Obata: The appeal of "Tensile Skin" design falls flat, so to speak, if you try to express it in two-dimensional drawings. Draw only the silhouette, and you'll fail to define the curved surfaces in 2D. That's why working with an expert 3D modeler is essential.
We kept in touch with a modeler during design, as I worked on the α77, and Takatoshi, the α65. We sought flowing, uninterrupted ridge lines, but at the same time, we had to consider optimal positions for each button and dial. Reconciling these conflicting goals was very difficult. We also had to attend to external seams and bulges around buttons, among other details, to bring the "Tensile Skin" concept to life.
Nakamura: In contrast to the midrange α77, the α65 is positioned as an entry-level model. Consumers in this segment include many seniors and women-people who benefit from a smaller camera body. Although smaller, the α65 would still need to share traits with the α77 and look consistent with the series. This was a task of mine.
Making products smaller adds to our work in design. It proved especially difficult with our "Tensile Skin" approach, in which organic curved lines and surfaces form an uninterrupted whole, because chiseling away a surface to make the camera smaller immediately throws off the natural balance. With this approach, we couldn't take any liberties or use any visual tricks, so after each minor adjustment, we had to reexamine the overall appearance. But once we had created an elegant surface, it made the body look nicely condensed, as if the surface were drawn inward. We refined the contours repeatedly to take maximum advantage of this effect.
Obata: A hallmark of "Tensile Skin" design is its sumptuous curves, but if they looked too glossy, it would cheapen the appearance. Adding a textured finish was a way to avoid this.
In these models, I also tried to tone down the glossiness of the grainy texture as much as possible. Toning down the highlights would reveal the beauty of the "Tensile Skin" contours without any distracting glare. On the other hand, a finish that's too matte would blur the contours and make surfaces seem flat. Determining just the right level of muted satin finish took careful study. Ultimately, the finish was expanded to a lens (DT 16-50 mm F2.8 SSM) and to the α65, which ensures both consistency in the series and a sense of luxuriousness.
Obata: As with the "Tensile Skin" styling, we wanted the grip to signal the direction we're taking and the feeling you can expect from a Sony grip.
On the back, new α (alpha) models feature an OLED viewfinder that captures subject nuances and conveys color information superbly, and we optimized the shape of the grip for stable viewfinder shooting. First, notice the ridge on front, between where your index and middle fingers rest. The ridge is absent on other models with live previewing, such as the α550, to give your hand a greater range of freedom when shooting. Here, we added the bump for a better fit as you wrap your fingers around the grip.
Another thing you'll notice is on the inner surface of the grip. The area where your fingertips would usually touch has been hollowed out, so it's concave. Your fingers wrap around the grip securely, so the camera stays steady both in viewfinder shooting and video shooting. And when you walk with the camera in your hand, you'll see it's a practical shape that helps keep your fingers around the grip.
Nakamura: In the α65, we sought to match the fit of the α77 by condensing the essence of the Sony grip for a smaller model. We wanted a secure grip even for women with smaller hands, so that people would be comfortable shooting with longer lenses. Toward this end, we analyzed and gained a better understanding of what makes up a Sony grip, and then applied our knowledge in the shape. A ridge to rest your middle finger against, and indentations to accommodate your fingertips: keeping these elements in mind helped us match the comfortable grip of the α77. Fortunately, we could conduct usability tests as we were testing the α77 grip, so we could compare people's impression of how they felt and how easy they were to hold. We also gathered data on the correlation between hand/finger size to a secure grip. This work supported objective analysis of key points in design, which made us confident of our choices.