官方建議Macro時，光圈縮到F4
http://www.finepix-x100.com/story/lens-2
9. One more challenge: 10cm macro performance!
In order to expand the camera's scope of applications, a macro capability is essential. However, the adoption of a lens that has both a "bright" aperture value and slim size makes exceptional macro performance especially challenging.
While adopting a focusing system of a fixed rear lens element group and an adjustable front lens element group, the lens has been designed to hinder the occurrence of "image plane error" when taking a macro shot. However, when shooting macro shots with an open aperture in the neighborhood of F2, spherical aberration tends to occur. It is therefore recommended that an aperture value of F4 is selected for macro applications.
