Nokia 9 PureView – Tech Behind The Camera Explained
Nokia 9 PureView is an unique device. It’s the first phone on the market featuring five cameras on the back, that are a result of collaboration between multiple companies, including HMD Global, Light, FIH Mobile, ZEISS, Google, and Qualcomm. The 9 PureView brings a new way of taking photos on the smartphone market, just like its namesake the Nokia 808 PureView did.
On February 24th, HMD Global, the maker of Nokia phones, officially announced the Nokia 9 PureView. Even though the Nokia 9 PureView can be a capable flagship that will satisfy almost all flagship users, the main feature of this device is the camera. Primarily because it’s a real innovation, by the definition of innovation, on the market and we will take a deeper dive into the camera tech in this article.
The back camera system of the 9 has five camera sensors with 12MP resolution and f/1.8 aperture. Three of the cameras, the top, right and left one are monochrome – creating a triangle, while the central and lower camera have an RGB sensor, with 1.25um pixel size. Details about the sensor, number of lens elements and similar information aren’t something HMD was keen to share with us, but Suomimobiili.fi found out that they are supplied by Sony. The ZEISS people told us that they can’t discuss closely about the number of lens elements but the cameras definitely doesn’t have less than 5 (they probably have 6). If you’re asking why the sensors are placed in that way, the answer we got it’s that it is optimal for the camera configuration. HMD had different prototypes and camera placements, but as it is always with R&D, you take the best solution you have for the final product.
The basic principle on which Nokia 9 works is that the device utilizes all five cameras at the same time. All the other phones on the market can work only with two camera feeds at the same time. For example, Nokia 7 plus has a main 12MP that works all the time and sends the image feed to the Image Signal Processor of Snapdragon 660. Once you press the 2 times zoom option, the telephoto camera kicks in and then the camera feed from the telephoto camera is sent to the ISP. On Nokia 8, where we have a main 13MP RGB camera and a 13MP monochrome camera, both image feeds are sent at the same time to the ISP, that fuses them together, using the data from the monochrome sensor for better contrast, depth sensing and to capture more light. Phones that have a telephoto lens or an ultra wide-angle lens activate these sensors once the user selects the option in the UI, while some use them also for depth information with the main camera for bokeh effect.
On the other hand, Nokia 9 has five cameras that simultaneously send data to the image processing system, which couldn’t be possible without Light and their dedicated camera hardware. Snapdragon 845’s ISP supports only two camera feeds at the same time, so Light’s hardware takes all the five feeds and makes them ready for further processing. Light has a patented solution for handling that amount of data, that is sent via a pipeline that basically prepares the data for the ISP. But not only ISP – HMD worked with Qualcomm to make the most of the Snapdragon chipset, so image processing takes place also on the DSP and GPU, as well. HMD claims that sharing the workload is more power efficient.
The exact amount of data the dedicated camera hardware handles is 60MP per shot or 240MP when each of the cameras takes multiple shots, depending on the conditions. The three monochrome sensors take photos at different exposure values for better dynamic range, and capturing at the same time the details in shadows and from highlights. The benefit of a monochrome sensor is the ability to take more light than an RGB sensor. To be precise, a monochrome sensors takes 2.9 times more light than an RGB sensor. The sensors might seem nothing special when they work independently, but together they open a new set of possibilities. Option of capturing native black and white images is there as well.
It’s interesting that the feed you see when you open the camera app comes from the central RGB camera. There is no real-time stitching, something like that would be impossible to do in real time, but the stitching kicks in once the photo is shot. That much data requires time to be processed, so when you take a shot, the device keeps processing the photo in the background. To allow users to take one photo after the other, there is a buffer that stores the images waiting to be processed without slowing the phone down. So there is no need to wait to take another shot, but you have to wait until the photo is processed to edit or share it over the device.
This way of taking multiple shots and creating a single picture of it requires clever algorithms, something that HMD’s team and ZEISS have been working on. Light might have a great way in stitching all the data together, but a huge job is on the companies they partner with, like HMD, to make sure everything is perfectly aligned and that that much of data is used and processed in the best way for the best shot. It’s interesting that all five camera sensors are flat with the surface, so making sure the pixels from every camera aligns perfectly is a priority.
The other thing is all the options the users can have with that much information. Changing the part of the photo in focus and adjusting the blur is something HMD has demoed on Nokia 9 a lot, and you can really make the bokeh effect practically with everything you have in the photo. A demo Oliver from ZEISS showed to us is from a photo he took in the stairway of the hotel he is staying, and how you can change the focus floor by floor. Other demo photos have different kinds of fruits and vegetables demoing this one use case a user can have while editing on the device.
The black circle in the camera system on the back is a ToF sensor, or time of flight sensor. ToF allows the camera to calculate the distance an object is located from the camera by measuring the time light reflects from an object back to the ToF, which allows better focusing, especially in low-light, when autofocus can struggle a lot. Thanks to this and the monochrome sensors, the phone is also able to create a depth map (something that users that don’t want it can turn off) with over 1,200 layers.
Users familiar with photo editing will benefit the most from the 9 PureView and they are exactly the targeted audience for this device. The 9 supports export of RAW files, so everyone who likes to finetune their photos can do that using the huge amount of data a photo from the 9 has. The camera guy from our crew that flew to MWC said that there is a huge amount of data for a phone, which will make folks that like to do that happy. There is also the option of editing RAW images on the device using Adobe Lightroom.
Users less keen to editing will appreciate the higher dynamic range and more natural looking colors from photos from the 9 PureView. Color reproduction of Nokia 9 PureView is really precise. After Oliver from ZEISS pointed out how natural the colors from the 9 are, he also said that you can get out from a photo even more than your eye can see at that moment. Two of the best examples of the Nokia 9’s natural color reproduction follows down below. One is a photo comparison that has been circulating for few days online with the Mate 20 Pro, and the other is a comparison we made between the Nokia 7 Plus and 9 PureView. Besides color, the details the photos from 9 have compared to others is also worth mentioning.
Ready for a quick comparison?
Top is the @nokia 9 PureView (pre-release software) and bottom is the @HuaweiMobile #Mate20ProThoughts? pic.twitter.com/J7wLuq74Uk
— David Cogen (@theunlockr) February 24, 2019
The end result of the Nokia 9 PureView’s image processing is a 12MP JPG file. The DNG file, if that options in enabled in settings, is also saved and also goes to Google Photos. The on-device editors give you an option to save your creations as a copy and retain the original image (something all editors do), so you can continue editing photos as much as you want. The final JPG image is around 4MB in size (the size of the photo depends on what you are shooting), but if you do editing it can jump to dozen or more MBs. DNG files are, of course, larger.
It is not so difficult to edit photos on the 9 Pureview. We did it with ease, and the results are astonishing. We did see some bugs and app might need some further updates, but when the review unit comes, we’ll further test that.
We did spend some time with the 9 PureView, not nearly enough to give some verdict about its camera performance or the phone overall. That’s why we do reviews. What is more fascinating about this device is a new way of imaging it brings to the market and all the possibilities it offers or could offer in the future.
During our time with the 9, we noticed smooth performance of the device in system tasks and similar stuff, which is probably absurd to mention, considering Snapdragon 845 is more than a capable SoC. The camera app was updated with new features to make more use of the 9’s camera. There is also an option in the settings that allows you to customize the camera app UI by changing the order of the icons or disabling icons of the features you don’t use. HMD is still experimenting with the camera UI, trying to find how to optimally arrange everything. We learned that a lot of UI changes are based on customer feedback.
In the Pro Mode, Nokia 9 PureView is capable of holding a 10s shutter speed. The ISO goes up to 6400, and the exposure is now measured in thirds. The settings change instantly as you move your finger in the camera UI and you can see the result on the viewport (from the central RGB camera as said before). Changing between photo, video, pro and other option takes some time. Taking a photo is practically instant, with the option to take burst shots and black-and-white shots as well. We took maybe 10 photos in a row without slowing the phone down and all of them being normally processed in the background, so there is no fear that you will miss a shot because of extra processing because you won’t. Moreover, in lowlight conditions it should be faster in snapping the picture than other phones, because of the monochrome sensors.
We also noticed that the phone got a bit warm after a longer use. I don’t want to jump to conclusion regarding heat emissions, because the phones are under heavy-load at MWC and only after a longer test period we can make some conclusions.
Regarding video, Nokia 9 PureView is capable of shooting video at 4K UHD resolution. The electrical image stabilization (EIS) only works with FullHD (1080p) and lower. The 9 PureView doesn’t have OIS for few reasons. While taking photos, OIS on camera lens is there to make sure the photo doesn’t get blurry when the sensor takes in more light. That’s why phones with great low-light performance, like the old Nokia Lumia 920 or 1520 had OIS. The 9 PureView has three dedicated monochrome cameras for that, so there is no need for OIS while taking photos, according to HMD. This is something that will be interesting to test.
The monochrome cameras also help in creating the depth map, something we covered above. If HMD opted for optically stabilizing some or all of the camera sensors (I don’t know what would be the best way to do it because I didn’t see anyone having OIS on monochrome sensors so I guess it would go on the two RGB sensors) the phone would become thicker and the camera system harder to manage.
The lack of OIS will most likely be noticeable in video. While video recording, Nokia 9 PureView uses the central RGB camera. If you’re wondering why doesn’t the device use all five cameras, it’s because the amount of data you will have to process in real-time is crazy and that would require a stronger hardware (not stronger in sense of Snapdragon 845 vs 855, but in the sense of a phone vs. Nokia OZO camera that sold for €30,000) and the camera algorithms stitching the feeds are also something that would need to be developed, because on OZO, you had 360 video, while the phone would still record a “2D” video.
Having OIS on the central camera for videos would be a great addition, but it would complicate the setup so much and require a new design. That it is a logical tradeoff considering Nokia 9 PureView is primarily bringing innovation in the photos department. That doesn’t mean that video from 9 PureView will be bad, considering the 649 euro price tag, it will most likely be great value for the money.
Overall, our first impressions from the Nokia 9 PureView are positive. After a long time, we see something really new in mobile photography segment. Keep in mind that the 9 PureView is the first device capturing photos in this novel way for smartphones. The device as a device for €649 should satisfy the needs of most higher end users, while the camera has the potential to be the best thing on the market. It’s important to say, that because of all of the processing power and engineering that went into the device, it might not be for users that want a point-and-shoot device to instantly share photos on social media. If you remember the original 808 PureView, it wasn’t for them either, right? But we know what happened after that, benefits of the 808 were ported in more compact forms and appeared on Lumia 920, 1520, 830 that offered great point and shoot experience. Considering the 9 PureView is also the first generation of new camera hardware, the logical way would be to make this new way of taking photos as mainstream as possible in the future, just what Nokia did.
We are very excited for the first reviews and in-depth camera comparisons of the 9 PureView with other devices. MWC wasn’t really ideal to do that because of different hardware and software builds floating around, restricted time and a big crowd wanting to play with the device. The posted photo samples and some photos we made are really promising, but for a final verdict we will have to wait for it to hit the stores, which is expected to happen during March, for a really good price of €649.
