Canon FD 300mm F2.8 Fluorite

About two years ago I posted a thread asking for help with the diaphragm of my Canon FD 300 Fluorite. The problem with the diaphragm is that when the shutter is released the diaphragm does NOT return to its fully open resting position. Instead it only makes it back to 3/4 open or 7/8 open. Sometimes only a fraction of a millimeter of the shutter blade extends out of the resting position. This problem is intermittent occurring as little as 1/60 activations of the shutter but sometimes it can occur as often as 1/4. When I first posted the thread with this problem some of the participants in this forum suggested that it sounded like a shutter release linkage problem. I was given a couple of referrals where I could send my lens. The first referral said the lens required a part that is no longer available and returned it to me. The second referral said the sticky diaphragm was caused by the use of an improper lubricant .

He serviced the lens and I found that it seemed to work perfectly. I usually check my analog equipment every 6-7 months and put the lenses on my F-1 and make sure diaphragms/shutters work and don't stick. Yesterday when I put the 300 Fluorite on my F-1 I noticed

after a few dozen cycles the diaphragm began to stick. I could not believe my eyes. Maybe there is a part that is broken/worn and needs to be changed. Maybe the grease applied by serviceperson #2 only masked the problem. If it wasn't because this is a beautiful and rare lens with perfect glass I would not be wasting my time posting this thread. But his lens deserves to have this problem solved. Any help would be greatly appreciated.

 

Raphael

Raphael, my FD 300 2.8 SSC Fluorite was serviced by Steve Swerington at Camera Clinic, due to play in its focusing mechanism. This job included machining some new parts where replacements weren't available. The lens came back working great! Based on his familiarity with the early 300 2.8 I'd refer you to him: www.cameraclinicusa.com

 

I 100% agree with you on the quality and beauty of this lens! Every time its case is opened it still takes my breath away!

I saw that KEH just sold one. I was very tempted, but I do have to eat. Yes, a beauty. Dang!

If you can get to the aperture blades, the littlest, smallest amount of naphtha imaginable (NEVER flood the lens--local hardware store for a lifetime supply for a few dollars) on the blades followed by working the aperture ring, then drying everything out might do the trick.

 

Sometimes just working the aperture ring over and over can unstick it, for a while anyway.

 

If that doesn't work, go to a professional.

NEVER lubricate a lens or camera - most epecially not with the rust-killer oils like WD-40 or other household oils.

Agreed, but it must be pointed out that WD-40 is not an oil. It isn't really even a lubricant. "WD" stands for 'water displacement' and 40 is the 40th formula that was tried before the designers hit upon the success they were after, namely being able to satisfactorily displace water from a mechanism. Lubrication was never more than an additional feature, and wasn't considered by the manufacturer to be the chief reason for using the substance.

 

For camera repair, there is a "household oil" that is suitable -- but only in very small doses -- sewing machine oil. It is very light, but has good lubricity. I would not use it on lenses, however. For lenses, there are lubes made especially for the helicals. But I would caution that one only try relubing helicals if one knows the ins and outs of lens construction. If this is something you want to learn, then try your skills out first on a cheap "throwaway" lens like an old 50/1.8 that essentially has no value. That is certainly not the case with an FD 300/2.8 Fluorite, however. Even though I've repaired many lenses, if that lens were mine, I would be most hesitant about trying to do this repair. I'd much prefer trusting the repair with a qualified professional. Someone like Ken Oikawa comes to mind.

Agreed, but it must be pointed out that WD-40 is not an oil. It isn't really even a lubricant. "WD" stands for 'water displacement' and 40 is the 40th formula that was tried before the designers hit upon the success they were after, namely being able to satisfactorily displace water from a mechanism. Lubrication was never more than an additional feature, and wasn't considered by the manufacturer to be the chief reason for using the substance.

 

For camera repair, there is a "household oil" that is suitable -- but only in very small doses -- sewing machine oil. It is very light, but has good lubricity. I would not use it on lenses, however. For lenses, there are lubes made especially for the helicals. But I would caution that one only try relubing helicals if one knows the ins and outs of lens construction. If this is something you want to learn, then try your skills out first on a cheap "throwaway" lens like an old 50/1.8 that essentially has no value. That is certainly not the case with an FD 300/2.8 Fluorite, however. Even though I've repaired many lenses, if that lens were mine, I would be most hesitant about trying to do this repair. I'd much prefer trusting the repair with a qualified professional. Someone like Ken Oikawa comes to mind.

 

Thanks for the advice using lubricant. The shutter activating mechanism problem of the FD 300/2.8 Fluorite I think is related to something that happens a few years ago. I remember being in a rush to mount the FD 300/2.8 Fluorite on my F-1n and did not have the lens pins lined up properly with the camera when I tightened the FD chrome ring to secure the lens. The lens jammed on the camera body and with some difficulty I removed the lens but was unable to use it for the remainder of the trip. After this I noticed that when the f-stop was changed with any of my FD lenses the "Lollipop " in the view finder would often would get stuck. Eventually I had KEH fix this problem by swopping out the damaged part. I imagine the problem in the F-1n was due to a part that was bent. I am sure the problem in the FD 300/2.8 Fluorite is caused by a bent part in the shutter activating linkage. Does anyone know if the shutter activating linkage of FD lenses are inter changeable? If it is solving the problem is easy and cheap . If not then the part must be machined which means a lot more money.

I just took a look at several FD lenses, both the older breechlock style and the newer New FD style. Only one lens looks like its actuation lever might be machined. The others look like they were made from steel pieces that were pressed and cut into shape. What this tells me is that, if you have a bent lever, it should be able to be straightened without much difficulty. Still and all, I'd have an expert do the straightening -- again, somebody like Ken Oikawa. Also, of the FD lenses I've dismantled, it seems like each one has its own unique design to its aperture and positioning levers, so I wouldn't expect a whole lot of interchangeability there. But that may be due to the fact that the FD lenses I've dismantled have tended to vary considerably in focal length. So, sure, I could be wrong -- wouldn't surprise me if I was. Like with a 24/28 and a 28/2.8 and perhaps even a 35/2.8 -- all these lenses are so close in size, and have the same maximum aperture value, that it seems they might share the same actuating and positioning mechanisms.

I just took a look at several FD lenses, both the older breechlock style and the newer New FD style. Only one lens looks like its actuation lever might be machined. The others look like they were made from steel pieces that were pressed and cut into shape. What this tells me is that, if you have a bent lever, it should be able to be straightened without much difficulty. Still and all, I'd have an expert do the straightening -- again, somebody like Ken Oikawa. Also, of the FD lenses I've dismantled, it seems like each one has its own unique design to its aperture and positioning levers, so I wouldn't expect a whole lot of interchangeability there. But that may be due to the fact that the FD lenses I've dismantled have tended to vary considerably in focal length. So, sure, I could be wrong -- wouldn't surprise me if I was. Like with a 24/28 and a 28/2.8 and perhaps even a 35/2.8 -- all these lenses are so close in size, and have the same maximum aperture value, that it seems they might share the same actuating and positioning mechanisms.

 

Thanks for the feed back. I will certainly pass along this info to the tech who will service the FD 300 f/2.8 Fluorite. I will post the results of servicing this lens when completed.

Thanks for the feed back. I will certainly pass along this info to the tech who will service the FD 300 f/2.8 Fluorite. I will post the results of servicing this lens when completed.

 

Someone recommended that I keep the lens at room temperature instead of my attic where it really gets cold this time of year , I live in CT ,and see if that helps. That did the trick. Last weekend I put the FD 300 S.S.C. on my Canon F-1n and pressed the shutter release well over 500 times and the diaphragm got a little stuck maybe 3 or 4 times . I even made a run of over 125 and did not see a problem. The diaphragm was snappy. So is this problem due to lubrication or a change in the shutter activation linkage. Should a different lubricant be used ? The breech bayonet mount which contains the shutter activation linkage was never designed to be taken apart. It is very complex containing close to 100 tiny ball bearings and if you lose one of those ball bearings to adjust or to replace a part it will make things worse.

 

Raphael

Someone recommended that I keep the lens at room temperature instead of my attic where it really gets cold this time of year , I live in CT ,and see if that helps. That did the trick. Last weekend I put the FD 300 S.S.C. on my Canon F-1n and pressed the shutter release well over 500 times and the diaphragm got a little stuck maybe 3 or 4 times . I even made a run of over 125 and did not see a problem. The diaphragm was snappy. So is this problem due to lubrication or a change in the shutter activation linkage. Should a different lubricant be used ? The breech bayonet mount which contains the shutter activation linkage was never designed to be taken apart. It is very complex containing close to 100 tiny ball bearings and if you lose one of those ball bearings to adjust or to replace a part it will make things worse.

 

Raphael

 

 

Last time I reported that keeping the lens at room temperature for a day or so and then working the shutter release for close to 1000 times reduced the incidence of the diaphragm blades sticking. The diaphragm now sticks rarely and is snappy. So it seems I have resolved the problem. However, there is one last abnormality that I found and wondered if anyone participating in this forum could explain. Using my Canon F-1n (old non-electronic shutter ) I selected B for my shutter speed and while looking through the front of the Canon 300mm F/2.8 S.S.C. Fluorite I turned the F-Stop ring while holding down the shutter release I noticed that the diaphragm dragged a little and sometimes did not close down to the smallest diaphragm setting F/22. Then with the shutter speed still at B I set the F-stop to F/5.8 or F/4 and released the shutter I found the diaphragm would stick and hardly move. If I cranked the film advance and pressed the shutter release in the usual manner the diaphragm released and functioned normally. So something is still not right because my other 300mm Fluorite does not do this. In addition when the shutter speed is at B and the F-stop is at F/22 so that the diaphragm is closed to its smallest setting one can see at the base of the diaphragm blade a tiny area of shinny metal instead of black at the point where the blade pivots. This finding indicates abnormal wear in the diaphragm … none of my other lenses have this. Does anyone know if the diaphragm blades are disassembled for cleaning and service does this require taking apart the shutter release activating linkage/system? Any ideas that explain why the diaphragm is acting the way it does?

 

Raphael

I admit that the 300 Fluorite is a great lens, but do you really need two of them?

I admit that the 300 Fluorite is a great lens, but do you really need two of them?

I was going to give one of them to my youngest son when he shows a tad more maturity!

at the base of the diaphragm blade a tiny area of shinny metal instead of black at the point where the blade pivots

 

Are you sure it is blank metal? Oil entering the aperture unit can often be spotted first at the very outer edges of the blades and it is highly reflective as well.

 

Does anyone know if the diaphragm blades are disassembled for cleaning and does this require taking apart the shutter release activating linkage/system

 

I have not worked on a 300mm 1:2.8 Fluorite myself. This is based on my general experience with servicing other Canon FD telephoto prime lenses: The lens mount assembly which contains the levers and ball bearings has not to be disassembled. The aperture unit will easily separate from the lens mount assembly. The aperture unit is accessed from the front.

 

If it was my lens I would unlock the lens mount while the lens is off camera and work the levers. If I could sense abnormal resistance would take off the lens mount assembly for closer inspection. Otherwise I would give the aperture unit a good cleaning again.

Are you sure it is blank metal? Oil entering the aperture unit can often be spotted first at the very outer edges of the blades and it is highly reflective as well.

 

 

 

I have not worked on a 300mm 1:2.8 Fluorite myself. This is based on my general experience with servicing other Canon FD telephoto prime lenses: The lens mount assembly which contains the levers and ball bearings has not to be disassembled. The aperture unit will easily separate from the lens mount assembly. The aperture unit is accessed from the front.

 

If it was my lens I would unlock the lens mount while the lens is off camera and work the levers. If I could sense abnormal resistance would take off the lens mount assembly for closer inspection. Otherwise I would give the aperture unit a good cleaning again.

 

Sounds like something I might try if I was sure the assembly wasn't rigged like a booby trap. My fear is that I can't put it back together after I take it apart. Has anyone seen this on YOUTUBE?

Sounds like something I might try if I was sure the assembly wasn't rigged like a booby trap. My fear is that I can't put it back together after I take it apart. Has anyone seen this on YOUTUBE?

Just wanted to report back regarding my problem with the diaphragm hanging up on my Canon 300 Fluorite S.S.C. The problem has been fixed and the diaphragm works good as new thanks to Steve at Camera Clinic in Mandam, ND. It did not require any fabrication only thoroughly clean/lubricate the aperture linkage mechanism. Steve did what nobody even wanted to touch including Kanto Camera in Japan. Thanks also to all of you who gave advice and info.

 

Raphael

Edited February 17, 2019 by NLsafari

Glad to hear. Also extremely surprised that you have 2. That was my first foray into truly excellent glass in the early 2000's and it inspired me to try more. It along with a Canon FD 80-200mm f4 L made what I thought were really good Canon FD lenses look like crap! I sold it after a couple of years when a Canon FD 400mm f2.8 L came along at a great price.

Glad to hear. Also extremely surprised that you have 2. That was my first foray into truly excellent glass in the early 2000's and it inspired me to try more. It along with a Canon FD 80-200mm f4 L made what I thought were really good Canon FD lenses look like crap! I sold it after a couple of years when a Canon FD 400mm f2.8 L came along at a great price.

My first 300/2.8 was a present from my wife it was the lens with the problem. The second I picked up on EBAY about 6 years ago for about $500 the glass is perfect only needed cleaning by Steve Serota who passed away a number of years ago. When my youngest son who likes photography learns to take care of his equipment I will give it to him. I gave him a nice Tamron 50-300 zoom and it was junk after a about year.