Compared to its predecessors, many changes have been made to the EOS 7D Mark II, the first revamped model in five years. This article is an interview with the developers to obtain first-hand information on the technology of the EOS 7D Mark II, and to find out more about the appeal of the camera. (Reported by: Ryosuke Takahashi)
Q: What are the most distinctive features of the new image sensor?
"It boasts a high resolution of about 20.2 megapixels, and a basic ISO speed range from ISO 100 to 16000 (expandable to ISO 51200). Also, it supports a maximum continuous shooting speed of about 10 fps and Full HD (50p and 60p) movies. AF can also be performed by the Dual Pixel CMOS AF."
Q: What is the low-light sensitivity limit of AF?
"The low-light limit is -3EV at the f/2.8 centre AF point (during One-Shot AF)." For ease of comparison, the limits are -0.5EV on the EOS 7D and -2EV for the f/2.8 centre AF point in the case of the EOS-1D X and EOS 5D Mark III. The EOS 7D Mark II also outperforms these models at the peripheral areas of the image.
Q: Is the Dual Pixel CMOS AF compatible with all the EF lenses in the market now?
"Yes, the Dual Pixel CMOS AF is able to function with all the existing lenses in the market. Information on incompatible lenses is available on Canon's website." Note that Canon does not guarantee the operation and use of third-party lenses with the Dual Pixel CMOS AF.
Q: How are the vibrations caused during high-speed continuous shooting reduced?
"The mirror is driven by a motor (spring-driven in the case of the EOS 7D), and the collision energy is reduced by controlling the driving speed. Also, a mechanism for absorbing mirror bounce instantly is employed, and a new mass damper has been adopted for the sub mirror."
A: Shutter Charge Motor Unit
B: Bounce Prevention Mechanism for Sub Mirror
C: Main Mirror
D: Mass Damper for Sub Mirror
E: Bounce Prevention Mechanism for Main Mirror
F: Drive Lever Unit for Main Mirror
G: Mirror Drive Motor Unit
Q: What are the technologies that made the maximum speed of approx. 10 fps achievable?
"High-speed continuous shooting at up to about 10 fps is achieved through a combination of technologies, such as the newly-designed shutter unit and mirror drive mechanism, high-speed signal readout from the CMOS sensor, and high-speed image processing by the Dual DIGIC 6 processors."
Q: Is the release time lag on par with that of the EOS 7D?
"The minimum release time lag when the shutter button is half-pressed is about 0.055 second (approx. 0.059 second in the case of the EOS 7D)." With a shorter shutter button stroke, shutter can now be released by touching the shutter button lightly and applying force on it.
Q: What is digital compass?
"It is a function that appends information on the direction the camera is facing to the image." A device for detecting direction in built into the rear of the camera (to the right of the Quick Control Dial), which records the camera's orientation in the image. This, added with the GPS information, allows easy identification of the current position.
Q: Is the performance of the Dual Pixel CMOS AF equivalent to that of the EOS 70D?
"In addition to a higher focusing speed, improvements have been made to drive the lens smoothly even for subjects that the EOS 7D has difficulty in capturing, such as subjects with a low contrast." While the two models operate under the same principles, detailed enhancements have been made, which contribute to the more stable operation of the EOS 7D Mark II.
A: Area Covered by Dual Pixel CMOS AF
B: Each of the effective pixels is made up of two photodiodes
Phase-difference AF is possible within about 80% (vertical) x 80% (horizontal) of the shooting screen
Q: Can you explain more on the EOS iSA system?
"It is a high-precision system for controlling exposure by detecting subjects using the newly-developed RGB+IR (infrared) metering sensor with about 15 megapixels." Information is transmitted from this system to EOS iTR AF, for instance, to help with automatic detection or switching of the AF point.
Born in Aichi in 1960, Takahashi started his freelance career in 1987 after working with an advertising photo studio and a publishing house. Photographing for major magazines, he has travelled to many parts of the world from his bases in Japan and China. Takahashi is a member of the Japan Professional Photographers Society (JPS).
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