Jump to content

Seeking Canon EF Camera Information


timwitt

Recommended Posts

4 hours ago, PO911 said:

I am still wondering, how the f-stop-metering (position of needle in viewfinder) is transformed into the correct aperture setting on the lens? Has to be some sort of delicate mechanics. Anybody here can explain this?

Thanks, Arno

Thinking back I'm pretty sure Canon used the "trap needle" system.  Once the meter needle stops moving and is set at a particular F-stop, an arm gently moves down and "senses" its position.  Through a series of linkages, etc. that position is transferred to the lens, so when you hit the shutter button, the F-stop you see in the finder is what the lens stops down to.  

Link to comment
Share on other sites

  • Replies 152
  • Created
  • Last Reply

Top Posters In This Topic

The "A" or "○" position on the lens aperture ring is the magic. On the back of the fd lens, there is the aperture signal/control arm located on the side, in a long slot. As you turn the aperture ring, the arm rises or falls with the aperture. This arm couples with a lever at the side of a manual, match-needle metering  camera's mirror box that moves the circle that indicates the f-stop in the viewfinder.

When the lens is set to "A" or "○" on the EF, New F-1, F-1 with Servo EE Finder, and AE-1, the signaling arm becomes a control arm. A tiny little pin in the lens pushes a button in the camera's lens mount ring area which signals the camera to go into auto mode. When the shutter is fired, the camera closes the aperture and the control arm drops as usual. But the corresponding arm on the side of the mirror box stops and locks at a level that corresponds to the f-stop recommended by the meter. The arm in the mirror box thus stops the lens' control arm at the correct f-stop. Until the lens is set to "A" or "○", the arm in the mirror box is unused. That is why there is no manual match-metering in the auto exposure camera bodies besides the New F-1.

It is amazing to me that Canon was able to convert the R/FL mount into the FD mount.

Edited by steven_endo
Link to comment
Share on other sites

1 hour ago, steven_endo said:

It is amazing to me that Canon was able to convert the R/FL mount into the FD mount.

Well, don't confuse the actual breechlock mount with the R/FL/FD aperture mechanisms.  The mount just attaches the lens to the camera and is identical among the three, but the aperture actuating mechanisms are different, especially for the R-mount lenses, which share nothing with their FL/FD cousins.  

Link to comment
Share on other sites

Oh, I realize that. But to go from nothing (?) in the R, to one auto stop down lever in the FL, to the various controls on the FD (including one "reserved" pin that was never used) is fascinating.

Makes me wonder if Canon was planning the FD mount when they designed the R or FL mounts (possible or probable?) or if they just found a way to stuff all the extra pins inside the mount.

And then, of course, dumping everything to make the EF mount which was a sad day for me...

Edited by steven_endo
Link to comment
Share on other sites

Thank you Steven, Jim, for the good explanations! Good to see that there are some more EF enthusiasts here.

It is fascinating to see how the meter-needle position is transfered into the correct corresponding aperture-setting. All without electronics, just pure precise mechanics. I spent at least one hour last night just to examine all those levers...

Next thing, I will remove the galvanometer, since the aperture scale in the viewfinder seems to be stuck or disengaged. The more I deal with my "for parts only" EF, the more I am reaching out to get her back to life again 🙂 Fortunately the PO didn´t break anything as far as I can see.

Have a great week.

Arno

Link to comment
Share on other sites

  • 2 weeks later...

An old Copal Square S shutter never fails. 😄

I got the shutter to work as intended. Initially the mirror stayed open and the shutter did not close. The closing blades were somehow stuck (like oily aperture blades). Probably someone had sprayed some sort of lubricant in the past.

Long story short. I gave the whole thing, shutter blades and the complete shutter mechanism a good rinse with cleaning solvent for electronic circuits (Kontakt 601) that leaves no residue and does not harm any materials. After that, the shutter fired again with no problems. 

Only thing that does not work properly is the self timer. There are two tiny (very tiny) hair-springs that cock two small levers in this clockwork and those are missing. Does not affect the rest though. Anyone has a close up shot in high resolution of the shutter by any chance? Can´t find anything good on the net...

Thanks and stay tuned

Arno

 

 

 

Link to comment
Share on other sites

  • 1 year later...
On 1/26/2023 at 11:43 AM, PO911 said:

An old Copal Square S shutter never fails. 😄

I got the shutter to work as intended. Initially the mirror stayed open and the shutter did not close. The closing blades were somehow stuck (like oily aperture blades). Probably someone had sprayed some sort of lubricant in the past.

Long story short. I gave the whole thing, shutter blades and the complete shutter mechanism a good rinse with cleaning solvent for electronic circuits (Kontakt 601) that leaves no residue and does not harm any materials. After that, the shutter fired again with no problems. 

Only thing that does not work properly is the self timer. There are two tiny (very tiny) hair-springs that cock two small levers in this clockwork and those are missing. Does not affect the rest though. Anyone has a close up shot in high resolution of the shutter by any chance? Can´t find anything good on the net...

Thanks and stay tuned

Arno

 

 

 


Let’s not forget that the data requested by the OP several years ago is to nail down the production history of the EF.

 

 

Edited by Bettendorf
Link to comment
Share on other sites

13 hours ago, gwhitegeog said:

Yes, it was a long series of posts, I wasn’t sure. Technically it was made ‘74 to ‘78. But did we want to know the production run? 

Well, I tried to delete that post because it really doesn’t matter any more, but it timed out in the middle of it. 
Tim Witt was wanting to gather info on S/N, date of manufacture, and if yours had the newer focusing screen, in order to determine when that change occurred along with the number and date of the last one produced.

The post above yours by Sheperd is like what he was after.  It’s still a good read on a great camera!

Link to comment
Share on other sites

2 hours ago, gwhitegeog said:

Mine is P821 code and with split image / microprism focussing screen. 

Great!  Now if you just add your S/N to that info, you too can be a member of this 16 year old, Black Beauty thread Club.  😎

If you desire you can post it like this, 2793XX.

Link to comment
Share on other sites

  • 1 month later...

I’m glad I found this very entertaining thread. Not much info out there on the EF. Played with several AE-1’s and a number of A-1’s, of which I still have and use. My EF is #378950 date is Q1031 (if I’m reading it correctly).

The shutter dial on mine moves very sluggishly, but has full range. Everything else function great. I find myself picking up the A-1 and the EF much quicker than my 5D Mk2. Just love that solid mechanical feel. I probably need to get the EF serviced, but I would miss it too much. 

Link to comment
Share on other sites

Yes, a great camera. Actually, my EF is currently with my camera technician in Lisbon. It's having a once over and some new light seals, along with a classic 24-35 f3.5 SSC lens getting a service. The EF probably needs no work, I believe is still functioning well after 50 years! It was one of their best cameras of the era and a bit below the radar and not so popular or as many made, I would assume. 

Link to comment
Share on other sites

10 hours ago, gwhitegeog said:

......It was one of their best cameras of the era and a bit below the radar and not so popular or as many made, I would assume. 

There is an EF database out there with EF serial numbers.  From memory, about 300,000 cameras were made.  Not bad considering the EF was a premium-priced camera.  It also had no chance when the AE-1 came out two years later.  You could buy a much smaller and lighter camera (a big deal in the mid-70's, thanks to the OM-1) which was also substantially cheaper than the EF.  I had an EF back in the 70's, but sold it and bought an F-1 (which I still have).  But I still admire the EF, just an excellent camera.

Link to comment
Share on other sites

300,000 sounds about right. In those days they tended to make fewer but over a longer period of time. 1 million Nikon Fs were made from 1959 to 1970. So, 300,000 in about 5 years for the EF sounds correct. 

Link to comment
Share on other sites

PS today's models barely last 18 months before they are upgraded. As I said to my technician in Lisbon, we can still fix 50-60 year old cameras today (more or less). I am not sure 'nostalgia enthusiasts' will be able to fix today's electronic mirrorless cameras in say, 2080! 

Link to comment
Share on other sites

There's an earlier thread in this FD forum that has plenty of Canon EF serial number and date code info.  Looks like production ended in July, 1977.  Several cameras were in the 420XXX serial number range, meaning about 320,000 made.  Curiously, there's a pic of an EF with a 502XXX serial.  Seems way too high, but it was common practice for Canon to make replacement covers for damaged cameras, all using very high serials.  You see the same thing with the F-1 and Canon 7 rangefinder cameras.

Link to comment
Share on other sites

Hi Jim,

Yes, it's interesting isn't it - I was 13 in 1977 and remember that era well; I was just getting into photography with my own Russian Zenit SLR and borrowing my dad's Canon F1. We were about to be taken by storm with compact electronic SLRs - the Pentax ME, Olympus OM-10, Canon AE1 (and then A-1) and we should not forget the awful AV-1 too. But most of those cameras have given up the ghost with their shutters or PCBs but EFs and F1s with their mechanical copal shutters are still good?

Gary

Link to comment
Share on other sites

13 hours ago, jim_bielecki1 said:

There's an earlier thread in this FD forum that has plenty of Canon EF serial number and date code info.  Looks like production ended in July, 1977.  Several cameras were in the 420XXX serial number range, meaning about 320,000 made.  Curiously, there's a pic of an EF with a 502XXX serial.  Seems way too high, but it was common practice for Canon to make replacement covers for damaged cameras, all using very high serials.  You see the same thing with the F-1 and Canon 7 rangefinder cameras.

Can you post a link to that Jim?  I can't find anything earlier than this one.

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now



×
×
  • Create New...