The original lens apertures are still operative, so you can still shoot at f/2 (although, as with the original lens, the sharpest images will come in the f/4 to f/5.6 range). Either the optical or the electronic viewfinder can be used, and even close-focusing produces sharp, clear images with no loss of acuity. You can still use RAW files and shoot with Motion Panorama 360. Even the lovely bokeh of the X100 is undisturbed. Using the built-in flash can cause vignetting, so the use of an external flash is recommended. The included lens cap fits the 49mm diameter of the conversion lens, as does the optional PRF-49S protective filter. For optimal aberration control, X100 firmware must be updated to version 1.3.0 or later.