Samsung announced (in conjunction with Xiaomi) that they have made an 108-megapixel 1/1.33-inch camera sensor that will soon be found inside of cellphones. At first glance it sounds absurd. What kind of image quality could it possibly have? How ugly will it be above base ISO? How much resolution do you really need for social media posts? But there are some interesting innovations that might someday be applied to Fujifilm cameras, so let’s take a closer look.
How this new sensor directly relates to Fujifilm is that it’s an ISOCELL Plus sensor, which requires a materiel developed by Fujifilm, and only Fujifilm has this material. What Samsung did with it is develop a sensor that has less “cross talk” between pixels, which improves color accuracy, dynamic range, high-ISO capabilities and fine-detail rendering. Essentially, it allows smaller pixels to perform similar to larger pixels. You can put 108 million teeny-tiny light sensitive sensor elements on a small sensor with ISOCELL Plus, and it will perform similar to 108 million larger-but-still-quite-small light sensitive sensor elements on a little bit larger sensor without this technology. Whether the lens will be able to resolve that much detail, as it will need to be a heck-of-a-sharp lens, remains to be seen, but if it can, that would be quite the leap in cellphone camera technology.
I used to have a Nokia Lumia 1020 cellphone, and the phone itself wasn’t especially great, but the camera, with a 41-megapixel 1/1.5-inch sensor and Zeiss lens, was surprisingly good. Well, sort of. It had a very narrow margin, as you needed to stay close to base ISO, and the dynamic range was small, but in the right situations it delivered stunning pictures that you’d never guess came from a cellphone. I have no idea if Xiaomi’s phone with the new 108-megapixel sensor will be similar or not, but it might be, and it might even be better.
Aside from ISOCELL Plus, the other interesting innovation from Samsung with this sensor is quad-Bayer array. Instead of the typical two green, one red and one blue Bayer square arrangement, this has a four green times two, four red and four blue square arrangement, with the four pixels of the same color next to each other in a square. The idea is that the four same-color pixels can be merged through software into one pixel, turning the camera into a 27-megapixel traditional Bayer array. Why wouldn’t Samsung use larger light sensitive sensor elements and set the megapixel count at 27? Why do this weird tiny-pixel quad-Bayer pixel-merge thing? Well, it allows software to do some interesting tricks. For example, it can capture up to four independent 27-megapixel exposures simultaneously and blend them together, extending dynamic range, reducing noise, and/or increasing high-ISO capabilities. Or, if the dynamic range doesn’t need extended, and the noise doesn’t need to be reduced, and the ISO doesn’t need to be increased, it can produce a very large fine-detailed full-resolution picture.
Slowly the technological advancements of the small sensor world trickle up to larger sensors, and someday a version of ISOCELL Plus and pixel-merge could very well be found in Fujifilm cameras. What might this look like? If you were to take this same Samsung chip and increase it to APS-C size, it would have roughly 216-megapixels, and would deliver a pixel-merged 54-megapixel image. I’m sure, however, that there would be a reduction in noise performance, dynamic range and high-ISO over current X-Trans sensors, and, even with the excellent Fujinon lenses available, the question of whether that much detail can be resolved would still need to be answered. What I see more likely to happen is sensor elements being used that are twice as large as those on the tiny Samsung chip, and an APS-C sensor with 108-megapixels produced, which could be pixel-merged to 27-megapixels. I’m not 100% sure, but I believe a quad-X-Trans array is possible. Essentially, it might be feasible to have nearly identical resolution as X-Trans IV, but with improved dynamic range and high-ISO capabilities, and the option for full-resolution 108-megapixel pictures when the ISO is under a certain amount (say, ISO 640). It’s still questionable whether or not Fujinon lenses can take advantage of that much resolution, but even if it is “only” able to produce resolution equivalent to 50-megapixels, that’s still double what it is now. If ISOCELL Plus and pixel-merge ever do come to Fujifilm X, it could very well be a game-changer type of thing. Or perhaps the required processing power and heat dispersion are too difficult to overcome, and it never makes its way to larger sensor cameras. Time will tell.