Leica LTM Leitz Flash contact: COOIF vs. COONT ?

Leica M39 screw mount bodies/lenses

Luddite Frank

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I am keeping an eye open for a Leitz "clip-on" flash contact to use on my Barnacks.

It would appear that Leitz's broad category was "VACU", but there were (at least) two versions:

COOIF, and COONT

Does anyone know what the difference is, and which version fits which cameras ?


( Does the difference have to do with whether there's a slow-speed dial on the body front, or what ? )

Thanks !

LF
 
Hmmm....


So either version should funtion on "any" I / II / III Barnack, and its -a, -b, -c variants ?

Leitz made the CAVOO-A all the way to the CAVOO-F

each variation was for cameras up to the Leica III in the case of the CAVOO-A

The CAVOO-B for the IIIa and IIIb

and several versions for the "c" model Leicas, from CAVOO-C to CAVOO-F

the cammed dial came in four different versions depending what model Leica it was for.

Vacu2-01.jpg
 
I've taken a kind of interest in these early flash devices over the last year or so, and here is what I have learned so far about them.

I have found this information in Dennis Laney's "Leica Accessory Guide 2nd Edition" published by Hove Collectors Books.

The COOIF and COONT were part of the CAVOO flash accessory for non flash synched Leicas, being available from 1951-53. Each was one of the two kinds of synchronizers units which were screwed onto the shutter release, and a special replacement CMVOO cam shaped shutter speed dial was used in place of the normal round one, to close an electrical contact on the synchronizer.

The COONT was for use with electronic flash and had a small sine wave engraved on it's back. Xayraa33 has a great photo of this COONT synchronizer in the note number 4 directly above mine here.

The COOIF looks the same as the COONT, but was used for long delay PF type flash bulbs. It was engraved "Vacu" on the back.

I have not learned how to adjust the timing of them yet, or know what shutter speeds can be used with them.

I hope I have finally mastered the art of adding photos to my notes, so if I have any kind of luck, the photo below shows the "Vacu" version COOIF on a Leica IIIa --

Regards,
Steve Busch

LeicaCOOIF-VACU.jpg
 
Xayraa33 and Steve,

Thank you for the details !!!

I have to dig into my earlier Leica Manuals and catalogues... I'm pretty sure I have seen a 1930's photo of a Leica with a Leitz "cliip-on" flash sync, with the sync body tailing down over the front of the camera ?

I also like to collect older flash gear... the oldest Leica bit I have is the "blitzlichthalter", from the 1930's, which has a clamp that fits around the end of the camera, then the flash-tube clips-on to that, and the reflector sits on top... the battery tube is black-lacquered brass, and holds two D cells... it is Heav-vy !

have the bracket, the tube, the reflector, the box... the only thing missing is the sync mechanism. I have used it though, with adapters for M-bulbs and a PC>Leitz bi-post cord, on a black III that had PC sync added.
Certainly gets peoples attention ! :eek: :D


As for flash sync speeds, from what I have read in various Leica Manuals and Leica pamphlets, electronic flash can be successfully used only at shutter speeds where the curtain is fully-open across the entire film-gate at the same time (1/20 to 1/30). This is due to the short duration of the strobe flash. Used at higher speeds, the shutter blinds may mask one or both edges of the image.
Then there's the issue of getting the flash to fire at the appropriate moment.

I have read that most Leicas that had their sync added by a third-party are synced at 1/30, and are suitable to use with electronic flash.

If you can find true FP bulbs, they have a long enough duration to use at almost any shutter speed, as long as the flash fires early enough.

I am trying to get one of my 1950's Braun electronic flash-guns going ( the black-plastic with the shoulder-bag battery case), so that I can have electronic flash with vintage look... so far I can't get any of them ( I have five ) to charge off the dry-cells :confused: ... there's a small capacitor in the vibrator circuit that may be the culprit... unfortunately it does not have a value stamped on it, only a Braun part # ... :mad:

If those can't be fixed, at least I have a Honeywell "Futuramic Strobonar" in working order.... ;)
 
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Have a look at my earlier thread, check my photo. Do you think my cam dial was used with the vacu?

http://www.rangefinderforum.com/forums/showthread.php?t=87852

What puzzles me about mine is that I also have a PC socket on the back just below the accessory shoe, this fires an electronic flash. Do you think my speed dial was a left over from when the vacu unit was used and later the camera was modified to have built in sync? In other words it is now redundant.
 
Have a look at my earlier thread, check my photo. Do you think my cam dial was used with the vacu?

http://www.rangefinderforum.com/forums/showthread.php?t=87852

What puzzles me about mine is that I also have a PC socket on the back just below the accessory shoe, this fires an electronic flash. Do you think my speed dial was a left over from when the vacu unit was used and later the camera was modified to have built in sync? In other words it is now redundant.

That seems like a logical explanation.


I have two black III's that have had PC sync added, one through " Leica" on the top plate, the other on the back side near the VF window.

I have not checked them out to see how they are synced...
 
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