Canon FD/FL compatibility?

I can't find an article on the net that's of much help. Can FL lenses be used on FD bodies and vice versa? And I've seen some older lenses as BL. What is that?

All FL-lenses fit on all FD-bodies.

However: FL-lenses do not have a max. aperture indicator. Thus auto-exposure is not possible aiming with an open lens.
Stepped down however auto-exposure is possible in the stepped-down auto-exposure mode (if the camera offers this feature).

Stepped down also manual metering is possible.

There are a few FL lenses that will not fit on some FD bodies, you can find that in the manual of each body.
The A-1 , I know shouldn't be connected to a 58mm f1.2. I have tried this, and did not experience any issues, but The meter wouldnt react any lower than 1.8 on my camera. Dunno why.

Any FD lens can be mounted on any Canon FL body and will be fully functional with no modifications. "Fully functional" means that stopped down metering and the automatic aperture mechanism are identical in operation. The Canon FL/FD lens mount is usually referred to as a "breech lock" ("BL") mount. FL lenses and early FD lenses have a separate rotating chrome ring that locks the lens in place. In 1979, Canon redesigned their FD lenses to eliminate the separate chrome ring. On these "New FD" or "FDn" lenses, the entire barrel of the lens rotates to lock the lens in place. This redesign was only cosmetic. The old FD lenses with breech lock rings and the New FD lenses are fully interchangeable.

With respect to using FL lenses on Canon FD bodies, most FL lenses will mount and operate with no problems. There are a handful of exceptions that depend on the specific body in question, so you'll need to read the user's manual published by Canon for that specific model. A couple of lenses may cause physical damage if mounted, while others will mount but will not meter properly. I believe that the metering problem is limited to the newer A or T series cameras. Trythis, the back of the FL58mm f/1.2 lens extends deeper into the mirror box and is probably interfering with the maximum aperture signal pin, fooling the camera into thinking that f/1.8 is its maximum aperture. To get proper exposures at f/1.2, you'll need to determine the proper expose at f/1.8 in the stopped down mode, then go to fully manual mode and adjust the shutter speed for the additional stop.

Note that the Canon T-50 was designed specifically for FD lenses. While you can mount and use an FL lens, its functionality will be very limited. Also, when mounting an FD or New FD lens on an FL body or FD body that does not have automatic exposure, make sure that the aperture ring is not set on the green "A" or green "O."

AgX said:

All FL-lenses fit on all FD-bodies.

Click to expand...

(Even Bob Shell and Günther Richter said so...)


I have to correct myself: there are combinations that (stated by Canon) do not allow use at all.

One might think at the barrel or rear lens element protruding back too much. However this problem is stated for the AE-1 Program but NOT for the AE-1. To my knowledge the mirror box of both cameras is identical.

Can someone comment on this?


Furthermore there are some combinations (stated by Canon) that do allow use but not metering, even not in the stepped down mode for "mechanical reasons".

Can someone comment on this?

FL/FD lens differences

-) both versions have identical flanges for fixing the lens to the body

-) both versions have a similar lever for the body to actuate the closure of the aperture to the pre-set value.(Pre-set at FL-lens by setting manually the aperture ring, and at FD-lens by either setting this ring in manual mode or by letting the body set the aperture-simulator [s. beneath]

-) the FD version has additionally a bolt indicating the max. aperture of the lens (necessary for all open-aperture metering to make the body know to what value to reference the metered luminance to)

-) the FD version has additionally a lever (aperture-simulator) that is actuated by the body to pre-set the value to which the aperture will be closed in automated mode, or that indicates the body the value of the aperture pre-set at the aperture ring of the lens in manual mode.


As one can see there is no indication of mismatch when using either type of lens at an FD-body. There is further no hint at the (semi-official) literature on FD-cameras I got, only those hints in at least one manual.

BL is breech lock - it's a metal ring around the lens where you mount it to the camera. After you fit the lens into the body you twist the locking ring (obviously to keep the lens secure) and twist it the opposite way to remove the lens.

Oops double post

Thanks to all. It seems on the net every other website has a wealth of info about Nikons, but can't seem to find all that stuff on the other brands.

In this very case even the pre-internet media are contradictory.

In general a very good source for answers to a lot of Canon FD related questions can be found at

http://www.mir.com.my/rb/photography/photography.htm

AgX said:

(Even Bob Shell and Günther Richter said so...)


I have to correct myself: there are combinations that (stated by Canon) do not allow use at all.

One might think at the barrel or rear lens element protruding back too much. However this problem is stated for the AE-1 Program but NOT for the AE-1. To my knowledge the mirror box of both cameras is identical.

Can someone comment on this?


Furthermore there are some combinations (stated by Canon) that do allow use but not metering, even not in the stepped down mode for "mechanical reasons".

Can someone comment on this?

Click to expand...

Some FL lenses are stated by Canon to press the lens speed indicator rod of the body unintended by means of their barrel. But at least this behaviour should be identical for all FD-bodies.

Note that to use an FD lens on an FL camera in stopped down metering mode (where as you move the aperture ring, the aperture is actually moving open and closed), you need to move the lever on the back of the lens into the locked ("FL mode") position. With most breechlock lenses this is accomplished by pressing the bigger silver lever until you feel resistance, and then pushing it a little farther to lock it into place. (Remember to undo this before mounting it on an FD camera again!) For a couple of breechlock lenses, this is accomplished by moving the silver lever and then flipping another little swinging lever on the back face of the lens into the position that locks the first lever.

For new-FD (bayonet mount) lenses, Canon actually abandoned the ability to put the lenses into FL mode, probably figuring who at that point would still be wanting to do that. Well apparently somebody did, because they came out with a little tiny piece of plastic to fix this. You slide the big silver lever over, then slip this little piece of plastic on it, and it wedges it to the far side in the slot and holds it in place. Presto! Note that these are incredibly hard to find at this point, so a lot of people just wedge the lever over with a bit of Q-tip or something. (This comes up when people are trying to use FD lenses on those spinning-ground-glass lens adapters for digital video cameras.)

Duncan

frobozz said:

For new-FD (bayonet mount) lenses, Canon actually abandoned the ability to put the lenses into FL mode, probably figuring who at that point would still be wanting to do that.

Click to expand...

That locking of the aperture actuator would also be necessary if the new-FD lens would be used on a non-automated bellows or in reverse-stand without automatic aperture adapter.

According to the instruction manual of the New Canon F1 the following lenses can't be used with it-
FL 19mm f3.5
FL 58mm f1.2
R 50mm f1.8
R 100mm f3.5
R 100mm f2.8