|Posted: Mon May 07, 2018 9:36 pm Post subject: Enna Tele-Ennalyt 240/4.5 - Sockel
|Enna Sockel Tele-Ennalyt 240/4.5
I found this on the late lamented Adolph Gasser (the last great San Francisco camera Store) bargain table some years ago.
DSC00785 by luisalegria, on Flickr
This is the famous, or infamous, Enna Sockel mounting system, with the longest lens head supplied for the system, the 240mm f/4.5
It is an example of the second version as this is a fully-automatic mount (this example is for Exakta of course) with manual/auto switch. This is probably from after 1964. The original from the 1950's was semi-automatic and needed to be "cocked" to stop down, like many other "auto" lenses of the period.
The Enna Sockel system is a similar idea to most interchangable mount systems, with the extra twist that the lens mount included not just the mount with camera interface hardware, but the aperture setting ring and focus helical and various other bits as well - the Sockel (socket) is therefore quite a complex piece, unlike a Tamron Adaptall mount or suchlike. The lenses for the Sockel system were therefore rather simple, consisting of just the optics and the aperture mechanism, which bayoneted into the Sockel.
The advantages are of course potentially a cheaper lens set, with just one complex mechanical part (the Sockel), the ability to use the same set of lenses on different makes of camera, and so forth. The 240mm is rather compact and light for what it is, lacking suitably scaled focus mechanisms, etc. I've pictured it on a tiny Exa. And its not actually an overwhelming lens on a tiny mirrorless Nex-7 either. But at a cost, see below.
The system seems to have been sold in fair numbers for the time as these are not really rare, and persisted in production from 1958-67 apparently. I think Enna got out of the lens business shortly after. They are genuine curiosities.
This technical approach has been tried a few times, but I think this was the only case where the focus mount/aperture ring was not integrated in the camera body, as with the Deckel system (Retina Reflex, Voigtlander) or Contax rangefinders.
Problems - well, on mine the Sockel is defective as the aperture mechanism seems to be jammed, and this is a complex piece - thats one clue as to design issues. I therefore set the aperture manually on the lens body (wide open) before putting it into the Sockel. I may get around to working on it, but there is a considerable backlog on my bench! The other problem is that one helical has to serve for all focal lengths, 24mm-240mm, so on the 240mm there is very restricted focus travel, leading to a minimum focus of 20ft/6 meters, which is pretty darn long for 240mm. Therefore I mostly used this thing on a stack of Exakta extension rings. Not the most convenient 240mm lens!
Performance - everything was done wide open, so I can't comment on reasonable apertures. It seems a bit soft wide open I think, and has fairly low contrast. Not out of the ordinary for lenses from its time, but certainly not outstanding. I was not really able to do "the bird" properly within the minimum focus of the lens. Its not bad at all on extension rings.
DSC00805 by luisalegria, on Flickr
DSC04687 by luisalegria, on Flickr
DSC04768 by luisalegria, on Flickr
DSC04799 by luisalegria, on Flickr
DSC04838 by luisalegria, on Flickr
DSC04846 by luisalegria, on Flickr
DSC04854 by luisalegria, on Flickr
DSC04907 by luisalegria, on Flickr
DSC04915 by luisalegria, on Flickr
I like Pentax DSLR's, Exaktas, M42 bodies of all kinds, strange and cheap Japanese lenses, and am dabbling in medium format/Speed Graphic work.