Wednesday, March 21, 2012


A little known accessory for Leica screw mount cameras is the VACU.  It was made in a variety of versions.  It offered the use of flash equipment with Leica cameras up to the Leica IIIc.  Its replacement, the Leica IIIf was the first model with built-in flash synch.

Leitz made several versions, all with their own catalog designation. Ranging from CAVOO-A to CAVOO-F.
The CAVOO-A was to be used with the Leica III, the CAVOO-B was for the Leica IIIa and IIIb and several versions for the "c" model Leicas, from CAVOO-C to CAVOO-F.

The unit consisted of a small trigger device that screwed onto the shutter release of the camera.  It worked in conjunction of a small cam that attached to the shutter release dial.  When releasing the shutter, the rotating shutter speed dial would activate a small switch via the cam to fire the flash.  This in turn was connected to the VACU via a short cord with a PC fitting.

Leitz Vacu

The cam attachment came in four different versions depending what model Leica it was for.  A word of caution; I have seen versions of the VACU offered for sale from time to time, but in each case the cam was missing, therefore rendering the unit incomplete and useless.

Cam attached to shutter speed dial

Trigger Switch

The position of the cam on the shutter speed dial is critical because it determines the position of the shutter curtains at the moment the flash is triggered.  Rotating it back or forth will allow for exact positioning.

That, of course, requires a means to see if the flash is fired at the correct moment.  For this there is a very simple solution as explained in the article “TESTING LEICA SM CAMERAS FOR PROPER FLASH SYNCH” from March 8, 2012 on this blog.

VACU on Leica III  Front View

VACU on Leica III  Rear View

The first Leica I ever owned, a Leica III, was equipped with a VACU.  I still consider it one of my prized possessions and I fondly remember leaning to take pictures with this camera, including flash pictures.  It is a great camera to learn with because everything is manual.  It created useful habits that I still practice today.  For instance, after getting many severely blurred pictures, in spite of careful focusing, I learned that it is advisable to pull out the collapsible Summar f/2 before shooting.

Leica III with VACU

But that is ultimately a different story.  I don’t use the Leica III very often anymore in these days of digital photography.  But it does take up a prominent spot in my Leica collection, together with the VACU attachment in place on the camera.

1 comment:

  1. The Leica and cameras and photography in general certainly offer a lot of topics for discussion. But we must not forget the ultimate purpose of why we have cameras; to take pictures. For that reason I would like to start a weekly (or possibly daily) gallery of photographs. But I don’t want this to be a showcase for just my own work; to the contrary, I would like to encourage everyone to submit photographs for display on this blog. The copyright to the photographs will remain with the photographer and no pictures will ever be used for any other purpose unless permission is given by the copyright holder.
    No registration for this site is necessary. Just email any of the photographs to either of my email addresses at: or

    If possible, please include the make and model of the camera (any camera, not just Leica) and any other information you deem important.

    It is my hope that this may become one of the most sought after topics of this blog.

    Thank you,

    Heinz Richter