at full digital zoom, the noise reduction achieved by oversampling (pixel binning) is lost as no oversampling happens at full zoom.

Autofocus
The 808 PureView compared to its successor, Lumia 1020

PureView Pro features continuous autofocus in all shooting modes, close-up (Macro) focus, face detection, touch focus with easy manually selected focus point and hyperfocal distance focus for defined depth of field, for extreme focus speed or when reliably achieving focus is not possible.

Video

The on-chip oversampling image processor of the 808 enables oversampling of all 38 megapixels even at the high video data rates of 1080p with 30 fps. Maximum possible zoom is 4x for 1080p, 6x for 720p HD and 12x for nHD (640x360) video. In addition, encoding is up to 25 Mbps in 1080p H.264/MPEG-4 HD video format. The PureView Pro sensor integrates a special video processor that handles pixel scaling at up to 1 billion pixels per second[20] before sending the required number to the main image processor.

Lens
The camera of the 808 has a very large and noticeable hump

The 808 has Carl Zeiss 5-element lens with f/2.4 aperture and 8.02 mm focal length (35 mm equivalent focal length is 26 mm in 16:9 and 28 mm in 4:3 aspect ratio). Focus range is from 15 cm to infinity (throughout the zoom range).

The optics are based on a shiftable fixed-focus lens; similar to the prime lenses in most Zeiss Planar or Tessar optics, focus is achieved by varying the distance to the image sensor (unit focusing lens). This construction has the advantage that no movable focus group is needed. Considerable movable (focus-range) lens groups need a minimum of one additional adaptive lens element in both the moved group and the stationary group, increasing the number of elements by at least two. This increases unwanted reflections as well as overall tolerances and therefore decreases sharpness.

The lens consists of only 1 group with molded elements, which gives a highly stable, precise mechanical alignment. The lenses are partly made of plastic, which provides sufficient stability at this size and as a 1-group lens and has the significant advantage of making it possible to use extreme aspheric shaped lens elements.[21]

5 all-aspherical lens elements are used, making it possible to increase border-sharpness and lower distortion and astigmatism. The high–refractive index, low-dispersion glass additionally helps reduce chromatic aberrations. A neutral density filter with approximately ND8 (3 f-stops) is employed for shooting in high light levels where normally a smaller aperture would be set. Although the lens is named a Tessar, it has almost nothing in common with the 4 element in 3 group, non-aspherical original Tessar.

Due to the comparatively large 1/1.2 in sensor and the comparatively fast lens with f/2.4 aperture, the camera has a quite shallow depth of field, equivalent to approximately f/7.8 at 26 mm[22] on 35 mm full-frame.

Shutter

The 808 has a mechanical shutter with short shutter lag[20] and ND8 (3 f-stops) neutral density filter.

Audio

The 808 PureView employs Dolby Headphone software to transform stereo content to surround via a 3.5 mm A/V jack. It also includes Dolby Digital Plus software to provide 5.1 surround sound via HDMI or DLNA. The dual software elements from Dolby are embedded into the Nokia Belle feature pack 1 OS.[23]

The 808 PureView is the first device to include the Nokia Rich Recording technology and has a frequency range between 25 Hz to around 19 kHz. The 808 PureView can capture sounds at the loudness level of up to 145 decibels without distortion. The two microphones, located at the top and the bottom enable ambient stereo recording. The audio encoding is done in AAC high profile, 256 kbit/s, 48000 Hz.[24]

References
  1. "Inside the Nokia 808 PureView Smartphone – 41 MP Camera!". Chipworks. 19 July 2012. Archived from the original on 2013-10-15. Retrieved 2014-02-19.
  2. "Nokia 808 PureView". The Verge. Vox Media. Retrieved 2015-09-14.
  3. "Device Details - Nokia 808 PureView". Nokia Developer. Nokia. Archived from the original on 2013-10-29. Retrieved 2013-12-09.
  4. Litchfield, Steve (2 May 2014). "128GB a go in the Nokia 808 PureView?". All About Symbian. Retrieved 2016-01-11.
  5. "41MP Nokia 808 smartphone hints at pixel-binning future for small sensor cameras". Digital Photography Review. 27 February 2012. Retrieved 2012-02-28.
  6. Vasile, Cosmin (1 March 2012). "MWC 2012: Nokia 808 PureView Wins "Best New Mobile Handset, Device or Tablet" Award". Softpedia News. Softpedia. Retrieved 2015-10-07. Nokia 808 PureView has just become the most advanced camera phone that will soon be available on the market.
  7. "Just Posted: Nokia 808 PureView Review". Digital Photography Review. 30 July 2012. Retrieved 2015-10-07. On paper, the 808 offers the most advanced camera features of any smartphone...
  8. Turner, Debbie (28 February 2012). "Nokia 808 PureView 41MP phone could kill compact camera". Phones Review. Retrieved 2012-02-28.
  9. Rehm, Lars (15 September 2014). "Panasonic announces Lumix DMC-CM1 smartphone with 1-inch sensor". Digital Photography Review. Retrieved 2015-12-05.
  10. Frumusanu, Andrei (28 January 2019). "Honor Launches The View20: A 48MP Camera Review". AnandTech. Purch. Retrieved 2019-02-21.
  11. Delaney, Ian (1 March 2012). "Best of show: Nokia wins prestigious MWC award". Lumia Conversations. Microsoft. Retrieved 2015-09-14.
  12. "Best Imaging Innovation: Nokia PureView technology". Technical Image Press Association. Archived from the original on 2012-05-11.
  13. "Nokia 808 PureView and Samsung Galaxy Nexus get imaging awards". GSMArena. 25 April 2012. Retrieved 2015-09-14.
  14. Britton, Barney (30 July 2012). "Review: Nokia 808 PureView". Digital Photography Review. Retrieved 2013-12-09.
  15. Lunden, Ingrid (24 January 2013). "Nokia Confirms The PureView Was Officially The Last Symbian Phone". TechCrunch. AOL. Retrieved 2015-09-14.
  16. "Nokia Lumia 1020 hands-on". GSMArena. 11 July 2013. Retrieved 2016-05-12.
  17. Litchfield, Steve (11 July 2013). "The Nokia 808's successor is unveiled.... on Windows Phone 8". All About Symbian. Retrieved 2016-05-12.
  18. Carter, Kevin (11 October 2013). "Nokia Lumia 1020 overview: Has the best got better?". DxOMark Mobile. DxO Labs. Retrieved 2016-05-12.
  19. Litchfield, Steve (27 February 2012). "Nokia 808 PureView announced, dramatically extends world camera phone leadership". All About Symbian. Retrieved 2015-09-14.
  20. Degli-Esposti, Emanuelle (6 March 2012). "Nokia 808 PureView: your questions answered". Nokia Connects. Nokia. Archived from the original on 2012-04-21. Retrieved 2015-09-14.
  21. Bartlett, Karen (5 March 2012). "Nokia 808 PureView: Carl Zeiss science of making the perfect lens". Lumia Conversations. Microsoft. Archived from the original on 15 May 2015. Retrieved 2015-09-14.
  22. Horaczek, Stan (27 February 2012). "Nokia 808 Pure View Smartphone Has a 41-Megapixel Camera Sensor". Popular Photography. Bonnier. Retrieved 2013-12-09.
  23. Ebert, Stephen (22 March 2012). "Dolby Headphone for Nokia 808 PureView: what is it?". Lumia Conversations UK. Microsoft. Retrieved 2015-09-14.
  24. Fraser, Adam (23 March 2012). "Nokia 808 PureView and Nokia Rich Recording brings true stereo sound". Lumia Conversations. Microsoft. Archived from the original on 29 July 2015. Retrieved 2015-09-14.
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