I modified a J-3 for close-focus over the Summer, used it mostly with the Bessa R2 and M3, which is also modified for 0.7m focus.
The thread on the close-focus mod is here:
http://ziforums.com/showthread.php?t=281
Involves removing the screw that serves as the close-focus and infinity-focus stops, and relies on using the guide pins to perform the action. The threads of the mount must also be filed down to allow the RF follower of the camera to keep up with the cam of the lens.
I expected it to work on the M-Mount cameras, and was pleasantly surprised when the Canon P worked with the lens all the way too its new close-focus, ~0.8m or so.
at F2, ~0.8m
F1.5, ~0.8m
at F4:
And it does focus at "normal distances", out to infinity and beyond. Helps with the Sonnar focus shift.
The thread on the close-focus mod is here:
http://ziforums.com/showthread.php?t=281
Involves removing the screw that serves as the close-focus and infinity-focus stops, and relies on using the guide pins to perform the action. The threads of the mount must also be filed down to allow the RF follower of the camera to keep up with the cam of the lens.
I expected it to work on the M-Mount cameras, and was pleasantly surprised when the Canon P worked with the lens all the way too its new close-focus, ~0.8m or so.
at F2, ~0.8m
F1.5, ~0.8m
at F4:
And it does focus at "normal distances", out to infinity and beyond. Helps with the Sonnar focus shift.