The logo is based on the Golden Rectangle. The Golden Rectangle one whose side's lengths are in the golden ratio. A Golden Spiral is actually also a Golden Rectangle.In photography, we may unknowingly make relation(s) with the Golden Rectangle, where there has to be certain ratio for the longer side to the shorter side, this surprisingly turns out to be the Golden Ratio. The only way to construct the Golden Rectangle is to use a straight edged ruler and compass. First, you draw a square with the ruler. Second, you draw line from the mid-point of the side of the square to an opposite corner. Finally, use that line as the radius to draw an arc that is rotated on the same mid-point of the side of the square, which defines the height of the rectangle. Voila! The Golden Rectangle is complete. Therefore, the logo was created in such a form. The Circle is in front of the golden rectangle, which represents as a lens of the camera. Now, the logo looks like a camera which also holds the Golden Rectangle as its foundation. For more information about how the golden rectangle works in Photography and Art, please have a look at the following links

-The Golden Ratio

-How artists use it. (youtube video)

An image of the Rule Of Thirds in action. photo taken with Dp2 by Mijonju