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234 Bu il d Y o ur O w n Q u a d c o p t e r

Model Pixels Photo Ultra Wide Medium Narrow Protune
(MP) Burst Wide
White 5 3 x x
Silver 11 10 x x x x
Black 12 30 x x x x x

Table 9.1 Comparison of Hero 3 Camera Versions

Several controls are multipurpose, which minimizes the total number of separate camera
controls. The Power/Mode button performs both activities that the name suggests: it powers
the camera on or off and selects a mode menu. The Shutter/Select button either starts or
stops a video; takes individual photos or photo bursts; and starts or stops time-lapse photos.
It also serves as a menu item selector in conjunction with the Power/Mode button, which
selects the overall menu to be used.
Figure 9.3 is a diagram of the back of the Hero 3 camera that shows several features,
including the important WiFi button, which only turns the WiFi on or off. All configuration
of the wireless channel is done through the menu system. There is also a blue LED on the
front of the camera that will flash if the WiFi link is on.
A Hero port that is available for plugging in certain accessories is also shown in Figure
9.3. A popular accessory is the LCD backpack, which is shown in Figure 9.4. The backpack
makes it possible for users to view their photos and videos quickly without using a computer.
The Hero 3 has a simple optical system that is made up of a lens with a very small focal
length, as shown in the Figure 9.5 diagram. This very small focal-length lens results in a very
wide field of view (FOV), which is specified in the Hero 3 documentation as 170°. A lens with
such an ultra-wide FOV is sometimes referred to as a fisheye lens, although the Hero 3 lens
does not have the same extreme distortion as a true fisheye lens. Figure 9.6 shows several
photos taken with a Hero 3 Black Edition in which this distortion is quite evident by the
curved horizon. Technically, the fisheye distortion is known as barrel distortion.
The two original sample photos have also been post processed by imaging software that
eliminates the inherent distortion. These photos are marked as “Corrected” in the figure.

Figure 9.1 GoPro Hero 3 camera.