The camera on the brand new OnePlus 9 Pro smartphone isn’t just exciting for the Hasselblad tie-up, there is also a lot of potential in play because of the new Sony IMX 789 sensor and the Qualcomm Snapdragon 888 chip that work together to provide a new photography experience.
Some of that tech might seem a bit geeky at first blush, but delving beneath the intimidating layers of jargon reveals some fascinating new technology.
What is the IMX789?
Sony’s IMX789 is a new smartphone camera sensor that’s designed to take full advantage of the image processing capabilities of new chipsets like the Snapdragon 888 powering the OnePlus 9 Pro. The additional horsepower of that SoC paired with this sensor is what allows the OnePlus 9 Pro to record 4K 120fps and 8K 30 fps video. We’re talking image processors (ISPs) that can handle the processing load of a gigapixel of image data per second. Most 4K cameras only handle a quarter of that load.
A new autofocus system
The better smartphones and cameras out there tend to use a system called phase-detect autofocus (PDAF) to focus within a scene. For PDAF to work, several hundred or thousand specially-designed points on the sensor will look at a scene from two different perspectives – much like our eyes do – and use complex math to figure out how to focus.
Traditionally, these phase-detect pixels are minuscule compared to the regular light-sensitive pixels of a camera sensor. This makes these sensors less sensitive to light and so unable to work properly in low light.
Sony’s approach, called 2×2 OCL (On-Chip Lens) uses the same principle that makes PDAF work – observing an image from different perspectives – but in a way that utilises the entire sensor and not losing light sensitivity.
In modern smartphone camera sensors, each pixel is covered by a microscopic lens called an OCL. This lens directs more light into each pixel, increasing its sensitivity. Sony’s 2×2 OCL approach covers sets of four pixels (in a 2×2 grid) by one lens, effectively allowing every pixel to observe an image from a different perspective. This approach also improves colour quality and light sensitivity, especially in pixel-binned images.
Dual-native ISO to reduce noise
Every camera sensor has at least one native ISO as determined by the design of the sensor and the amplification circuit. If you think of the sensor as a mic and the ISO as gain, you can boost the light sensitivity of a sensor much as you would the volume sensitivity of a mic by increasing gain.
When you increase gain, or ISO, background noise is also amplified, which is why you see noise in images shot in low light, and hear noise (hiss) from overly boosted mics.
As with gain on mics, each sensor has an ISO sweet-spot where noise is minimal and light sensitivity is optimal. This sweet-spot, however, is usually biased towards daylight shooting. A dual-native ISO, as in the case of the 9 Pro’s sensor adds an additional electronic circuit that provides a clean image at a higher ISO.
The result? Better noise control and cleaner images in low light. Dual-native ISO is more complicated to implement, and more expensive, which is why very few cameras actually implement the feature.
Ghost-free HDR or DOL-HDR
Traditional HDR techniques require that a camera take multiple images in a quick burst and stack them together to improve the dynamic range (the difference in intensity between the darkest and brightest parts of an image) of your shot.
The problem with this approach is that there’s a time delay between each frame, which is a big problem when your subject is moving (a car or the arms of a person waving, etc.). When these images are stacked, they will not be perfectly aligned, and unless the camera does some very fancy and intelligent stacking, your subjects will have ‘ghost’ trails following them.
DOL-HDR (Digital OverLap High Dynamic Range) does things differently. Instead of taking multiple images, the sensor captures multiple exposures while reading sensor data. This happens nearly instantaneously, resulting in no motion blur or ghosting. This is not a new technique, but it’s nice to see it implemented in a new sensor.
The math is very complex, but essentially, a 12-bit RAW can record one of over 68 billion shades per pixel. Most LCD displays can render 8-bits of colour per pixel (16.7 million shades), and premium phones like the OnePlus 9 Pro can render 10-bits of colour per pixel (1.07 billion shades)
12-bit is clearly overkill. Why would anyone need to record 68 times more colour than your display can render?
Well, if you’re shooting RAW, you’re looking to edit your images. And when editing images, you’re going to need all the excess data you can get. Not only does 12-bit RAW give you 68 billion colours to play around with, it also gives you additional dynamic range, which you can use to push or pull the colours in your image as you see fit without noticeable colour artefacts or loss in detail.
Ultra-wide: Distortion-free 50 MP images
The 50 MP camera on the OnePlus 9 Pro is special. The 50 MP IMX 766 sensor is one of the largest we’ve ever seen in an ultra-wide, and also one of the least distorted.
The large size will give you images that are relatively clean and noise free, with better bokeh and background separation. The lack of distortion, a result of using a mathematically corrected, digitally surfaced lens, will keep straight lines straight, allowing your ultra-wide shots to seem more natural.
Ultimately, the image you get must look pleasing to your eye. While each person perceives colours differently, there are some rules that are universal. Muted contrast is great for shots of people, for example, high contrast is great for black and white, and punchy colours are great for nature photography, and so on.
When processing an image, a camera system must determine which approach is best and deliver a result that is optimised for the scene that was shot. This, grossly oversimplified, is what colour science is all about.
The DJI-owned Hasselblad brand is well-known amongst pros, and for the very natural colour tones that its cameras and colour science produce. The OnePlus-Hasselblad tie-up is meant to replicate that colour tone on the 9 Pro camera.
Together, these features and new hardware make for a compelling new camera system. That being said, it’s you, dear reader, who will determine the fate of these new cameras and guide the development of future systems.
All the tech in the world will not save an image that you don’t like. Love it or hate it, we’d love to hear your thoughts on the OnePlus 9 Pro’s new cameras.