After I use effect "size of feather region" in any object (photo or picture) and I export it into pdf file, the result is the object I applied the effect is without any feather region. I tried do this in high resolution pdf (300 dpi) and screen resolution and the result is the same - no effect.
I have got Graphic Designer 2013, Acrobat Reader XI and Radeon dual graphic card. I use windows 8.
P.S.
This same situation is with Romboidal gradient - darker mode.