N Ng Yu Lun New Member May 26, 2013 14 0 0 Mar 21, 2015 #1 Hi, I just brought a 17-40mm L f4 USM and realize when I look thru the lens (not the viewfinder) the hole doesn't seem very round {circular} in shape. May I know is it normal.
Hi, I just brought a 17-40mm L f4 USM and realize when I look thru the lens (not the viewfinder) the hole doesn't seem very round {circular} in shape. May I know is it normal.
catchlights Moderator Staff member Sep 27, 2004 21,843 46 48 Punggol, Singapore www.foto-u.com Mar 21, 2015 #2 You are looking at the aperture diaphragm, if it is a bit lopsided, is normal.