Repairing a Sigma 70-210 f/2.8
Printed From: Dyxum.com
Category: Equipment forums
Forum Name: A-mount lenses
Forum Description: For A-mount lens discussions
URL: https://www.dyxum.com/dforum/forum_posts.asp?TID=8708
Printed Date: 16 February 2025 at 09:10
Topic: Repairing a Sigma 70-210 f/2.8
Posted By: Gubbe
Subject: Repairing a Sigma 70-210 f/2.8
Date Posted: 27 November 2006 at 14:38
Well, 'repairing' may be too strong a word, but the lens is usable and I only ended up with one extra screw and a piece of extra glass... ;)
I bought a Sigma 70-210 f/2.8 APO from a Dyxumer for about a hundred EUR. It had trouble with focusing whereby the focus mechanism would jam and sound very rough. In essence, AF was completely useless and even MF was barely usable.
I opened it up a long way from the rear (mount) side, removed the mount, the rear barrel, the rear group with the diaphragm and electronics, some AF gearing and spent a whole lot of time removing the Zoom ring mechanism, but still couldn't gain access to the front of the lens.
I didn't see any obvious methods of opening the front besides a filter ring -type thin ring that held the front elements in place. When I tried to remove that ring, it got horribly stuck and I had to cut it with a dremel to get it off (did it quite nicely actually). After doing that I noticed to my humiliation that it wasn't even supposed to be possible to remove it that way because the threads it was on were recessed beyond the filter threads slightly. Yet, I still couldn't get the lens open so it was left collecting dust.
Then one evening, just a few days ago, I was getting ready to go to sleep and found a neat screwdriver that would let me try and open some screws in a very difficult to reach place inside the lens. That turned out to be a false hope since the screws were glued tight. I took the lens in my hand and really started to ponder how the outer shell could be removed. I twisted and turned everything that I had already twisted and turned a dozen times before and suddenly a threaded ring came loose near the focusing ring and it was all obvious. The front barrel came off and I could access the focus threads and clean them thoroughly, applying just a dab of grease in the process. After cleaning the front elements well (they had got dirty during all this) I started to put the lens back together. This was at about 3 AM so I was just a wee bit tired. I dropped the lower front element in the lens barrel where it was supposed to be dropped, but did so carelessly and to my horror a piece of glass chipped off the edge of the element! I assessed the damage and came to the conclusion that although that wasn't a Good Thing(TM), it was insignificant enough to not cause major problems with the light transmission. The pics you'll see will show what the chip looks like.
Well, I finally got the lens reassembled and went to bed. The next day it seemed to work quite ok before the AF motor suddenly went "Whrrrrrrrr!" The AF motor axle had decoupled from the focusing mechanism somehow and I could hear a rattle inside the lens. At this point I was more amused than annoyed so I opened the back of the lens again to find that one of the gears from the AF gearing had popped off. The gear, although it stayed quite nicely in its place at rest, became twisted when torque was applied because its axis was loose from the mounting plate. I managed to reattach it with a spike and a hammer and now it should stay in place quite fine. In retrospect, this loose gear was probably the main reason that the AF jammed, although it had probably become loose because of the rough focusing threads.
Although a lot less clunky than prior to the gear popping, the focus still seemed a bit heavy so I opened it up from the front again and wiped off all the grease from the bottom of the threads, removing a lot of minute metal dust in the process. I tried a different grease, but ultimately wiped that off too. I left it with a very thin layer of residue grease and now it seems to move relatively smoothly - well enough for me to be happy with it, although the focus mechanism was probably a lot smoother when it was new. During all this I managed to re-smudge the front elements so I cleaned them again, but I took short cuts and some grease was left on the edges. I'll probably take it open once more and clean those off too. There are probably some small scratches on the glass as well from the handling. I managed to light it nicely to show and exaggarate all the ugliness in one of the pictures I'll link to later.
The autofocus mechanism works now and doesn't make me fear of overheating the focus motor, but it seems to do strong hunting. In other words, it overshoots, then compensates and overshoots in the other direction, going back and forth across the proper focus distance. I'm hoping that cleaning the front elements will reduce this behaviour. I will also try blocking light from entering the lens through the chipped part, just in case that causes havoc with the focusing.
I'll post some pictures at the address below. See the 'Large' directory for full res shots.
http://imgur.com/a/iG6L5 - Pictures!
I'll probably keep this baby, but if someone wants to buy it, make me an offer.
Thanks for reading all the way through! Feel free to ask questions.
------------- Arto Rantala
gubbe@sci.fi
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Replies:
Posted By: Gubbe
Date Posted: 27 November 2006 at 15:04
Waaah! I just broke off that same little gear again! ¤@#&§*!
------------- Arto Rantala
gubbe@sci.fi
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Posted By: Bob J
Date Posted: 27 November 2006 at 15:09
Ahh, the saga of dis-assembley without instructions... very often the removal of the broad rubber focus/zoom bands reveals a way in. I don't think the chip will do much damage to contrast - the grease is probably much more of a problem. Your story highlights one of the things I've found from taking lenses apart - the focusing linkages on some of the third-party lenses (chiefly cheap Tokinas in my case) can leave a little to be desired. Even the cheap Minolta lenses (such as the 35-80 with the integrated lens cover) are impressively built inside.... That reminds me, I've still to find a way into that 28-105 xi zoom with the sticky aperture...
Bob
------------- RBJ ~ http://tinyurl.com/h7uhozk - Moderation on Dyxum
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Posted By: Frans
Date Posted: 27 November 2006 at 15:11
Maybe this teaches us that fixing lenses with a hammer doesn't work that well?
Not sure how the complete story was meant but reading it make me chuckle here and there.
------------- Dynax 7D - VC-7D - AF 28 F/2.8 - AF 50 F/1.7 - AF 135 F/2.8 - 3600HS (D)
AF 17-35 F/2.8-4 (D) - AF 28-75 F/2.8 (D) - AF 35-70 F/4 - Sigma 170-500 F/5-6.3 APO
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Posted By: Gubbe
Date Posted: 27 November 2006 at 16:57
Who cares if fixing lenses with a hammer doesn't work that well? It's fun!
The gear axle is actually made of very soft metal and its attached into the plate by expansion of the end, done by striking a pin into the dimple at the end of the axle using a hammer. Unfortunately I've mangled the axle by using "suboptimal" equipment and decided to try different methods.
The epoxy is currently curing on the gear axle. I'm hoping that will hold it in place. If it doesn't then this thing will probably become a manual focus lens.
I'm wondering if that loose gear, assuming it came loose right away back when I last assembled the thing, could be the culprit in the AF hunting.
I'll have to test it again after the epoxy cures.
------------- Arto Rantala
gubbe@sci.fi
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Posted By: paulobro
Date Posted: 27 November 2006 at 17:46
Mmmm...
Somehow I don't see Sigma frenzied to hire your services for their shop.
Nor a crowded, way overshot ebay auction...
But then, I'm oftenly wrong.
------------- Paulo Brochado
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Posted By: Bob J
Date Posted: 27 November 2006 at 18:01
Any chance you could get a spare bit from another Sigma lens?
Bob
------------- RBJ ~ http://tinyurl.com/h7uhozk - Moderation on Dyxum
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Posted By: CKsam
Date Posted: 27 November 2006 at 18:57
Gubbe wrote:
I'm wondering if that loose gear, assuming it came loose right away back when I last assembled the thing, could be the culprit in the AF hunting.
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I agree that fixing lenses can be a lot of fun! It's hard to completely ruin them if you're careful. I love picking up dodgy broken lenses and getting them working again to (nearly) full capability.
The AF hunting could be due to bent sliding contacts on the circuit board/ROM bit. I had a similar problem when I took a Minolta 28-135 to pieces to fix something different. It's easy to bend the little contacts a bit on the reassembly without realising it. Worth a try, perhaps, but I could be completely wrong.
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Posted By: Gubbe
Date Posted: 27 November 2006 at 19:04
Thanks for the tips! I'm sure I could use a spare, but finding a donor lens might be really difficult.
I'll have to start looking if this epoxy thing fails.
I would investigate CKsam's idea too, but there are no electronics in the focusing part. Only the zoom ring has a cable coming out from it and even then it's only for the focal length data which I understand is of no concern to the AF system. If you think I'm missing something, please inform me.
Just to be on the safe side though, I'll be sure to test that the focal length data is correct by taking shots at different zoom settings and looking at the EXIF info.
------------- Arto Rantala
gubbe@sci.fi
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Posted By: Gubbe
Date Posted: 28 November 2006 at 21:06
CKsam you are a bloody genius!
I took pictures with all focal lengths and the exif data for the focal length from 150mm onwards reads like this:
150mm 160mm 135mm 120mm 120mm 210mm.
I twisted the zoom ring with considerable force for the last pic.
Incidentally, AF works fine up to around 150mm, only hunting beyond that. (Yes, I fixed the gear.)
BobJanes also deserves a big wet kiss straight on the mouth. I removed the rubber on the zoom ring and found a hatch that gives direct access to the slider that shorts out the contacts for the focal length. I just needed to clean the contacts and adjust the brushes a bit and voila! The focal length is now correct in the EXIF and there is no large-scale hunting left whatsoever!
Had I not known to look under the rubber, I would still be disassembling the zoom ring trying to find access to the brushes or spraying contact cleaner everywhere.
Right, about the gear. Like I said, I epoxied the axle and it came out fine. When screwing the plate back in its place I noticed that the gears turn very smoothly until the leftmost screw is fully tightened. I placed a small piece of very thin plastic under the corner of the plate and then tightened the screw and it's now smooth! Yes, the AF and MF are both now much smoother than they were before, I'd say they're almost like new!
Oh right, the epoxy. Although it came out well, I still didn't want to risk it since if the axle popped off again, it would be very difficult to re-attach. So, I cut off a piece of a toothpick, placed a piece of the same plastic on top of the gear as a cover and epoxied the stick so that it supports the top end of the axle. I also did it because I had broken the clip that holds the gear in place. Now the axle is supported from both ends and although the whole thing looks ugly, the axle will never come loose again. EVER.
Now all I need to do is clean the front elements and aside from the chip in the glass, this thing will be good as new!
------------- Arto Rantala
gubbe@sci.fi
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Posted By: CKsam
Date Posted: 29 November 2006 at 10:36
Great news! Now for another project, eh?
Sam.
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Posted By: Gubbe
Date Posted: 29 November 2006 at 11:01
Yes indeed. You've all seen my http://dyxum.com/dforum/forum_posts.asp?TID=8676 - WTB thread and I already have a Sigma macro coming in, should be here any day now.
I'll go clean the front elements now, hopefully for the last time. ;)
------------- Arto Rantala
gubbe@sci.fi
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Posted By: beeton
Date Posted: 27 January 2020 at 01:31
Re 70-210 f2.8 APO,
Gubbe. It's been awhile but thought I would ask. I am trying to deal with a rough focus as well, took the rear off up to the gears but stuck at that point. When looking inside the front, I noticed a plastic ring floating around so something has loosened up. I don't quite understand the front removal procedure. Did you say the front barrel unscrewed (the front element along with it)? This is on tight and I want to be sure before I try it again.
Thanks.
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Posted By: neilt3
Date Posted: 27 January 2020 at 08:57
beeton wrote:
Re 70-210 f2.8 APO,
Gubbe. It's been awhile but thought I would ask. I am trying to deal with a rough focus as well, took the rear off up to the gears but stuck at that point. When looking inside the front, I noticed a plastic ring floating around so something has loosened up. I don't quite understand the front removal procedure. Did you say the front barrel unscrewed (the front element along with it)? This is on tight and I want to be sure before I try it again.
Thanks. |
Gubbe's last visit on Dyxum was December 2016
You might get a response from him if you send a P.M . As long as he still uses the same email address he will get a notification that you have sent a message . Good luck with your lens !
I'm still trying to figure out how to remove and separate to the rear lens group of a Sigma 300mm f/2.8 . Only been about 5 years !!
------------- see my photostream on flickr; https://www.flickr.com/photos/neilt3/sets/ - http://www.flickr.com/photos/neilt3/ C & C welcome.
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Posted By: beeton
Date Posted: 27 January 2020 at 12:55
Rear group.... if I recall other similar lenses, 4 silver screws for mount, 3 small black ones for shroud, 2 slightly large black ones for contacts, rear cell should unscrew. They may have used locktite type products on the threads. Send a picture if you have one.
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Posted By: neilt3
Date Posted: 27 January 2020 at 23:29
beeton wrote:
Rear group.... if I recall other similar lenses, 4 silver screws for mount, 3 small black ones for shroud, 2 slightly large black ones for contacts, rear cell should unscrew. They may have used locktite type products on the threads. Send a picture if you have one. |
I've no pictures to hand , that's if I took any . When I get chance I will dig the lens out and post some to i.d it , as well as stripping some of it down again to have another look at it .
The rear lens group has haze , hopefully just a layer on the innermost parts that will clean up , and not between two cemented pieces .
------------- see my photostream on flickr; https://www.flickr.com/photos/neilt3/sets/ - http://www.flickr.com/photos/neilt3/ C & C welcome.
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Posted By: Osi
Date Posted: 31 March 2020 at 12:29
neilt3 wrote:
beeton wrote:
Rear group.... if I recall other similar lenses, 4 silver screws for mount, 3 small black ones for shroud, 2 slightly large black ones for contacts, rear cell should unscrew. They may have used locktite type products on the threads. Send a picture if you have one. |
I've no pictures to hand , that's if I took any . When I get chance I will dig the lens out and post some to i.d it , as well as stripping some of it down again to have another look at it .
The rear lens group has haze , hopefully just a layer on the innermost parts that will clean up , and not between two cemented pieces . |
God! How powerful the internet is. Well, I hope I'm doing this right and poster can see my message. Being an old lens, I didn't bother to check online for assistance but after two days battling this rear lens group, I decided to give it a try. Let me assure you I have 100% the same problem and SADLY, the haze is not accessible (at least yet) and that's why I'm here. The haze is between the two exposed sides of the very last set of elements and I've exhausted all the tricks I have trying to extract the elements from the housing to no avail. It looks like they're sealed together but I saw no tell tale signs of Balsam separation. The haze is so bad I could not convince myself it was made that way. It cuts as much as a third or half of the light through it! Anybody with any clue? I'm a very experienced and competent amateur self-taught repaired of these things and I got this far in the disassembly process only to get stuck here. Heeeeeeelp!
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Posted By: Osi
Date Posted: 31 March 2020 at 12:32
I would have liked to attach a photo, but have found no way to do it
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Posted By: neilt3
Date Posted: 31 March 2020 at 12:42
To post a photo you need to upload it to a hosting site such as Flickr . Then copy and paste the BB code into your reply .
------------- see my photostream on flickr; https://www.flickr.com/photos/neilt3/sets/ - http://www.flickr.com/photos/neilt3/ C & C welcome.
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Posted By: beeton
Date Posted: 31 March 2020 at 14:40
I was not able to get to the ear cell. Just no way that I can see to remove that and Sigma service had no schematics. The haze in mine is barely perceptible. Otherwise, lens is very sharp.
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Posted By: Osi
Date Posted: 31 March 2020 at 15:06
Thank you Neilt. So one has to join another online platform just to post a nondescript picture here. How great
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Posted By: Osi
Date Posted: 31 March 2020 at 15:10
Oh, I feel despondent. Please don't make it like a final statement. I've got all these parts lying on the worktable waiting for me to figure out that last piece of the puzzle. I can't accept defeat after all the successes up to this point. Ask elsewhere please. Heeeeelp!
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Posted By: pegelli
Date Posted: 31 March 2020 at 15:33
Osi wrote:
Thank you Neilt. So one has to join another online platform just to post a nondescript picture here. How great | Welcome to Dyxum Osi, I hope you will get your lens fixed.
And unfortunately this "free" site doesn't have the capability to store all the images shown here, cost and server size needed would be prohibitive. So you need one site for your images (there are plenty free ones) and then you'll get us for all the help the membership can provide here 
------------- You can see the April Foolishness 2023 exhibition https://www.dyxum.com/dforum/april-foolishness-2023-the-exhibition_topic142439.html - here Another great show of the talent we have on Dyxum
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Posted By: neilt3
Date Posted: 31 March 2020 at 20:30
Osi wrote:
Thank you Neilt. So one has to join another online platform just to post a nondescript picture here. How great |
It takes a few minutes to sign up to Flickr , and you can store up to a thousand pictures on there . And it's free .
It also makes things easier when you want help . A pictures worth a thousand words , and it takes guess work out of it .
Regards .
------------- see my photostream on flickr; https://www.flickr.com/photos/neilt3/sets/ - http://www.flickr.com/photos/neilt3/ C & C welcome.
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Posted By: Osi
Date Posted: 01 April 2020 at 09:19
I HAVE DONE IT! I came here for help, and now I'm the one who has provided the help! I feel glorious! Ok, I've taken the WHOLE lens apart only to discover I didn't have to. Right at the back of the lens there is an aluminum sealant to the very last lens element and it is the inner part of that group that gets hazy. I severely chipped some metal to succeed in this guesswork (informed as it was nevertheless). Just take the flattest, strongest metal you can find and pry from the inner edge of the outer reaches of the glass and pull the metal up and outward, going around as you do. Alternatively or in addition, stick the narrow strong metal inside the first gap (from middle) an try to pull up also. Don't tell me you won't scratch the metal because it's inevitable -- I don't think they made it to be removed. When you do that, the thin aluminium ring which acts to seal everything up would pop out, followed by an inner separator aluminum, and then the guilty element. THAT'S ALL! Ok, let me go now and see if the haze can be cleaned off. I feel very accomplished. My toughest project has now been carried out. I should add that I feel manual lenses are harder to dismantle than autofocus ones. That's my own experience from doing this thing on over twenty lenses. Cheers
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Posted By: beeton
Date Posted: 01 April 2020 at 13:29
Osi. So, if I understand this procedure, from the rear, after the mount has been removed and the rear plastic ring, the rear cell group is held in by a retainer ring (that's what I call it) and that ring has to be pried out? Can you attach an image of that ring? Many thanks and good luck with the haze.
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Posted By: neilt3
Date Posted: 01 April 2020 at 13:32
It's good your getting it sorted . A few photos would be extremely helpful as if it's the same lens of mine , I've still to dig them out to clean them up .
------------- see my photostream on flickr; https://www.flickr.com/photos/neilt3/sets/ - http://www.flickr.com/photos/neilt3/ C & C welcome.
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Posted By: neilt3
Date Posted: 01 April 2020 at 13:35
If you really don't want to set up a free Flickr account , if you taken pictures , send them to me and I'll put them on mine and post them in this thread . PM me if that suits you better . It gives people a reference and would be helpful .
Regards , Neil .
------------- see my photostream on flickr; https://www.flickr.com/photos/neilt3/sets/ - http://www.flickr.com/photos/neilt3/ C & C welcome.
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Posted By: Osi
Date Posted: 01 April 2020 at 19:03
Guys, I'm so sorry and extremely FAGGED OUT. I spoke too soon and worse: gave a misleading description. I've just freed myself of this worthless job that has consumed a number of days from me after maybe 10 straight hours (since I posted my last message). I've now destroyed any hopes of re-selling the lens (which is what I do). The damage to metal, and sadly glass, is too much to make it salable. I mistakenly said the lens didn't have to be stripped down; WRONG. I had forgotten that what I was looking at as the rearmost elements of the lens were actually the rearmost elements of the INTERNAL CHASSIS upon which the rest of the lens parts are attached. I didn't realise how deeply I'd gotten into this thing. There's still another group behind this group that actually carries the aperture blades itself. While trying to affix the aluminum ring back, I terribly scratched the glass on that difficult part we're talking about. Reassembling, I see it is very visible up till f4 after which the aperture blades cover it. Most tragically and without reason, I disassembled the frontmost elements that are mated by a helicoild path. I introduced dust, grease and all into it and was not able to put both back when it mattered. After maybe 4 hours and really messing up the whole area, I managed to force them together with a huge amount of particles between and they're jammed in and can't be separated (I used a vice, hammer etc). The guilty glass element seems permanently foggy but I did my best and it is now much better, but not 100% clear. Itself even managed to drop on the concrete floor and I almost fainted; but it didn't break. Quite a thin glass by the way
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Posted By: Osi
Date Posted: 01 April 2020 at 19:11
Pls bear with me. I will be back but I've got to attend to so many stuff ignored the whole day because of this job. Yes, I gained experience for more expensive lenses, but this task is not worth doing, considering the value of the lens (mine I manual only, not converted). I will have to take it apart again and post pics to help out. I just wanted to see it take a photo to know if it's worth continuing on, and it did. Will be back soon. Bear with me. I HATE LENS REPAIRS; I PREFER CAMERA REPAIRS
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Posted By: neilt3
Date Posted: 02 April 2020 at 11:36
Thanks for the update . While things have gone wrong , it's still very helpful to know what's happened ( and how ) so it can be avoided . Some photos of it in the process of dismantling to gain access to it would still be helpful . As would your thoughts on if there would have been a better way of doing it .
As I said , I still need to clean mine up !
Cheers .
------------- see my photostream on flickr; https://www.flickr.com/photos/neilt3/sets/ - http://www.flickr.com/photos/neilt3/ C & C welcome.
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Posted By: oldglass
Date Posted: 29 May 2020 at 16:44
Hi there,
Sorry to bump this thread with a not entirely relevant post (manual focus version of this lens instead of A mount). I posted https://www.dyxum.com/dforum/sigma-70210-f-2-8-minolta-md-disassembly_topic138123.html - https://www.dyxum.com/dforum/sigma-70210-f-2-8-minolta-md-disassembly_topic138123.html about my attempts to disassemble and clean this beast of a lens but have not had any luck for nearly 2 weeks so please excuse my cross posting.
Long story short: I've gotten some way into the lens, but have been unable to disassemble the zoom or focusing groups towards the front.
https://i.imgur.com/Fj3e2GM.jpg - This pic shows how it looks from the back of the lens looking towards the front (if that makes sense). It looks to me like the back of a screw there. There are three sticky-outy tabs with holes like this surrounding the zoom group. Is there any way to remove the front shell (seen at the bottom of the picture with the end of the serial number? That seems to me like the only way to access the front elements. Attacking the lens from the front didn't go well for OP at all so there must be a way in that I've not spotted. Although having said that, it sounds like Osi was going in front-side first but it's hard to say how without pictures.
Thanks in advance
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Posted By: Osi
Date Posted: 29 May 2020 at 18:24
Hi everyone. I did send the only picture I took of the completely disassembled lens to someone on here by e-mail but he said he was no longer going to attempt any further to work on it since his wasn't that bad. For the last poster's situation: indeed the focusing lens group is in the very front part. To access it, you will observe that the entire front section has a wider diameter than the focusing grip part. Take your hands from the very front of the lens all the way to the end of that part with same diameter. At the end of it, before the focusing grip is a ring deceptively placed there to lock the front barrel in place. Looking from the back of the lens, turn the ring in the normal anticlockwise direction and voila, the front barrel comes off going further forward. The very first front glass is attached to the rest of the lens by just a black tape! I'm sure you can figure out the rest or else my response will get too long and unwieldy. Please let me know how it went
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Posted By: oldglass
Date Posted: 29 May 2020 at 19:52
Wow, thanks for the quick reply, Osi!
Just to confirm, the ring I should be twisting is the ring https://i.imgur.com/waX8gFs.jpg - pictured here around which I've placed the rubber band? I've tried twisting it a few times and just want to be sure before I tire myself out too much!
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Posted By: beeton
Date Posted: 29 May 2020 at 20:13
Yes, that's the one. It is difficult at first as when you tighten you grip, you may be squeezing it out of round. Try from a few angles. Normal direction (left).
When you get it off, the front barrel will come off (with the af version). The front element AND barrel underneath are held in place with tape. Do NOT take that tape off without first marking the front to rear sections or you will have difficulty aligning them back on.
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Posted By: Osi
Date Posted: 29 May 2020 at 20:21
oldglass wrote:
Wow, thanks for the quick reply, Osi!
Just to confirm, the ring I should be twisting is the ring https://i.imgur.com/waX8gFs.jpg - pictured here around which I've placed the rubber band? I've tried twisting it a few times and just want to be sure before I tire myself out too much! | Thankfully, someone else has chimed in to validate. I was still waiting for your link to produce a picture to no avail. The picture policy of this forum is an Achilles heel
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Posted By: oldglass
Date Posted: 29 May 2020 at 20:30
Osi wrote:
I was still waiting for your link to produce a picture to no avail. The picture policy of this forum is an Achilles heel |
I uploaded my images to an external hosting service (Imgur). Perhaps the forum software mangled the link for you? Try going to i.imgur(dot)com/waX8gFs.jpg
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Posted By: pegelli
Date Posted: 30 May 2020 at 13:53
Osi wrote:
The picture policy of this forum is an Achilles heel | Judging by the amount of pictures posted on this forum on a daily basis it can't be that hard: https://www.dyxum.com/dforum/posting-images-and-links-faqs_topic28010.html - see here for instructions
Btw, good luck with the lens repairs
------------- You can see the April Foolishness 2023 exhibition https://www.dyxum.com/dforum/april-foolishness-2023-the-exhibition_topic142439.html - here Another great show of the talent we have on Dyxum
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Posted By: neilt3
Date Posted: 30 May 2020 at 14:09
pegelli wrote:
Osi wrote:
The picture policy of this forum is an Achilles heel | Judging by the amount of pictures posted on this forum on a daily basis it can't be that hard: https://www.dyxum.com/dforum/posting-images-and-links-faqs_topic28010.html - see here for instructions
Btw, good luck with the lens repairs  |
As explained in March , it's simple and free to start a Flickr account to post images on here , and other places .
I also offered to put the images on my Flickr site and post them in this thread to help others in the future . Not been taken up on the offer though . Shame .
------------- see my photostream on flickr; https://www.flickr.com/photos/neilt3/sets/ - http://www.flickr.com/photos/neilt3/ C & C welcome.
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Posted By: Osi
Date Posted: 30 May 2020 at 15:52
Hi. I did take somebody up on the offer and sent a picture to their e-mail as I recently mentioned. Probably wasn't you then. Please send me your e-mail as a direct message so I can do same. I recently lost a phone containing over 500 pictures of different cameras and lenses under varying stages of disassembly which I use myself. I can regard myself as fairly experienced now and I've always been a competent person (but camera/lens repairs seriously challenged that and I incurred many knocks in the learning process) and I benefitted immensely from online fora like this (still do, hence my appearance here) and I find it fulfilling if I can help others also. I'm just not in sync with the picture policy here. I want to be able to type stuff and click on an attachment tab and upload a picture from my phone. This is what I'm used to. Maybe that would change but for now, I'd rather do it the way I've proposed. We're all in it together (Lol)
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Posted By: neilt3
Date Posted: 30 May 2020 at 16:25
Hi Osi . That's a sickner losing your phone with all the images on , I know how valuable they are for reference .
I've P.Med you my email address .
When I get chance I'll get them on Flickr and posted here so anyone doing a search can find them . Hopefully they will be of help to others . Cheers .
------------- see my photostream on flickr; https://www.flickr.com/photos/neilt3/sets/ - http://www.flickr.com/photos/neilt3/ C & C welcome.
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Posted By: Osi
Date Posted: 30 May 2020 at 17:15
Hi. I have sent a message to the e-mail address you provided, with pictures. They were supposed to be for me only. If I knew I would be sharing them with the world, I'd have done a better job of it. Fun fact: I'm in Nigeria!
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Posted By: Osi
Date Posted: 30 May 2020 at 17:29
neilt3 wrote:
Hi Osi . That's a sickner losing your phone with all the images on , I know how valuable they are for reference . . |
My dear brother, if I lost only my phone with disassembled electronics, that's pretty painful; but it was my entire record of uncountable bookmarked pages,apps, settings, maybe over 19,000 images and thousands of video clipses on various subjects - most simply irreplaceable. I last backed up a full year previously. What I could get hardly represented 10% of what I lost. It feels worse than the death of a human being. I was willing to pay more than the value of the phone to get my information back, but when you misplace your phone in Nigeria, my brother, please forget it. The first thing they do is switch it off and throw away the SIM card and you can't contact them again. They're incapable of considering how vital information in a phone can be.
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Posted By: neilt3
Date Posted: 03 June 2020 at 00:48
Osi wrote:
Hi. I have sent a message to the e-mail address you provided, with pictures. They were supposed to be for me only. If I knew I would be sharing them with the world, I'd have done a better job of it. Fun fact: I'm in Nigeria! |
Hi Osi .
Here are the photos you sent me , hopefully they may be of use to someone doing a search for them .
https://flic.kr/p/2j8fnYC"> https://flic.kr/p/2j8fnYC - sigma lens by https://www.flickr.com/photos/neilt3/ - Neil Taylor , on Flickr
https://flic.kr/p/2j8gPsN"> https://flic.kr/p/2j8gPsN - sigma lens 2 by https://www.flickr.com/photos/neilt3/ - Neil Taylor , on Flickr
------------- see my photostream on flickr; https://www.flickr.com/photos/neilt3/sets/ - http://www.flickr.com/photos/neilt3/ C & C welcome.
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Posted By: beeton
Date Posted: 28 June 2020 at 02:49
I have conquered Mount ZEN. Took much work but I have removed and cleaned the slightly foggy element from my Sigma 70-210 f2.8 Zen
History is written up on the fist page. I was having trouble getting consistent micro-focus correct images as the setting required seemed to jump between +9 and -9. That is a huge range. I found then that there was a little slop in the focus ring and even when focus was on, a slight wiggle of the barrel would throw it off. So, I decided to take the lens apart to see if I had a loose gear or something else causing the play. When taking the lens apart, I removed the front-inner cell, the one with the hazy element, as a group. This was done after removing the front ring from the inside, under the objective. Removing that ring exposes the screws that have to be removed to fully pull out the lens group. This ring is a friction-fit. To remove it, I had to use a plastic cap and a rubber ring (lens grip ring from an old lens) and twist off the ring. Once the screws are out (only the 3 outer have to be removed), the lens group can be pulled out from the back. Once done, you have to remove the retaining ring from the BACK of the metal cell in the same fashion as the front ring but with a smaller cap or insert. You can then pull out the inner cell with the elements. There are 3 elements within- one at front and a doublet at back. To remove the elements itself was a challenge. There is no spanner inset for the front ring or rear. The font had locktite and I had to add a bit of nail polish remover to the gap between the threads top dissolve that (don't get any on the elements). Then, remove the front ring by applying a bit of pressure to the ring face (inside, not top and try to push counter-clockwise. BE CAREFUL not to scratch the element or jab yourself. BEFORE YOU REMOVE THE ELEMENTS, TAKE NOTE OF THEIR ORIENTATION. I put it all back together only to realize I had reversed the front element and had to start over.
Cleaned up the haze and lens works great BUT still that play in focus...will have to be careful on shoots. Took some test images. This is a very nice lens. Sharp and except for some vignetting at 2.8 and a bit of loss in the edges, which almost lenses suffer wide open, very good performer. I will try to post some images.
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Posted By: Osi
Date Posted: 28 May 2021 at 10:58
Haha,what do you know, I'm back to this forum to read up my own advice. I got another similar lens with same haze issue, plus other problems. I forgot the methods I used and ended up making same mistake of dismantling the whole lens. Oh well, at least I've not destroyed the guilty element yet and with this my own guide, I will get to it without scratching or damaging it. This lens is a Sigma autofocus Canon mount 70-210mm f/2.8. Very slow belt-driven autofocus. Aperture driven by gears and 2 gears of 3 broken. The effort I put in these things is just for practice and to up my game; not worth the value of the lens at all
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