The newly developed super-telephoto zoom lens "HD PENTAX-D FA 150 - 450mm F4.5 - 5.6ED DC AW" that is designed compactly for easy handling, but offers high imaging performance and toughness as well as super-telephoto coverage with 3-times zoom ratio. Interviewing a developer about the circumstances surrounding the birth of the product, thoughts put into it, and its appeal.
TETSUYA IWASAKI Manager of the Second Product Planning Section, Product Management Department
It has much less chromatic aberration than ever before, thus especially achieving a substantial reduction of color deviation that is likely to occur in the depth plane with respect to a subject. Also, in order to overcome typical usability issues such as the focus adjustment and focusing speed of super-telephoto zoom lens, four AF buttons are arranged on the lens body. Multiple functions assigned to the respective AF buttons and a combination of those AF buttons with the release button on the body side provide more stable AF operation and better hold of the lens. For instance, capturing a moving object in the distance, you can take a photo of the object closed up in an eye blink, using the focus preset mode. Thus, I can tell the lens is highly compatible with photographing of wild birds.
Conventionally, the lens design team and the lens body mechanical design and planning team advanced development projects, but the body development team and the UI (User Interface) development members have been more involved in the development of this product than ever, and considerable time has been taken to develop the product. By so doing, regarding the lens's "ease of use" in terms of, for instance, communication with the body and the operational performance when it is installed on the body, I think we have been successful in advancing the development from the diversified perspectives. For example, the AF buttons, extensively laid out, were developed with handheld usability in mind. Thanks to its compatibility with the body, it delivers the seamless operational performance regardless of whether the camera is in a vertical or horizontal position, enables a firm grip to prevent camera shake, and achieves a weight and rigidity balance. Our original intentions were to eliminate the inconvenience of changing the grip to press an AF button, but their finished layout happens to be such that it matches any camera shooting stance regardless of whether the user is left- or right-handed.
At the onset of the development of the lens, we made a simple mock-up of the lens with 3D printing. Based on the mock-up, we determined things such as the position of the center of gravity, checking of balance, the lens-holding position and the button positions. We have actively introduced 3D printing into our development process from early on, which made us possible to pursue the development of easy-to-use products taking into account detailed points, such as material layouts and switch distances, by confirming accurate mock-ups early on in the development process. There is a long-standing motto of the development team which says "Do not worry over your idea, but cast it into shape first."
According to the motto, we have been engaged in manufacturing centered on the modeling of products in parallel to the analyses of them on PC. As a developer, it is impressive to see an idea that takes shape from nothing and is eventually turned into a commercial reality.
As well as improved optical and operational performances, user benefits are extensively incorporated into the product. The benefits include the lock lever that prevents the zoom mechanism from extending spontaneously under its own weight or from "falling by its own weight" while you are carrying the camera with the lens attached, and a newly developed tripod that can be attached and removed easily. I hope the lens features everything one could ask for and can enhance convenience for users.