[SOLVED] Problem Mounting Canon FD Lenses

[xaprb]

I feel like I'm going slightly crazy because I'm having trouble mounting some FD lenses that I'm sure I've mounted before. In order to help me troubleshoot, I've gone through my collection and pulled out all my FD lenses, and I can't mount a single one of them to either of my FD adapters!

The issue is that the adapter can't move all the way against the mounting surface due to the AE switch pin. The adapter runs into this pin, which doesn't depress. This is the case with all of my FD lenses. Here's a diagram from the mir.com.my page on FD lenses.


#1


The AE pin is indicated on that diagram, and here's a photo of one of my lenses with the pin encircled in red:


#2


When the adapter (Novoflex) is lined up to register with the lens correctly, the AE pin meets the flange where I've circled here:


#4



My understanding of the correct way to mount an FD lens is:

1. Open the lens's aperture to the green circle that's to the side of the aperture markings.
2. Rotate the lens's breechmount collar until the red circle aligns with this green circle. The collar is now "cocked" as it's springloaded.
3. Place the adapter into the lens, with registration marks aligned so the attachment slot fits over the positioning pin. See photo below. The lens's collar releases when a large "button" under the collar about 9 o'clock in the photos above is depressed, and partially rotates under the tension of the spring; then I manually rotate it a bit further to snug up the fit.


#5


I also have a Kipon adapter, which has an additional lock/open ring on the adapter, and I can't mount any of my lenses to that one either. This ring is just an added safety and the adapter is otherwise identical to the Novoflex.

I've fidgeted with the various levers and collar positions on the lens, and tried to see if any of them allows the AE pin to depress, but I haven't found a position that does that. Clearly there MUST be one, because otherwise none of these lenses would ever have fit onto my adapters, yet they definitely have! The diagram from the above-mentioned website shows the camera's mount has a hole for the AE pin to fit into, which doesn't exist on my adapters.

I'm sure I can't be the only one with this problem, as I've searched the internet and found a lot of threads on stuck/jammed lenses and so on, but none that seems to mention this problem specifically. Most of what I've found deals with lenses jammed due to the aperture ring being incorrectly positioned, and therefore mounted so the Automatic Aperture Lever is on the wrong side of the pin that engages with it. I haven't found any information about the AE pin and what its correct functioning is.

As I say, I feel I've fallen into a parallel universe. I've used this adapter with a half dozen FD lenses for a year. How I can suddenly not be able to mount any of them is beyond my ken.

[caspert79]

I have only one Canon FD lens, and I decided to never take my adapter off anymore 😊.

[stevemark]

[Blazer0ne]

...

[connloyalist]

Judging by the pictures you have a Novoflex adapter, so I thought I might jump in here

On my Novoflex FD adapter I do the following (which works well for me and I seem to remember this is what the Novoflex instructions say) -

With nFD lenses (bayonet):
Align the red dot on the lens with the white dot on the adapter. With the lens contacting the adapter, turn the lens so the red dot on the lens aligns with the red dot on the adapter. Doing this you should feel the aperture pin on the lens cock against the pin in the adapter. When the two red dots align you should feel the lens click in to the adapter. Then rotate the lens back towards the white dot on the adapter until it locks, some distance beyond the white dot.

With "old" FD lenses (breech):
Same basic procedure. Align the red dot on the lens with the white dot on the adapter. With the lens contacting the adapter, turn the lens so the red dot on the lens aligns with the red dot on the adapter. Doing this you should feel the aperture pin on the lens cock against the pin in the adapter. When the two red dots align you should feel the lens click in to the adapter. Then rotate the lens collar (breech) towards and beyond the white dot to lock it.

Using this method there is no need to take the current aperture setting into account and the green dot does not come into play (I think it is for camera auto aperture on FD cameras?).

Hope this helps.

Regards, C.

[Blazer0ne]

...

[xaprb]

Mystery solved. Thank you all for your help! When I rotate the aperture ring to something other than the green-circle, the AE pin pops in and I can mount the adapter. I think I tried every combination of everything I could think of, except for that.

I still feel gaslighted by my former self: I can't remember ever mounting lenses any other way than setting their aperture rings to the green-circle. How I did this in the past remains inexplicable to me. Maybe my memories of mounting these lenses are really unreliable?

Just another day in which FD mount traumatizes me with its arcane complexity, I guess!

[xaprb]

For some comic relief, this is how I feel about Canon FD mount, in general. Hope I'm not offending anyone who feels differently!

[caspert79]

[55]

[casualcollector]

If the aperture ring is in the auto exposure position, A green circle or "A" just past minimum aperture the little pin extends. This prevents the lens being placed in auto exposure mode on non auto exposure cameras. It also prevents mounting on non auto exposure cameras if lens is set to auto. Never had a problem with Canon R, FL, FD or New FD. Years of experience and starting out with a Canon.

[Neil Chiavaroli]

Ran into the problem of not being able to mount FD lenses. I have AE-1, T90, FTb, and EF bodies. The FTb won't accept an FD lens IF the aperture ring is set to "A" or a green dot. The other bodies don't care. Checked with several lenses.

[Lightshow]

I do like my FD lenses, but Canon went too far trying to complicate the mount so as to protect their ecosystem.
EF was the next logical step in protectionism though that only lasted a short while till 3rd party lenses hit the market.

[Olivier]