Thanks for sharing. I had a noise from the focus ring in manual or auto. Took it apart and found the sticker the indicates focus level was peeling off and hitting the ribbon for stabilizer. Never would have tried it without this video! Back together and all better. Thanks again!
The 100mm F2.8 macro has the same problem & mechanism. Replacing the motor spacer alone didn't work. The roller bearings & all the races had to be cleaned & regreased before it showed signs of life, for the moment. Rotating the motor spacer to fresher parts also helped. Pity that all the EF lenses are falling apart, just as they're being phased out.
I recently had to replace a few screws in my 135 mm f2 L ,the screws that hold the rear element in place had snapped in half. I took it apart fine, and got everything back together but now my auto focus just ping-pongs from in and out of focus and won’t actually confirm on the subject.
For the screws to snap in half, there was probably impact involved. The "hunting" back and forth indicates a loose or torn flex circuit, or the rear lens is not concentric with other elements. Check the flexes first.
I have some wobble in the front barrel with loose screws. It is the section right after the distance meter (not the easier to fix most front area.) At 7:47 in the video are those the screws that likely would need to be tightened for my wobble to go away? Thanks for any help.
Yes, that's frequently a problem with either loose screws (if you're lucky) or a broken cast aluminum subchassis - the shiny internal barrel. If it hasn't been dropped it's probably loose screws. Good Luck!
The "slip clutch" (5:20) has to be right before the AF can work. Aside from manual focus, if AF isn't working, the armature (5:45) might have to be polished with 2000 grit sandpaper. There's a good chance that a new felt bed will not only fix the manual focus but also the AF. Good luck!
I have a 17-55 2.8. The autofocus works okay but the manual slips, sometimes moves other times you spin & spin. Any advice would be appreciated. Thanks
Same design as 70 -200 once you get to the USM motor ( 5:00 ) so the same technique should work. Be careful to note the orientation of any "eccentric" collars you might have to remove to get to this point and reinstall them in the same orientation to avoid focus errors.
@@ghccrtube5007 Oh, that's interesting. I did a research 'cause of slipping focus at my 70-200 f/4.0 IS, but I didn't find anything. Would you please post a link? Thanks a lot.
Parts are no longer available from Canon for this version, but you can sometimes find them on Ebay or China's Aliexpress. Depending on which flex you need it could be as little as $2. I can identify the part name for you if you want to send pics to dcntamcn@aol.com
bro, thank you. your tutorial is working for my slipping focus ring. BTW do you ever have any issue for 70-200 inside parts shaking (maybeimage stabilizer) do you know how to fix it? now my image stabilizer is shaking.
Thank you for commenting. Good to know you got it working. The rattle, like you say, is probably the image stabilizer lens. Sometimes if the lens is removed from the camera before turning the camera off, the IS doesn't have time to move the IS lens to the storage position so it floats loose. If the IS isn't damaged, putting it on the camera then turning the camera off will lock-down the IS lens. If the IS is damaged it's usually one of four posts surrounding the IS lens has broken. It can be super glued into position if you're careful.
Thanks. I got the same problem with the same lens. Can the replacement ring be ordered from Canon or some other place? I don't have a spare lens that i can take the ring off.
Sorry, parts aren't available for this version in the US, but might be found elsewhere or in a "parts only" lens on Ebay. The felt washer wasn't available separate from the complete AF unit, but can be cut from a thin piece of felt or even shirt cardboard 1mm-1.5mm thick.
This is the exact problem I'm having with my mkiii. I brought it second hand and didn't notice it till later. is the focus ring supposed to stop dead or still rotate once it reaches minimum or infinity?
I don't think you have a problem. The manual focus ring has a slip clutch mechanism so that the ring slips when you reach either extent. The problem described in this video is when you rotate the manual focus ring but the "distance scale" stops or intermittently pauses before continuing - or doesn't turn the scale at all.
@@ghccrtube5007 Cool. I've been looking at a few other teardown videos and it looks like the mki is a fair bit different from the mkii and mkiii, especially with the rear group and IS unit having decentering shims. Have you worked on latter two models?
@@JehuMcSpooran Yes, we've repaired dozens of the 70-200mm lenses but collimation is well beyond this video and is time consuming or requires expensive test equipment. Canon no longer provides parts for this version lens so the video was done so the average DIYer can revive it.
Can the bayonet ring be tighten down to increase the tension on the existing gasket or does a new gasket need to be added on top of the old one, or replace the old one all together?
The bayonet ring rides in 3 sloping notches to provide a tiny bit of adjustment. Without test equipment the only way is trial and error. Turn the bayonet ring completely clockwise and test if manual focus slips you'll have to replace the gasket. Less is better.
![Canon RF 70-200mm f/2.8L IS USM | best telephoto lens ever? | Canon EOS R [english | 4K]](/img/n.gif)
Thank you for sharing
I did it just by adding a rubber band and squeeze it in to lock the banjo ring a little tighter, it work very well now.
Good tip!
Thanks for sharing. I had a noise from the focus ring in manual or auto. Took it apart and found the sticker the indicates focus level was peeling off and hitting the ribbon for stabilizer. Never would have tried it without this video! Back together and all better. Thanks again!
Good to know! That's a good lens to hold onto
Gasket material from auto parts stores is just about right as well. Good time to check for foreign material in the gears as well
The 100mm F2.8 macro has the same problem & mechanism. Replacing the motor spacer alone didn't work. The roller bearings & all the races had to be cleaned & regreased before it showed signs of life, for the moment. Rotating the motor spacer to fresher parts also helped. Pity that all the EF lenses are falling apart, just as they're being phased out.
I recently had to replace a few screws in my 135 mm f2 L ,the screws that hold the rear element in place had snapped in half.
I took it apart fine, and got everything back together but now my auto focus just ping-pongs from in and out of focus and won’t actually confirm on the subject.
For the screws to snap in half, there was probably impact involved. The "hunting" back and forth indicates a loose or torn flex circuit, or the rear lens is not concentric with other elements. Check the flexes first.
I have some wobble in the front barrel with loose screws. It is the section right after the distance meter (not the easier to fix most front area.) At 7:47 in the video are those the screws that likely would need to be tightened for my wobble to go away? Thanks for any help.
Yes, that's frequently a problem with either loose screws (if you're lucky) or a broken cast aluminum subchassis - the shiny internal barrel. If it hasn't been dropped it's probably loose screws. Good Luck!
So there is no audio so I played some dramatic music and watching this was so intense.
Dose somebody know if it works the same with the EF 100 mm F2.8 L lens? Or even found something dedicatet for this lense with the same problem?
Thank you very much for your detailed video! I think I have the same issue. It doesn’t work in AF mode either. Is it expected/the same issue?
The "slip clutch" (5:20) has to be right before the AF can work. Aside from manual focus, if AF isn't working, the armature (5:45) might have to be polished with 2000 grit sandpaper. There's a good chance that a new felt bed will not only fix the manual focus but also the AF. Good luck!
I have a 17-55 2.8. The autofocus works okay but the manual slips, sometimes moves other times you spin & spin.
Any advice would be appreciated.
Thanks
Same design as 70 -200 once you get to the USM motor ( 5:00 ) so the same technique should work. Be careful to note the orientation of any "eccentric" collars you might have to remove to get to this point and reinstall them in the same orientation to avoid focus errors.
@@ghccrtube5007 Thanks for the reply & advice!
If 70-200 F/4L IS same it can add ribbon or ?
The F/4 has a different design and a simpler solution to the slipping focus ring, which can be found on YT from others.
@@ghccrtube5007 Oh, that's interesting. I did a research 'cause of slipping focus at my 70-200 f/4.0 IS, but I didn't find anything. Would you please post a link? Thanks a lot.
@@cw7243 Here you go - th-cam.com/video/1Ug6QdsmSnA/w-d-xo.html
Thanks @ghccrtube5007. I discovered this video already, but I want to use the AF function. So it doesn't help a lot. But thanks anyway.
one of the ribbons got messed up when I was putting the lens back together. Now it won't auto-focus. It possible to find a replacement ribbon?
Parts are no longer available from Canon for this version, but you can sometimes find them on Ebay or China's Aliexpress. Depending on which flex you need it could be as little as $2. I can identify the part name for you if you want to send pics to dcntamcn@aol.com
bro, thank you. your tutorial is working for my slipping focus ring. BTW do you ever have any issue for 70-200 inside parts shaking (maybeimage stabilizer) do you know how to fix it? now my image stabilizer is shaking.
Thank you for commenting. Good to know you got it working. The rattle, like you say, is probably the image stabilizer lens. Sometimes if the lens is removed from the camera before turning the camera off, the IS doesn't have time to move the IS lens to the storage position so it floats loose. If the IS isn't damaged, putting it on the camera then turning the camera off will lock-down the IS lens. If the IS is damaged it's usually one of four posts surrounding the IS lens has broken. It can be super glued into position if you're careful.
Thanks. I got the same problem with the same lens. Can the replacement ring be ordered from Canon or some other place? I don't have a spare lens that i can take the ring off.
Sorry, parts aren't available for this version in the US, but might be found elsewhere or in a "parts only" lens on Ebay. The felt washer wasn't available separate from the complete AF unit, but can be cut from a thin piece of felt or even shirt cardboard 1mm-1.5mm thick.
@@crytubecam No parts here in Europe also. I'll have to cut it. Thanks :D
This is the exact problem I'm having with my mkiii. I brought it second hand and didn't notice it till later. is the focus ring supposed to stop dead or still rotate once it reaches minimum or infinity?
I don't think you have a problem. The manual focus ring has a slip clutch mechanism so that the ring slips when you reach either extent. The problem described in this video is when you rotate the manual focus ring but the "distance scale" stops or intermittently pauses before continuing - or doesn't turn the scale at all.
@@ghccrtube5007 I do have the problem you described. I can't do any manual fine focusing with the focus ring.
@@JehuMcSpooran This is the fix you need
@@ghccrtube5007 Cool. I've been looking at a few other teardown videos and it looks like the mki is a fair bit different from the mkii and mkiii, especially with the rear group and IS unit having decentering shims. Have you worked on latter two models?
@@JehuMcSpooran Yes, we've repaired dozens of the 70-200mm lenses but collimation is well beyond this video and is time consuming or requires expensive test equipment. Canon no longer provides parts for this version lens so the video was done so the average DIYer can revive it.
Hello. I'm having trouble with my 70-200 2.8 is. the diaphragm has closed and now it no longer opens. What can you be. What's your e-mail?
If the lens hasn't been dropped, the problem is probably with the aperture flex available on Ebay.
Can the bayonet ring be tighten down to increase the tension on the existing gasket or does a new gasket need to be added on top of the old one, or replace the old one all together?
The bayonet ring rides in 3 sloping notches to provide a tiny bit of adjustment. Without test equipment the only way is trial and error. Turn the bayonet ring completely clockwise and test if manual focus slips you'll have to replace the gasket. Less is better.
good
It's like watching brain surgery.
;)