Hello, this is the second part of the blog about the development of the S-R2060. The four of us, Kitada and Kudo who were in charge of the optical design and Ichikawa and Matsukawa who were responsible for the mechanical design, will talk about our new lens product.

In this part, we will introduce the optical design for the suppression of focus breathing as well as the product design and operational ease.

As a company that develops and manufactures professional camcorders for the TV and movie industries, Panasonic boasts industry-leading video technology. We have positioned focus breathing (a change in the field of view resulting from the adjustment of the focus position) as a critical factor for video performance and have been working ahead of others in the industry.

o suppress focus breathing, the focal length of the focus lens group must be optimized during the optical design stage. For the S-R2060, we opted to configure the second zoom component with four lenses in order to give more flexibility for the optimization of the focal length. This enabled us to successfully optimize the focal length of the focus lens group without destroying the symmetry of the overall optical system. As a result, we have reduced focus breathing to a level that causes no problem even in cinema applications while appropriately correcting various aberrations generated by the entire optical system.

As part of improving the video performance, we also worked on reducing the operating sound of the focus unit and aperture unit during video shooting. Both units are driven by stepping motors operated by the high-precision micro-step control using smooth acceleration/deceleration profiles to realize quiet operation for comfortable video shooting.
In addition, the aperture drive (change of F value) control is smooth even if the brightness of the subject changes significantly or during panning in video shooting. This suppresses noise and sudden change of exposure.

As for the external design, we had to add a “constriction shape” on the outer circumference of the lens barrel as an icon of the S series concept and to improve the ease of operation. However, the zoom ring, focus ring and AF-MF selector switch had to be installed to the circumference of the S-R2060’s small lens barrel, so it was an extremely difficult task to arrange all of them neatly on the compact lens barrel without adversely affecting the apparent size or the ease of operating the rings and switch.
We produced multiple samples of the constriction shape with different ridge heights and width dimensions according to the external lens shape and checked the appearance and operational ease of each sample repeatedly to determine the optimally balanced constriction shape.

The rings must be precision-engineered since they are frequently used in all types of shooting situations, regardless of whether taking pictures or shooting a video. They must move smoothly when the user starts turning it as well as when the user continues turning. They must stop firmly when the user stops turning. Once the rings are positioned, they must not move accidently until they are operated again. Furthermore, the quality of operating feel is an important factor demanded by the customers.
Accomplishing all those requires the improved precision for the inside and outside diameters of each ring sliding section and their clearances as well as the strict selection and management of appropriate grease type, application amount and application method. With the S-R2060, we have achieved a high-quality, silky operating feel and high-precision operation by ensuring dimensional accuracy, by selecting the most appropriate grease specifications and by strictly managing them with the cooperation of the designers and the engineers at the manufacturing plant.

For the S series lenses, we design dust-/drip-proof specifications to allow the users to concentrate on shooting in the field and ensure low-temperature resistance to withstand even -10˚C to enable shooting in cold places such as on a snow-covered mountain.

In the dust-/drip-proofing, it is structurally more difficult to prevent entries of water and others through the gaps at the sliding sections than at the gaps between stationary parts. The water-proof sealing material attached to the gaps at the sliding sections could affect the operating feel and operating accuracy, so we carefully selected materials, ensured the dimensional accuracy of the sliding parts and strictly managed them in the same way as for the grease and its application locations.

There is a diversity of items to consider in achieving the resistance to low temperatures of down to -10˚C, such as resolution performance, AF performance, zoom tracking performance, aperture performance, durability, operating torque and operating feel. To extend the guaranteed lowest resistance temperature to -10˚C, we needed to examine a huge amount of data as compared to when the guaranteed lower-limit resistance temperature was 0˚C.

The AF performance and zoom tracking performance, in particular, must stay unchanged even when the temperature rises or falls. To fulfill this requirement, we have installed a temperature sensor in the lens and provided a temperature correction function that detects temperature and corrects the focus moving distance accordingly in order to prevent the performance deterioration due to low temperatures.

The S-R2060 not only has an attractive external design but also fits nicely in the hand and offers excellent functions and operability, not to mention the high durability. Every detail is meticulously designed to reflect the user’s intentions in the captured images.
The LUMIX S series aims to become a trusted partner of all creators. Its outstanding image quality and exceptional ease of operation help create masterpiece photographs and videos. Please try the S-R2060 and experience its true performance.