Fixing a stuck focus ring on a Canon 50mm f1.4 lens


So a few months back disaster struck, I managed to break my 50mm 1.4 lens! Focus completely jammed - couldn't even manually focus. gutted. I took the lens to my local camera shop and they said they would have to send it off to Canon and it could cost up to £180! Ouch.

Having just forked out for xmas, car insurance and about a gazillion other things that wasn't a particularly inviting proposition. So in some what of a bold move I decided to take matters into my own hands.

After a quick web search it became clear that this fault is actually quite a common problem with this particular lens and is caused by an arguably dubious design choice on Canons part.

Disclaimer
What follows is a guide to what I did to fix the problem, I am not a professional repairs person and I am not for one minute saying this is the best way to fix your lens, but it worked for me. This is a delicate procedure that could easily go wrong and if you try this yourself you do it entirely at your own risk. If you are in any doubt, send it to a professional.

Tools
To dismantle the lens you'll need PH0 & PH00 precision screw drivers, also useful will be a scalpel, fine tipped tweezers, lens cloth, some sort of tray to put bits in & a pen and paper. 

In order to fix the actual problem you want a good quality digital calliper and a hammer. Yes that's right you'll be hitting you beloved lens with a hammer. There are other ways to do this and I'm sure there are much more professional, efficient and expensive tools for the job. This is simply how I chose to attack the problem (literally!)











Feeling reckless?
Good, then we shall continue. Clear a large brightly lit area, lay out your tools and place the lens in question on your lens cloth.

As you are working I would highly recommend keeping all the various parts and screws labelled and possibly in separate containers. 

Read this guide through at least once before you begin and make sure you have all the tools needed to hand.

Step 1

Remove the 3 screws around the top of the lens. you can now gently remove the front casing and focus ring by sliding them off the end of the lens. Notice that there is also a small clear plastic ring just underneath the front casing. remove all these parts and put them to one side.


Step 2

Turn the lens upside down and remove the 4 screws marked in red. The silver lens mount is also attached to the body with some tacky resin, take your scalpel and very gently prise the lens mount loose. I say gently because the small part with the gold contact plates is attached to the base plate and the lens body by a contact band, if you damage this connection you will most likely ruin your lens entirely. At best it will no longer be able to communicate with the camera.



Step 3

This is one of the trickiest parts to the procedure. Lift the lens mount on the opposite side to the gold contacts and you will see that the black plastic inner ring is attached to the metal mount with 4 plastic 'hooks'. What you need to do is gently but firmly prise these off the metal mount with a small flat head screw driver. This is particularly difficult because you'll need to use some force but be very careful not to (a) snap the hooks off & (b) damage the contact band attached to both lens and mount.
If you can prise 2 of these hooks open the inner plastic part should come free.



Step 4

Next remove the two screws marked in red, but not the one marked in yellow. You can now remove the metal mount plate.



Step 5

Ok, now we're gonna remove the little panel that holds the AF/MF switch. This is secured in place with a little blob of glue so start by cutting through this with the scalpel. Once done carefully slide the panel up and out. I say carefully because there is a very small switch behind the panel that could be easily damaged (see pics) What you'll want to do is push the panel up a touch and then tilt the bottom of the panel out a touch so that it can clear this switch. Once that's done you can slide off the last bit of outer casing (the bit that says '50mm' on)






Step 6

Now we need to detach the contact band pictured below. Take your tweezers or scalpel and slide the little white braces out in the direction indicated. They should slide out quite easily by about 1-2mm, once done the contact band can easily be removed from the socket.



Step 7

Remove screw and contact plate indicated below

Step 8

Remove the white plastic runner guides, there are 3 and they will all need to come out.


Step 9 

That contact band that we detached in step 6 is also attached to the body with a blob of resin glue, at this point you need to very carefully prise this free. I gently pulled up on it and cut through the resin with my scalpel. Once done you can slide off the main housing as illustrated, threading the contact band through the gap as you go (its attached to the inner lens housing)



Your beloved lens will now look like this... (scary huh?! lol)


Step 10


We're nearly there and you can now see what the actual problem is. Remove both white plastic guides (circled in red) and slide off the guide slot housing. Where the guide slot meets the top of the housing the metal is VERY thin, it would seem that even a small amount of pressure on the front of the lens can cause this to bend out of shape. You can see quite clearly a large bulge at the top of the housing where it should actually be flat.







Step 11

Now all you need to do is bend that housing back into shape! Well, I say all, this is actually quite a tricky job. That guide slot is precision engineered and needs to be exactly the same width all the way along. Which is where your digital callipers come in!

There are quite a few ways of bending the metal back but its vital that you take repeated measurements all the way along the gaps (there's one on each side of the housing) as you are working. your aim is to get those gaps as even as possible all the way along. Even the slightest deviation will cause problems in focusing - most commonly either being sluggish or getting stuck at certain points.

Before you start bending run the housing under a hot water tap for a few minutes, this will make the metal more pliable and easier to work with.

In theory its possible to take the silver metal bracket off, although mine was so ridiculously tight I could not do this. If you can you could try putting the housing (bulge down) on a hard flat surface and pushing down on it to straiten out the metal.

I resorted to putting a flat piece of metal over the bulge and tapping with a hammer, which actually worked pretty well. you could also try putting the whole thing in a vice. Like I said at the beginning, there are probably precision tools for this sort of thing, but I neither own, nor know anything about such tools.

Finally

Once you're happy with your bending and straitening efforts simply follow the steps in reverse order. If the lens is sluggish or gets stuck at certain focus points do the whole procedure again (it took me 2 attempts)

When you're reassembling, bear a few things in mind ~ make sure you don't over tighten the white plastic guides (steps 10 & 8) if they are too tight it will make focusing sluggish. Also if the camera has trouble communicating with the lens try tightening the four screws in step 2 and/or cleaning the gold contact points.

Good luck!

Resources

There are a number of articles and discussions about this procedure that I used to learn how to do this. My aim with this post was to compile the best of this information in one place, hope you find it useful. Here's a number of other places that this is being discussed...

http://www.clubsnap.com/forums/canon/919440-fix-dropped-50mm-f1-4-ef-lens.html
http://www.fotomozaic.ro/artikel.php?idstory=225&s=1
http://www.clubsnap.com/forums/canon/475106-canon-ef-50mm-f1-4-disassembly-procedure.html








41 comments:

  1. Thank you for this walk-through. It was step-by-step and just what I needed. Thanks for being the brave one so that other might follow your path.

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  2. Thank you, sir! This just saved my lens and me a few euros in the process. Crystal clear directions and great accompanying photos to go along with them - exactly what I needed for such a daunting task. Very much appreciated.

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  3. Thank you a lot! I have fixed my lens today. It took me about 2 hours. If wasn't your instructions I would certainly send it to the servise and pay a lot of money and waiting a month at least. If you ever come to Croatia, text me and ask for any kind of help you need. I have a real estate agency and presenting my propertis with virtual tours 360° made by myself. Take a look and contact me if you like: www.8realestate.eu

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  4. YOU ARE THE BEST!!! Thanks so much... just fixed my lens :)

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  5. Thank you for this. worked a treat. :D

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  6. Now I get a "00" Error from my camera...I think I damaged something :(

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  7. Thank you so much for this!! Helped so much! I did notice a major design flaw. The third plastic guide (located on right side-in straight feed) slows focusing and I believe has burned out many motors in these types of lens. Removed and works perfectly! No more stuck focus ring.

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  8. Clear description. Very helpful. I fixed my lens in 2 hours. Thanks a lot!

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  9. ugh- I just dropped my Canon EOS 5D with the 17-40m attached and it broke clear off the ring!!! Ideas please-? is there any hope in saving it? Anyone know where to send it? Is there anyone in NYC that can look at it? I can't even tell if maybe something is wrong with the body or even imperfection now in lens-glass.

    Thanks for any help at all

    :(

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  10. I successfully fixed my lens following your guide. Thank you! In my case it was the metal track on the oppsite side that was bent out of shape.

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  11. Isn't that ring made of plastic? I dont think this is metal.

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  12. Thank you so much for this tutorial, my lens was driving me insane and canon was going to charge me a lot, it was hard to dissasemble but I did it , now it works like if it was new!

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  13. Dude, you are a genius. I can't believe how easy that was. Granted, I had the right screwdriver and exacto knife laying around already, but still. Hardest part to me was getting the flat cable reconnected. Got a hard fault (no communication) when I first assembled the lens, but knew what the problem was, went back and reconnected the flat cable - got better contact - and all is well. Love this lens. SO SHARP. I didn't want to part with it. Now I don't have to. Thanks!

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  14. This is an absolutely fantastic money saving post. Well done!
    Let me add my two cents on what seems to have worked for me. I have dissembled and assembled my lens twice, and the second time, the first time with no apparent improvement. The second time, I noticed that loosening the 4 plastic runners you mentioned in step 8 made the focusing ring looser. These guides are accessible after step 1! I suggest that those of us with focusing ring problems try loosening the runner screws to see if solves the problem before going through the other, more dangerous steps. Secondly, in step 10, for me, my slot and housing looked EXACTLY like the one photographed. I suspected that was a design thing and not something I did by dropping the lens. I actually do not recall dropping the lens. Because of this, and the fact that is plastic, I didn't try and change the shape of the housing

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  15. You should put your thorough work on iFixit.com!

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  16. I followed the guide step-by-step and now the lens works perfectly.

    However I didn't really use the caliber, it was easy to see by eye when the housing was in place.

    The hardest part was to remove all screws without damaging the kernels. :)

    Thanks a bunch!

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  17. Unbelievable! in one hour i fixed my beloved lens, thanks to your clear description.
    now my lens works perfectly.
    thanks!!!

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  18. Thanks for the detailed autopsy. Didn't know the lens was that fragile. Although it did hit my daughter's head with a bit of a force when I tried to grab her from tripping over. The girl didn't require as much effort to function properly afterwards.

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  19. One word of caution to DIYers in step three I would recommend to not remove the inner black plastic ring. That piece of plastic is a know problem with both the 1.4 and 1.8 50mm lenses. What happens is immediately or over time that black plastic ring (dust cover) can loosen and if it does it will not allow you to release the lens from the camera. See these links:

    http://photo.stackexchange.com/questions/53207/50mm-stuck-on-the-body

    The alternative is that if you must remove the black ring, just don't put it back on when you reassemble the camera. It's not necessary, and can totally screw up your lens & camera body if it fails.

    Other than that this post was very helpful, and left me with a feeling of accomplishment....

    Thanks

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  20. THANK YOU SO MUCH for this tutorial. I recently damaged the focusing ring of my fixed 50 and was a day away from replacing it/sending it away to be fixed. I came across your tutorial last night and attempted it this morning with so many doubts running through my head before and during the procedure. Again, I appreciate you taking time out of your day to take these photos and write out these detailed directions. You saved my bank account.

    Thank you again a million times over.

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  21. I followed Bushman's advice in his comment below the article, and simply loosened the screws for the 4 white runners (visible after step 1 of the guide). Then reassembled and my lens focused perfectly. May be worth trying this before taking the whole thing apart as it took me all of about 3 minutes to fix! Good luck and thanks so much for the guide.

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  22. I was very hesitant to undertake this given the many ways this could go wrong. But given the cost of sending this back to Canon I decided to go ahead I followed this and an excellent youtube video by Christofer Cederberg. I am pretty handy and has the tools except for a PH000/PH000 screwdriver. So, that was about $5.

    Everything went fairly well. The ribbon cables were my only slight challenge. Initially I disconnected the wrong one. There are 3, so just be careful. The cable is glued to the inside of the barrel, so I had to use a bit of force to dislodge it. I couldn't find an easy way to get a knife inside to cut the glue.

    When you're stripped down to the offending part it is not very obvious that there is a problem. It looks like a solid plastic piece that is fine. Once I put mine on a flat hard surface I could notice the slight wobble. By applying pressure from the top I worked the wobble out.

    Everything went back together fairly well. The clip that tightens the ribbon cable had popped off, so I had to get that back on. Was a bit finicky but got it on. Everything else goes together fairly well.

    When all said and done, put it back on the camera and crossed my fingers. I had full range of focus so that fixed my problem. But, in autofocus it kept hunting. Argh! Figured it had to be in one of the electrical connections so decided to take it apart again, at least to the 1/2 way point where the connectors are.

    But, the lens was now stuck on my camera and wouldn't come off. I wish I had read all of the comments on this thread and the issues with the black ring. I used a bit of force, against by better judgment, and it did come off.

    I then took it apart again to the 1/2 way point. The first ribbon cable that I had accidentally disconnected was now only partially locked into the connector. Fixed that up, reassembled everything, and all good to to go now!!!

    Many thanks to the author of this post and the many other enthusiasts out there who have posted videos, comments, etc. The money I saved paid for my expensive Sirui monopod and a few other accessories!

    ReplyDelete
  23. I was very hesitant to undertake this given the many ways this could go wrong. But given the cost of sending this back to Canon I decided to go ahead I followed this and an excellent youtube video by Christofer Cederberg. I am pretty handy and has the tools except for a PH000/PH000 screwdriver. So, that was about $5.

    Everything went fairly well. The ribbon cables were my only slight challenge. Initially I disconnected the wrong one. There are 3, so just be careful. The cable is glued to the inside of the barrel, so I had to use a bit of force to dislodge it. I couldn't find an easy way to get a knife inside to cut the glue.

    When you're stripped down to the offending part it is not very obvious that there is a problem. It looks like a solid plastic piece that is fine. Once I put mine on a flat hard surface I could notice the slight wobble. By applying pressure from the top I worked the wobble out.

    Everything went back together fairly well. The clip that tightens the ribbon cable had popped off, so I had to get that back on. Was a bit finicky but got it on. Everything else goes together fairly well.

    When all said and done, put it back on the camera and crossed my fingers. I had full range of focus so that fixed my problem. But, in autofocus it kept hunting. Argh! Figured it had to be in one of the electrical connections so decided to take it apart again, at least to the 1/2 way point where the connectors are.

    But, the lens was now stuck on my camera and wouldn't come off. I wish I had read all of the comments on this thread and the issues with the black ring. I used a bit of force, against by better judgment, and it did come off.

    I then took it apart again to the 1/2 way point. The first ribbon cable that I had accidentally disconnected was now only partially locked into the connector. Fixed that up, reassembled everything, and all good to to go now!!!

    Many thanks to the author of this post and the many other enthusiasts out there who have posted videos, comments, etc. The money I saved paid for my expensive Sirui monopod and a few other accessories!

    ReplyDelete
  24. I'm not quite sure what is the problem with mine. My focus ring spins normally but the focus distance goes from infinite to 1.5 normally and then it stops, even if I can continue spinning the focus ring.
    The same happens with autofocus, I can focus just very far away.
    Is this the problem that you guys had? It would be nice to know before getting into this adventure
    Thanks

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  26. Hi guys, I'm just wondering if I have the same issue that you have.

    I can spin my focus ring normally, and the distance focus works normally as well from infinite to 1.5 and then it stops while the focus ring keeps spinning (manually)

    Same with the autofocus, I can focus just on far away stuff.

    Do you guys have the same issue, do you think that this guide is the right solution for me?

    Thanks

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  27. This comment has been removed by the author.

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  28. This comment has been removed by the author.

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  29. This comment has been removed by the author.

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  30. I can only get 1 of the 3 outer screws out...this is not going so well!!! Any suggestions on how to get them out??

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  31. I had to pull one through, i.e use force. If the lens is not working anyway it's no loss. The lens only needs two screws to function. Probably you are using the wrong size screwdriver, if you destroy the head of the screw you'll just have to pull it.

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  32. Last January, we had this festival and a colleague has this 50mm 1.4 and has the same issue. While shooting, his lens got locked aperture. What he did was he gave me the lens and attached to my unit, then set the lens from AF to Manual, changed the Aperture from High, then shoot, then set again to Low and shoot again. The lens got fixed and he used it again. An alternative before manually fixing it.

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  33. This was exactly the same issue I had with my camera, after I had dropped it.

    Thanks so much for this tutorial!

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  34. thank you very much, very easy and successful

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  35. This tutorial saved my lens! This lens was sitting on my camera when one of my tripod legs gave out, a joint was not tightened down enough, and smash, landed right on this lens. I took it to a shop, they said it would cost just as much to repair it as it would to fix it. Looking at replacing it completely, I decided to take it apart in a last ditch attempt. I found this guide. A god send.

    The next problem I faced, my barrel was bent and the grooves on the tube were broken off. About half of the little gear grooves had fully broken off. So I found a replacement part on Ebay for less than $20, and patiently waited.

    The replacement piece came today and my lens is back to normal function. I managed to break off the tiny auto/manual switch, but that does not bother me considering I loathe auto-focus. Of course the first time I put it back together I had the switch on auto, but now it's all put back together and working like new with only a few bruises.

    So THANK YOU for saving my lens and my wallet!

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  36. Thank you! Like the others, this tutorial saved my lens! Now I just wish I had seen it before I let my 85mm with the same issue go!

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  37. Same thing happened to me today. The ring was spinning in the manual mode, but focus wasn't moving. I decided to follow the Bushman's advice and just loosen the screws on the white plates visible after step 1 - it worked like a charm! THANK YOU!!!

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  38. Followed your advice and now the lens works, but it's stuck to my camera body... :(
    Can't seem to take it off

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  39. Got a good read, losened the 4 white guides a little :) http://www.rgphoto.nl

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  40. its the center lenses that fell out so takin it all apart wont help me put it back together :(

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  41. Thanks dude, lens is back in shape!

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