The Panasonic S1R has joined the full frame mirrorless camera club, with an extraordinary 187 megapixel high resolution mode. I’ve had a look and share my thoughts.
The S1R is really a 47 megapixel camera. To create an image of 187 megapixels, a series of eight images are captured with the sensor shifted by half a pixel between images, the data is processed in camera to generate a massive 187 megapixel raw image, as well as a regular 47 megapixel image in case things go wrong, if enabled. Because the image is merged from several captures, the high resolution mode will only work properly with a very steady camera (tripod needed), and preferably with a static scene. There’s also a mode (mode 2) which allows for movement in the scene by selectively ignoring differences caused by movement and continuing to process the files with the remaining data, which reportedly works quite well in some situations. Here I’ve tested mode 1, which is intended for static subjects. The camera takes around 15 seconds to process the high res image after the 8 captures, so don’t expect to shoot quickly.
Since I’ve only tested static scenes, and the static mode, I can’t yet say whether the high resolution mode is suitable for landscape scenes with movement, I suspect they would be a bit hit and miss, or situation dependent, I’ll be interested to find out more.
The pixel shifting for high resolution achieves two goals. Firstly, the half pixel movement effectively increases the resolution of the image by capturing information in between each pixel location, and secondly, since the S1R uses a regular bayer sensor where each photosite records either red green or blue (not red, green and blue), shifting the sensor allows each pixel location to capture complete red, green and blue data. This is similar to the advantage of Sigma’s Foveon sensors, which by design already capture full red, green and blue data at each photosite, noticeably increasing the edge detail by eliminating guesswork when the raw data is processed.
I needed a comparison, so as usual the 45 megapixel Nikon D850 is my benchmark, the S1R’s sensor is almost identical in resolution to the D850. Surprisingly for a mirrorless camera, the S1R body is DSLR like in size, and larger than every other full frame mirrorless on the market, so the D850 and S1R can feel very similar to handle in terms of size and weight.
Until making this comparison, I was unsure exactly how much could be gained by increasing the sensor resolution, since there’s only so much detail a full frame lens can resolve. So for this test I’ve tried to keep the lenses equivalent and as high quality as possible, I’ve used Panasonic’s 50mm F/1.4 prime lens on the S1R, and a Sigma Art 50mm F/1.4 prime on the Nikon. I’ve had to stick with a Panasonic lens for the S1R, and the options are currently quite limited.
As of today, the highest resolution full frame sensors sit at around 50 megappixels, and there’s been no doubt in my mind that with the best lens’s fitted, even a 50 megapixel sensor is the weak link in the system, and usable resolution beyond 50 megapixels should be possible. It’s really a question of how much further can the full frame format be pushed. With the weaker optics of most zoom lenses though, 50 megapixels does seem to be pushing the boundaries. I’ve suspected this after inspecting images captured with really nice glass, where I often find edge detail showing false colour or moire patterns which aren’t a product of the lens, the lens is resolving the edges but the incomplete mix of red, green and blue photosites on the sensor doesn’t allow a proper colour rendering, causing the edge moire. The S1R solves this using the high resolution mode, at least for scenes without movement.
Onto the testing….
Here I’ve photographed a Melbourne laneway.
Near the center of the frame, the S1R shows the high resolution mode can in fact resolve details not possible with a static 50 megapixel sensor. The detail in the text, and even the brickwork is higher from the S1R’s high res mode (187mp) than the D850 or the S1R at native resolution (~50mp). There are however some movement effects in the foliage caused by the direct merging of 8 photographs (in mode 1). At native resolution, the results are very similar between the D850 and the S1R.
The crops below also show an interesting effect in the horizontal pattern at the lower right hand corner. Only the high resolution S1R image correctly renders the detail, the D850 and S1R at native resolution show false colour and patterns. Errors are caused by the interpolation of sensor data at fine edges, which is typical of today’s high resolution sensors and fine edge detail. These edge artifacts aren’t normally problematic because the details are so small, but if you’re chasing fine detail, they can make a difference. I found similar results with the rendering of fabrics, where the higher resolution S1R image resolves detail that would otherwise appear smooth at 50 megapixels.
In other images I compared the performance away from the lens center and the high resolution mode still proves helpful, but the detail falls off towards the edges as you would expect, and I’m seeing a much less noticeable difference there. In terms of actual detail captured, 187 megapixels seems a little overstated, perhaps 100mp is a closer fit for the scene center, either way, it’s a significant step ahead of the current 50mp cameras if you’re in a situation where it can be used, and you’ll definitely need good glass paired with it.
Fortunately, adapters are becoming available for different lens’s and the highly capable Sigma Art line will be released as a direct fit to the L mount before long. To me, the S1R offers an alternative to the volume sellers from Canon, Nikon and Sony if you’re after resolution. Though, I suspect and hope it won’t be long before the other manufacturers offer a usable high resolution mode as well, so watch this space. (Update July 2019: Sony releases 61MP A7R IV with pixel shift, I’m sure others will follow soon enough, meaningful differences between systems will be in the details and usability, not just the numbers).
Any initial doubts of the S1R high resolution mode have been pleasantly erased. While it’s not a perfect solution, it’s certainly desirable for some applications, and show what’s possible from the full frame format.