Relationship between Canon RF and FD lenses?

[squirrel$$$bandit]

Howdy, not sure where to put this, so I'm putting it here. Does anyone have a working knowledge of the relationship between classic Canon rangefinder lenses and their FD counterparts? Are the formulas the same, or did they change for the SLRs? I'm particularly interested to know if the FD 100/2 is optically similar to the rangefinder 100/2, and if not, how they compare.

Thank you

 

[Mackinaw]

Remember there’s a lot of space, time-wise, between the FD lens line and Canon rangefinder lenses. Both the “R” series and “FL” series of lenses pre-dated the FD line. I don’t believe any FD lenses share the same optical formula with their rangefinder lens counterparts.

As for the FD 100/2.0 and the LTM 100/2.0, they have different optics. However the R 100/2.0 (for the original Canonflex) does share the same optical formula as the LTM 100/2.0 version.

Jim B.

 

[raid]

The Canon Museum may have some information that is useful to you.

http://global.canon/en/c-museum/

 

[Fixcinater]

The late black RF LTM 85mm f/1.8 has the same optics as the FL 85mm f/1.8.

The 100mm f/3.5 was one of the few that got an adapter lens mount to fit on the R and FL cameras. You could mount the head of the LTM version onto this adapter and use it on the SLRs. The 85/1.9 and 135/3.5 also had adapters to do this and this group of lenses were some of the first to get put on the SLRs.

I believe the 200 Mirror Box lens and the FL 200/3.5 had the same optics but I don't have first hand experience with those.

 

[squirrel$$$bandit]

Good info, thanks, everyone!

Dumb Q, why does that Canonflex 100/2 have...two aperture rings?

 

[Mackinaw]

Good info, thanks, everyone!

Dumb Q, why does that Canonflex 100/2 have...two aperture rings?

The R100/2.0 is a “Super-Canomatic” lens with an automatic diaphragm (lens opens up after exposure….apparently a big deal back in 1959). The primary aperture ring is what you use to set the shooting aperture. The secondary aperture ring manually stops the lens down so you can check depth-of-field.

It’s easier to use than to explain.

Jim B.

 

[View Range]

It is my belief, but I can in no way prove it and I know it is heresy, that certain S, R and FL lenses were built on the same assembly lines and shared the same serial number sequence. I first started thinking this way when looking at the 135mm f2.5M lens for Mirror Box 2 in Peter Kitchingman's book. There is no way that nearly 10,000 of the 135mm f2.5M lenses were made. That is 3x the total production of the Leitz 125mm f2.5 Hektor. Anyone who has ever tried to find a 135mm f2.5M knows how rare they are. You can have your pick of Hektors at anytime on E-bay. We have also seen discussions on this forum about 19mm f3.5 S lenses with FL name rings. This mistake could not happen if the production lines were separate.

I have collected serial numbers for 135mm f2.5 and for 200mm f3.5 lenses in S, R and FL mounts and I never found a duplicate number in either focal length. My sample size is pretty small though so it proves nothing.

I know of many errors in the Canon History Museum so the information there has to be used with caution. Peter's book is a far more accurate source.