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Kronik
Tinkerer
Username: Kronik
Post Number: 3
Registered: 02-2011
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, June 09, 2011 - 04:16 am: | 
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I just received this great looking Canon FD f1.4 50mm lens by mail today, however, I can't get the aperture blades to show.
I've tried setting my Canon AE1 to B and look through the back door, going through all the apertures. I tried setting the lens to automatic. The aperture just stays wide open. I tried stopping it down with the button on the lefthand side: no effect.
When I tilt the lens, I can hear something moving, which sounds like it might be the blades (it's not moving around, it stays in place).
So... any advice on how to procede? Is there anything else I can try before going to a repairshop? |
Berndtotto
Tinkerer
Username: Berndtotto
Post Number: 7
Registered: 03-2011
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, June 09, 2011 - 09:20 am: |
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I think, all Canon FD/FL type lenses do have some kind of lever on the back side ( the side, which is facing the camera ). You can hold it aside with your hand and the blades should move, when moving the aperture ring. If that works, the lens is okay and hasn't just been properly mounted to the camera, which can often happen, especially when using adapters.
Repairshop ? That might probably not be worthy. Canon FD f1.4 50 mm lenses are one of the cheapest available.
Hope, that it is not broken. Good luck !!! |
Brcamera
Tinkerer
Username: Brcamera
Post Number: 98
Registered: 08-2010
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, June 09, 2011 - 10:13 am: |
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Although you can not see the aperture move with FD lenses when they are off the body (unless you move the bayonet ring to lock position or turn the inner mechanism on later models), your technique of mounting the lens on the camera and looking through the rear should show the aperture stopping down. My guess is that the diaphragm blades are quite full of oil, very common on this lens, and are stuck in the open position. The noise you hear when tilting the lens is most likely the ball bearing race on the rear mount. If the blades are oily, it takes a fairly deep disassembly to remove the blades and clean the mechanism of oil. |
Old_school
Tinkerer
Username: Old_school
Post Number: 75
Registered: 04-2011
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, June 09, 2011 - 12:57 pm: |
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K:
There are two levers on the back of the Back side of the Canon FD lenses. One is to actuate the aperture, the other I believe is to index the F stop to the meter system. When the one lever is moved with you fingers to its full range it will lock into position & the lens becomes a manual stop down like the Pentax M & A feature on some of their lenses. Not sure the reason for this,but would SWAG it that this allowed the lens to be used on the older models with stop down metering or on bellows & such or reverse mount. The group above has stated some very posible explanations as to testing & probable cause also the spring or one of the rings controlling the action may have jumped from an impact. If you have another FD lens handy, you can check the action of these levers for proper function & note the little pin that locks the breech mount may need to be depressed to rotate it, then rotate it back into position till it clicks & locks before trying to put the lens back on the camera. At this time don't have a lens on hand to give the precise lever positions, but I think the lever to the left (with the index pin on top or the reference line for focus) & the one on the bottom actuates the diaphragm. As the lever in the bottom of the camera body lives there to kick that little guy when called to duty. And on the FTB there is a lever on the side of the mirror box (rewind knob side) that links to the meter.
If you can't sort it out, & you can send it back & try another one.
Maybe this helps & maybe it makes things more confusing!
The Best Mike..... |
Cooltouch
Tinkerer
Username: Cooltouch
Post Number: 105
Registered: 01-2009
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, June 09, 2011 - 08:22 pm: |
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Hrm . . . first things first. Is it a breech lock FD or a "New" FD? That is, does it have a dull chrome knurled ring at the back of the lens that you turn to get it on or off, or do you rotate the lens to mount/dismount and push a little button on the lens to remove it?
Knowing which one will tell you which procedure you need to follow to attempt to manually stop down the lens. But I can say this -- if you tried stopping down the lens using the stop-down lever on the front of the camera, and the aperture blades didn't move, then you've most likely got oil on the blades and the lens will need to be disassembled and cleaned. Also, if you shake the lens there shouldn't be any rattling noises. |
Dsides
Tinkerer
Username: Dsides
Post Number: 44
Registered: 04-2009
Rating: N/A
Votes: 0 (Vote!) | | Posted on Friday, June 10, 2011 - 12:05 am: |
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I fixed mine thanks to Rick:
http://rick_oleson.tripod.com/index-161.html |
Kronik
Tinkerer
Username: Kronik
Post Number: 4
Registered: 02-2011
Rating: N/A
Votes: 0 (Vote!) | | Posted on Friday, June 10, 2011 - 04:46 am: |
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Thanks everyone for the info.
It is a "new" FD, but moving the levers doesn't do anything. Compared to other FD lenses: they don't actuate anything either, and they also don't make the same noise.
I'm not much of a tinkerer, so I think this is just going back :/ |
Glenn
Tinkerer
Username: Glenn
Post Number: 932
Registered: 07-2006
Rating: N/A
Votes: 0 (Vote!) | | Posted on Friday, June 10, 2011 - 08:07 am: |
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Dear dear, I do wish people would think before putting 'pen to paper! As people who have repaired this lens already know, you SHOULD hear a faint 'rattle' sound when you gently shake or rotate it swiftly back and forth around the optical axis.
This lens is fitted with what Canon described as the nFD type 1.4 rear mount assembly - the assembly was fitted to other 'high end' nFD lenses but first appeared on this particular lens (50mm f1.4), hence the description. The 'rattling' sound is made by approximately 106 1mm ish loose packed ball bearings, that support the aperture actuating levers. If there is no rattle the balls are either missing (common DIY repair fault) or are gummed up with grease which should not be there. The 1.4 mount reduces the amount of friction found in the standard 1.8 type assembly (fitted to the 'amateur range' of nFD lenses) and gives much better aperture function response at higher shutter speeds.
When servicing lenses fitted with the 1.4 assembly, make sure you remove the complete actuating assembly from the lens in one piece. There is hardly ever any need to disassemble this item, a flush out with naphtha will remove any debris/grease present.
As Bill has stated - when the nFD mount is off the camera, the aperture actuating levers are locked and one cannot test the working of the mechanism. To work the aperture mechanism in nFD lenses off camera, you need the Canon Rear Macro Hood. This item looks like a rear lens cap with no bottom and is inserted into the lens mount and rotated until the square release button clicks. This frees the aperture mechanism and allows manual setting - obviously used when lenses are reversed for macro work, its use as a 'test tool' was an added bonus. The 'bottomless rear cap' is the clue to a simple replication of this Macro Hood - just take a proper Canon nFD rear cap ( these are the ones with the serrated finger grips around the rear edge) and cut out the plastic end. This will produce a very good substitute for the genuine item. |
Br1078lum
Tinkerer
Username: Br1078lum
Post Number: 101
Registered: 11-2010
Rating: N/A
Votes: 0 (Vote!) | | Posted on Saturday, June 11, 2011 - 01:40 pm: |
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106 ball bearings? That lens has got to be a nightmare to fix.
PF |
Ronnies
Tinkerer
Username: Ronnies
Post Number: 20
Registered: 09-2009
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, June 12, 2011 - 02:59 pm: |
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I have a nFD 50/1.4 which can be rotated very slightly about the optical axis. Everything from the aperture ring forwards will slightly rotate. There is no forward/back play at all. Having heard about the ball bearings I may just live with this as the lens seems to work fine otherwise ! Or is dissasembly fairly straight forward? I'm assuming I need to go in from the front.
Ronnie |
Glenn
Tinkerer
Username: Glenn
Post Number: 933
Registered: 07-2006
Rating: N/A
Votes: 0 (Vote!) | | Posted on Monday, June 13, 2011 - 01:14 pm: |
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The ball bearings in the rear of the lens are no problem if you remove the aperture actuating lever assembly complete. You remove the three radially placed crosshead screws in the finger grip ring, that retain the stainless steel bayonet ring - these screws are torqued up really tight, so use a proper sized bit in a handle with a large grip. lever out the ring and then lift out the actuating assembly complete. Never remove the three small radially placed screws that are in the portion of the actuator that protrudes beyond the stainless bayonet ring - unless you want to search the carpet with a magnet for a week collecting balls.
Ronnie I would leave the lens alone unless the focus is rough or sloppy. There is no actual adjustment on the 'key' that stops the inner helix rotating as you focus the lens in and out, regreasing will help by filling up the 'keyway' for a while, but this is not really a problem so leave well alone. |
Ronnies
Tinkerer
Username: Ronnies
Post Number: 21
Registered: 09-2009
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, June 15, 2011 - 02:47 am: |
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Thanks Glenn. Focus operation is fine it's just the whole lens seems to rotate slightly on the mount. Only the black part where the three screws holding the bayonet ring in are doesn't rotate.
I'll leave well alone I think.
Ronnie |
