Canon EF 50mm F1.4 Disassembly Procedure


rummer

New Member
Feb 8, 2011
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Hello, I have the same problem. One way autofocus. Holder is OK. HELP, please !!!:cry:
 

the adz7d

New Member
Feb 19, 2012
4
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Before i read your forum i already tried to disassemble my lens(same lens).
But only until the the focus ring the same as your procedure. I stopped and put them back because i dont know if i can remove the front element glass. I want to open it because i can see a 1 small dust at the center of front glass and it really make me feel sad:(. Do you think that if i remove the inner part(same you last post picture), i can now remove the small dust inside the front element? Thank you.
 

the adz7d

New Member
Feb 19, 2012
4
0
0
Before i read your forum i already tried to disassemble my lens(same lens).
But only until the the focus ring the same as your procedure. I stopped and put them back because i dont know if i can remove the front element glass. I want to open it because i can see a 1 small dust at the center of front glass and it really make me feel sad:(. Do you think that if i remove the inner part(same you last post picture), i can now remove the small dust inside the front element? Thank you.
 

the adz7d

New Member
Feb 19, 2012
4
0
0
Before i read your forum i already tried to disassemble my lens(same lens).
But only until the the focus ring the same as your procedure. I stopped and put them back because i dont know if i can remove the front element glass. I want to open it because i can see a 1 small dust at the center of front glass and it really make me feel sad:(. Do you think that if i remove the inner part(same you last post picture), i can now remove the small dust inside the front element? Thank you.
 

fatigue

Senior Member
Sep 26, 2005
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Blk138 Bedok North Ave3
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Before i read your forum i already tried to disassemble my lens(same lens).
But only until the the focus ring the same as your procedure. I stopped and put them back because i dont know if i can remove the front element glass. I want to open it because i can see a 1 small dust at the center of front glass and it really make me feel sad:(. Do you think that if i remove the inner part(same you last post picture), i can now remove the small dust inside the front element? Thank you.
This post is not meant to teach how to remove dust. Just ignore the dust.
Even my own lens got plenty of dust.
But if you really bothered by dust, once you reached step 9 (the last photo in page 1) You will notice a small gap on the side that sepates the front and rear optics. This is Where the aperture is located. Just use a blower to blow the dust away.
 

the adz7d

New Member
Feb 19, 2012
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Thanks, I really appreciate it.
Sorry for the double post. I thought I did'nt make the 1st one.
 

sitizenx

New Member
May 18, 2012
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I got stuck at this screw.



The screw won't budge. It had some gunk on it (glue?). I chipped it all off and even used a q-tip with acetone to gently get all the visible blue gunk off. It still won't budge. Any thoughts?
 

Last edited:

Philg31

New Member
Jun 22, 2009
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Australia.
Thank you for the detailed instructions on how to pull the 50 apart.
I have just finished cleaning one and repairing one that was dropped.

cheers

Phil
 

fatigue

Senior Member
Sep 26, 2005
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I got stuck at this screw.



The screw won't budge. It had some gunk on it (glue?). I chipped it all off and even used a q-tip with acetone to gently get all the visible blue gunk off. It still won't budge. Any thoughts?
Oops! I didn't notice this post. Just add a few drops of oil and let it soak overnight. A good screwdriver is the trick to get the job done

here's another link for Canon 50/1.4
http://www.clubsnap.com/forums/canon/919440-fix-dropped-50mm-f1-4-ef-lens.html
 

Jul 12, 2013
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0
Thank you for this guide! I made a video-guide out of it:
---->http://www.youtube.com/watch?v=ED0DQpVnTuM&feature=youtu.be<----

However, my problem wasn't fixed by this. My problem is that the lens will focus just fine from infinity to close, but won't focus a millimeter from close to infinity.

Do I need a new motor?
 

fatigue

Senior Member
Sep 26, 2005
2,930
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Blk138 Bedok North Ave3
forums.clubsnap.org
Thank you for this guide! I made a video-guide out of it:
---->http://www.youtube.com/watch?v=ED0DQpVnTuM&feature=youtu.be<----

However, my problem wasn't fixed by this. My problem is that the lens will focus just fine from infinity to close, but won't focus a millimeter from close to infinity.

Do I need a new motor?
Confirm the problem by testing at manual focus.
If the same problem, then barrel is not in perfect shape yet
 

Last edited:
Jul 12, 2013
2
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0
Confirm the problem by testing at manual focus.
If the same problem, then barrel is not in perfect shape yet
Sorry, forgot to mention that part. In manual focus, everything works fine. I can focus from both near to infinity and vice versa.
 

fatigue

Senior Member
Sep 26, 2005
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The barrel has to be checked carefully. A small imperfection could mean that the motor is working harder to turn the barrel in the opposite direction. With a half assembled lens, I try to slowly turn the white gear and "feel" the stiffness of focusing in both directions

Yes, there are also cases wherein the problem is caused by faulty motor. The usual symptom is that the focusing does not move at all at AF mode. Lately, I have learned the art or refurbushing USM/SWM including brush motors. So if it's not the barrel, I will check the motor

Hint: When the motor is working hard, it will consume higher electrical current