Broken Canon 85mm f1.9 - help

[blue4130]

So I had this lens sitting in my bag one day while I was out and about. I don't recall bumping or dropping my bag extra hard, but when I go home and pulled out the lens, some of the aperture blades had slipped out of their track.

I am hoping that if I can get into the optical block, I can gently maneuver them back into the grooves. Does anyone know why this will not work?

Next, is there a way to take the front lens element out to attack the problem from the front? I tried taking off the front retaining ring, but didn't have any luck getting the element out by lightly thumping it on my hand. Would a suction cup work? Am I missing a step? A lock screw or something?

Any help is appreciated.

 

[jonmanjiro]

Your aperture blades most likely popped out of position because of the the oil on them. Old oil causes drag on the blades when you change the aperture, and if you change it too quickly... pop. I had the exact same problem with a Nikkor-P 8.5cm f2 lens. You're going to need to remove all the blades, then clean and reinstall them. The entire front optical group (front center in the photo below) should unscrew as a single piece giving you direct access to the aperture blades which should be held in place with a circlip and positioning ring. You just need to get a good enough grip on the front ring to be able to unscrew the front optical group.

https://www.flickr.com/photos/62702868@N07/7213283580/

 

[blue4130]

Jon, You are the man. Ill give this a shot this weekend.