Z7 Lens and focus problems at DVinfo.net

Keith Forman · June 25th, 2010, 08:31 PM

I have been increasingly unhappy with the focus of my Z7 since I purchased a Z5 last year. The Z7 does not seem to maintain its focus across the entire screen. The right side has particularity bad focus . It also shows the blue fringe on a high contrast Indian test pattern.

I have tried two lenses (manufactured 2.5 years apart). I have carefully done the flange back. Almost the exact same issue.

Any ideas? Attached is a picture of the test pattern.

Keith Forman

Wacharapong Chiowanich · June 26th, 2010, 11:16 AM

Looks to be a mis-alignment of the prism or sensor block which is too far offset to one side of the lens mount axis, causing the vignetting on the right side of the frame. Two lenses with similar results indicates a problem somewhere in the positioning of either the lens mount or the prism/sensor block.

Since this problem points to a manufacturing defect, you'd better send the camera in.

June 25th, 2010, 08:31 PM	#1
Keith Forman Regular Crew Join Date: Mar 2008 Location: Williamstown Mass Posts: 192	Z7 Lens and focus problems I have been increasingly unhappy with the focus of my Z7 since I purchased a Z5 last year. The Z7 does not seem to maintain its focus across the entire screen. The right side has particularity bad focus . It also shows the blue fringe on a high contrast Indian test pattern. I have tried two lenses (manufactured 2.5 years apart). I have carefully done the flange back. Almost the exact same issue. Any ideas? Attached is a picture of the test pattern. Keith Forman Attached Thumbnails __________________ http://www.vimeo.com/keithforman/videos http://www.keithforman.com

June 26th, 2010, 11:16 AM	#2
Wacharapong Chiowanich Major Player Join Date: May 2008 Location: Bangkok, Thailand Posts: 400	Looks to be a mis-alignment of the prism or sensor block which is too far offset to one side of the lens mount axis, causing the vignetting on the right side of the frame. Two lenses with similar results indicates a problem somewhere in the positioning of either the lens mount or the prism/sensor block. Since this problem points to a manufacturing defect, you'd better send the camera in.