Canon 50mm f1.8 LTM Clean-up

[br1078lum]

Got this lens on the Yashica YF, and it was like looking through ground glass.


Canon 50mm f1.8 Cleaning 2 by br1078phot, on Flickr
The outside of the lens is in excellent shape, the focus action is smooth, but the aperture ring is a little stiff to my tastes.  This could just be the way it is, I don't know, but the blades are clean and oil free.

The elements on the other hand are another story.  This appears to be on one of the rear ones, so I'll tackle this from that direction


Canon 50mm f1.8 Cleaning 3 by br1078phot, on Flickr
Took off the first ring using the larger slot spanner.  This lets the focusing mount come off in one piece.


Canon 50mm f1.8 Cleaning 4 by br1078phot, on Flickr
The focusing mount is very hard to put back on the wrong way, due to the large key that fits into a slot on the optical block.  And no springs or ball bearings came flying out either.


Canon 50mm f1.8 Cleaning 5 by br1078phot, on Flickr
The rear element comes out next, using the smaller slot spanner.  It was in good shape, just a bit of cleaning neccessary.


Canon 50mm f1.8 Cleaning 6 by br1078phot, on Flickr
The next element turned out to be the culprit.  It comes out by using a point spanner, and with the canted heads on mine, it was a little tricky making sure I didn't do any damage while fitting it into such a tight space.

I also took off the thin ring you see at the top of the image just in case.  It's not neccessary to do so, but I like to err on the side of caution.


Canon 50mm f1.8 Cleaning 7 by br1078phot, on Flickr
Since the rearward facing side of this element has a surface not unlike the rear element on a Jupiter-12, I took the precaution of mounting it backwards in the optical block as a holder for cleaning.  Whatever was on the element came off mostly with regular old Kodak Lens Cleaning Fluid.  I then cleaned it again with alcohol, and the fluid one more time.  It came clean, but there is some damage to the coating of the element.


Canon 50mm f1.8 Cleaning 8 by br1078phot, on Flickr
The lens reassembled.  Things are much clearer now, and if my p&s digital had the capabilty to manually focus, you could see how sharp the image of the lettering on the pen in the background is.

The camera had a few issues of it's own.  I dealt with them here:
http://www.flickr.com/photos/7699588@N07/sets/72157627788191918/

PF

[CarlosE]

Very good work PF !
I admire greatly your talent for to do this... and with very good results !!!

Congratulations

Carlos

[radiophoto]

Excellent job, Phil.  Nice pics and a good how-to.

[br1078lum]

Thanks guys.  I picked up a few tips along the way while fixing torpedoes for the Navy, and signal equipment for the railroads.  I just have to scale down the experience when working on camera gear.  And older stuff like this is less complicated than what came out after the SLR was born.  Except for anything made by Zeiss.  Theirs is always complex.

PF

[brazile]

Really good to see something like this come good -- very rewarding, isn't it? Thanks for taking us along for the ride.

Robert

[OpenWater]

Phil,
I enjoyed this series.  If I ever find the time, I've got a couple of cameras that need cleaning up.  It is good they don't explode like the torpedoes you used to work on!
Mike

[LarryD]

Last time I took one apart it ended up in the dumpster... You did great.

[Raid Amin]

I wish that I had your talents in taking a lens apart.

Raid

[br1078lum]

Raid, I think I inherited it from my Dad, who was a master machinist.

PF