Aperture setting for swc

Submitted by Gabe Lee on Wed, 09/10/2008 - 04:10

Am new to this forum and just brought a second hand SWC. Tried to set the Aperture to 4.5 but can't turn beyond between 5.6 anf 4.5. Is there a trick to switch it? I tried to press the cross coupling release to change the Aperture but still can't set to 4.5. Please advise if this lens is having a problem. tks