Interview with S5II/S5IIX Developers
Bringing rendering performance to new levels in line with our picture-making philosophy of “Capturing it all”
Takayuki Tochio (Image Quality Design)
─ Does LUMIX S5II follow the LUMIX picture-making philosophy?
Tochio: When developing the Micro Four Thirds camera LUMIX G9, we established the picture-making philosophy of “Capturing it all” and assembled a project team comprising the image quality design team members and others with a passion for photography and video. That is where the phrase “Capturing it all” was born. We continued this picture-making philosophy with LUMIX S5II, and focused efforts on exploring what improvements could be made and what expressions were possible with the new engine and sensor.
─ What specific improvements did you make?
Tochio: Many factors make up image quality. The main ones are high resolution, rendering with a 3D effect and depth, and a rich color gamut.
To achieve high resolution, we incorporated new Intelligent Detail Processing in the new
engine. This delivers improvements such as smoothly rendering diagonal lines and edges. And by reducing overshoot in which fine lines outline the subject, it delivers a more detailed rendering of the subject.
To achieve a rendering capability that delivers a 3D effect even at high sensitivity, we focused efforts on rendering a 3D effect and texture by improving the texture of granular noise with the new engine and applying noise reduction while keeping a certain amount of granular noise.
For the color gamut, we designed the camera to reproduce healthy looking skin color in portraits as well as vibrant blues and reds, and render minute color information such as patterns on individual yellow leaves on trees. We also added a new color shading compensation function. If you attach an L-Mount lens, the camera will compensate for color cast around the angle of view with in-camera controls, but the color shading compensation function also reduces color cast with other companies’ lenses or old lenses, thus expanding users’ lens options.
─ What kind of function is the new Real Time LUT?
Tochio: We added Real Time LUT to LUMIX S5II. It allows you to apply color adjustments made with RAW processing and other tools to the live view screen, JPEG images, and video, all of these in real time. LUMIX already had a function that let you apply LUT in the live view screen with Log-format video to shoot imagining the final footage, but LUMIX S5II’s new engine enables you to apply your favorite LUT to not only the live view, but also to apply it and save as JPEG and video files. This lets you create photographs in the style of your favorite creator by simply purchasing their LUT and downloading it into your camera.
─ Is the new image sensor LUMIX S5 sensor equipped with Phase Hybrid AF?
Tochio: Besides phase detection, the image sensor itself has the same basic features, but we did change the structure of the hardware around the sensor. By optimizing the structure of the analog electronic circuitry and power supply, we improved stability and uniformity of screen images even at high sensitivity.
─ Tell us about the improved 3D noise reduction.
Tochio: 3D noise reduction is a video technology that adjusts the degree of noise reduction by distinguishing between moving and still parts. If you apply noise reduction to moving parts, you sometimes get an afterimage, but the new engine improves the accuracy of distinguishing between moving and still parts for more effective noise reduction.
Taking both image quality and autofocus to the next level in pursuit of a new standard
Mitsutaka Nakamura (Development Leader)
─ This is the first in the LUMIX series to have phase detection autofocus. Why had you been using contrast autofocus so far?
Nakamura: Image quality is a top priority in the LUMIX series. Previous models in the series have received high praise for their image quality.
Using phase detection autofocus unfortunately causes pixel loss. Since we won’t compromise when it comes to image quality, the approach we took in development was enhancing autofocus as much as possible while ensuring the best image quality. That’s why we worked on improving contrast autofocus with Depth From Defocus (DFD) technology so far.
─ What led to LUMIX S5II being the first LUMIX to have Phase Hybrid AF?
Nakamura: We had employed contrast autofocus in combination with DFD technology, but we listened carefully to the needs of the market to improve the autofocus capability and continuously deliberated on what the best autofocus system would be. In addition, the image processing technology for pixel loss correction of the new engine enabled us to achieve our target level of image quality, allowing us to implement phase detection autofocus.
─ LUMIX S5II has two UHS-II card slots. Were there a lot of requests for that?
Nakamura: LUMIX S5 had two slots also, but one was UHS-I compatible and the other UHS-II. Some said that it was confusing since their performance was different but they looked the same, so we made both slots UHS-II compatible in the LUMIX S5II. CFexpress was another option, but the cards are more expensive and larger than SD cards, and also produce more heat. We decided on SD cards because they were the best overall fit for LUMIX S5II. All video recording modes support SD cards’ write speeds, the cards are widely available, they are sold in convenient set sizes, and so on. LUMIX S5IIX video recording modes have a higher bit rate, so some modes are incompatible with SD cards, but it is compatible with external SSD drives via USB.
─ Did increasing the buffer memory lead to any changes, such as in the number of frames in burst mode?
Nakamura: We greatly revamped the system for LUMIX S5II, including engine and memory structure. It has four times the memory of the LUMIX S5. We also improved the engine’s processing power and greatly increased the number of frames in burst mode. Specifically, LUMIX S5’s RAW+JPEG mode could capture 24 frames or more, but the LUMIX S5II can capture over 200 frames or more under the same conditions—that’s around eight times the amount—allowing you to shoot continuously without stress. We also added Phase Hybrid AF and enhanced tracking performance above previous models. Performance has been improved considerably, allowing users to actively shoot moving objects. For example, the electronic shutter enables high speed burst shooting at 30 frames per second, and rolling shutter distortion has been reduced.
─ Tell us about the viewfinder.
Nakamura: The LUMIX S5 viewfinder was a 2.36-million-dot OLED panel with 0.74x magnification, but the LUMIX S5II has a 3.68-million-dot OLED panel and newly developed optical system. This increased the magnification to 0.78x, making the image larger and easier to see. We also focused efforts on the optical performance to improve the level of correction against eye movement when you look away briefly and distortion around the subject.
Incidentally, we moved the eye sensor to switch between the viewfinder and rear LCD screen from the bottom to the top in response to feedback from some users that errors occur when rain or snow falls on the sensor.
─ What about video recording did you enhance?
Nakamura: Video capability is a top priority in developing LUMIX cameras, and many models have received high praise from users. With the LUMIX S5II, we increased performance while making sure to keep it the same size and price range as standard full-frame cameras. We evolved the video recording modes from the previous LUMIX S5 model to support 6K 30p and 4:2:2 10-bit 4K 60p recording. In addition, installing a small cooling fan enabled the camera to deliver unlimited recording time in most recording modes, including 6K 24p and 4K 60p, without altering the size.
It boasts performance that is on par with high-end cameras and even better in some areas like autofocus, so we hope it is enjoyed by a wide range of people.
─ Besides 4:2:2 10-bit video, LUMIX S5II also supports 24-bit audio.
Nakamura: We have always focused our efforts on audio too, as we realize it is nearly as an important part of video as picture quality. We developed LUMIX S5II with the intention of having a wide range of users use it. The sound quality of the built-in microphone has the same signal-to-noise ratio as a relatively inexpensive external microphone, so you can enjoy good sound quality even when taking video with just the camera.
And for those seeking even greater video and audio quality, it supports data-rich 4:2:2 10-bit video and 24-bit audio, ensuring no glitches in video or audio when editing.
Interview with S5II/S5IIX Developers