Mobile phone cameras are about to get a significant performance boost.
Sony on Monday introduced a 48-megapixel sensor for cellphone cameras that measures less than one-third of an inch diagonally. The sensor is slated for release in September.
To pack that many pixels into such tight quarters, Sony had to shrink their size to 8 microns. Shrinking pixel sizes usually results in performance degradation, not improvement. It usually results in poor light collection and a drop in saturation sensitivity and volume.
“With traditional sensor architecture, the pixels get so small that they pick up a lot of noise, so the pictures aren’t as good as sensors with fewer but larger pixels,” David D. Busch, creative director of the David Busch photography guides, told TechNewUK.
Better Digital Zooming
However, the new sensor is designed and manufactured with techniques that improve light collection efficiency and photoelectric conversion efficiency over conventional products, Sony said.
The smaller pixel size makes the sensor suitable for many mobile phones.
“Any component that fits into current hardware design trends, like thin bezels, will be attractive to OEMs,” noted Gerrit Schneemann, a senior analyst with IHS Markit.
Meanwhile, the large number of pixels enables high-definition imaging, even on smartphones that only have digital zooms.
“Having that much pure resolution opens up more options when it comes to a digital zoom, as opposed to optical zoom, which happens in the lens,” said Stan Horaczek, technology editor at ST hint.
“Digital zoom happens by basically cropping in on an image as you capture it, rather than in post capture,” he told TechNewUK. “More megapixels help for that, because the system doesn’t have to guess what details should look like.”
‘Amazing Product’
The new Sony sensor is an “amazing product,” said Kevin Krewell, principal analyst at Tirias Research.
The sensor blends a 48-megapixel super resolution mode with a lower resolution mode that offers high sensitivity for low light conditions, he explained.
“The 48-megapixel mode, combined with a precise lens, will offer very detailed pictures,” Krewell told TechNewUK. “The smaller area for each pixel will limit the amount of light those pixels receive, but the quad-pixel, low-light mode addresses that limitation.”
Sony works its low light magic through something called the “Quad Bayer color filter array.” In low light conditions, that technology allows the signals from adjacent pixels to be added together, effectively doubling their sensitivity.
“Sony is combining four smaller pixels into one in order to improve resolution in low light circumstances. Overall, this is a proven, sensible approach to solving a common problem,” observed Charles King, principal analyst at Pund-IT.
“Huawei is another OEM utilizing this type of technology to increase low-light performance,” IHS’ Schneemann told TechNewUK. “Subjectively, this has worked for Huawei. It remains to be seen if Sony can deliver as well.”
Manipulating pixels may have some tradeoffs, however.
“My guess is that when they group smaller pixels to form larger pixels, they may be able to smooth over the noise in the image, but there may be loss of sharpness in the details,” said freelance journalist and photographer Terry Sullivan, a former associate editor for digital cameras and imaging at Consumer Reports.
“It will also affect dynamic range,” he told TechNewUK. “Details will be missing from lightest highlights and darkest tones.”
‘Pixel Wars’
Sony’s sensor can deliver dynamic range results that are four times that of conventional products, according to the company. What that means is that even scenes with bright and dark areas can be captured with minimal highlight blowout or loss of detail in shadows.
“If the new sensor has four times better dynamic range than conventional sensors, that suggests that performance in both full and low-light modes should be outstanding,” Pund-IT’s King told TechNewUK.
During the age of the “pixel wars,” when megapixel count was a major selling point for both phone and camera makers, a 48-megapixel sensor would have drawn a lot of attention. That’s less so today.
“Today, the traditional association between megapixels and printing quality no longer has a lot of significance,” noted Ross Rubin, principal analyst at Reticle Research.
However, there are some advantages to higher resolution, he said.
“When Nokia came out with the 1020, which was a 40-plus megapixel camera , they touted its high resolution as a substitute for an optical zoom,” Rubin told TechNewUK.
Red Meat for Marketers
When the new sensor starts to hit the market, it most likely will appear in high-end phones.
“Shooting pictures in 48-megapixel mode will use up more storage and will require an applications processor with high-performance image processing, which should limit it to the high-end phones,” Krewell said.
“That said, it will likely kick off another round of pixel wars,” he added.
Whether a new round of pixel wars starts or not, that 48MP number will be red meat for marketers.
“I think both sensor makers and handset OEMs will view this as an opportunity to stand out with a headline-grabbing hardware spec,” Schneemann said.
That said, “I am not convinced that this will necessarily shift the overall market in a significant way, where consumers abandon one brand over another, because of more megapixels,” he continued.
“The output of the sensors is subjective for consumers, and the implementation of a sensor by each OEM varies as well,” Schneemann pointed out. “The Nokia Pure View and 1020 both hit 40 megapixels, but that did not impact the fate of Nokia’s smartphone business materially.”
King of Megapixels
Sony will hold the leadership position in the megapixel category for some time to come, said Ken Hyers, director of emerging device technology research at Strategy Analytics.
“Most smartphone vendors aren’t going for a huge number of megapixels,” he told TechNewUK.
Only 2.5 percent of smartphones shipped this year will have 20 or more megapixels, Strategy Analytics has forecast.
“The sweet spot this year is at 12 to 15 megapixels,” Hyers said.
That may change, though, as resolutions of smartphone displays increase.
“We might start seeing smartphone companies pushing resolution up as the future of high-res screens looms,” Popular Science’s Horaczek said. “Filling an 8K screen takes something like 33 megapixels, so more image data is probably going to be the order of the day.
