The Pentacon Six System
by TRA

Lens Data Summary


The 400mm Tele-Ennalyt in Praktisix/Pentacon Six mount

Dr W G Heyde’s book “Das Praktisix Buch”, published in 1964, refers to an f/4.5 / 400mm Tele-Ennalyt.  In October 1972 Cambridge Camera Exchange was advertising this lens for US$132.50.  Sam Sherman of New Jersey tells me that “It focuses with a single helix and has reasonable sharpness for a 400MM lens.”

Lens name Max aperture 
& focal length
Type Angle of view 
Closest focus 
Front filter thread
Length incl hood
Max dia
Tele-Ennalyt f/4.5 / 400 Manual Diag: 12°
Horiz: 8°
32 4.75 94mm 289 100 1884


1 Not measured; taken from data for the Norita 400mm lens
2 See more information in description below
3  See more information in description below
4 Length without lens hood: 238mm
5 Weight without lens hood: 1750g

This lens was produced over a number of years with slight variations of cosmetic finish.  This may have resulted in slight variations of weight and dimensions.  I give here the weight of the lens reviewed on this page, with standard lens hood and front lens cap, but no rear cap, as in use on the camera it will not have a rear lens cap.  The imperial weight equivalent is 4lb 2¾ oz.


The first thing that one notices when seeing and handling this lens is the finish.  It consists of an extremely fine-grained mottled effect, which is totally matt, easy to hold and does not show finger-prints.  In consequence of this finish, the colour looks like a mid-tone grey, except for the aperture and focus index rings, which have a shiny black finish.

Focussing ring

The focussing ring is marked in metres and feet.  From infinity to closest focus it rotates through approximately 320°.  Rotation is extremely smooth, although there is a higher degree of resistance than is common with most lenses.  The reason for this will become clear in the next section.

Aperture ring

The aperture ring has click stops at 5.6, 8, 11, 16, 22 and 32.  However, it also moves well beyond the f/32 position.  Tests have revealed the following:

  • click stops for apertures down to f/22 inclusive are accurate.
  • These click stops also correspond to the aperture markings on the aperture ring.
  • The click stop after f/22 occurs when the aperture ring is half way between the f/22 and the f/32 markings on the aperture ring.
  • Checking the value at this click stop position confirms that it is effectively half a stop smaller than f/22 (f/27).
  • Moving the aperture ring to the position where the f/32 marking is aligned with the index mark does indeed result in an aperture of f/32 - but there is no click stop in this position.
  • The aperture ring can be moved a considerable way beyond this position, to the end of its travel.
  • At that position, an exposure reading shows that the aperture has been stopped down by a further two stops after f/32, to an effective aperture of f/64
  • There is, however, no détente (click stop) between f/32 and f/64 (or even at f/32).  A potential détente at the next full f/ stop (which would be f/45) does therefore not exist on the example of the lens that was the subject of this test.

The Tele-Ennalyt with the aperture ring 
at the last click stop (f/27)

The Tele-Ennalyt with the aperture ring
at the end of its travel (f/64)

In fact, most of this is pretty academic.  Tests were carried out with a calibrated prism at an ISO setting of 160/23 (“ASA/DIN”), on a bright sunny day, with part of the image being of a brightly-painted building in the sun, and the rest being clear blue sky, so this was a brighter-than-average scene.  The correct exposure at f/11 required a shutter speed of 1/500 sec.  This is an excellent combination for a lens of this focal length, as for hand-held use one would be advised to use 1/500 as the slowest speed, and f/11 is generally the aperture at which many lenses give their best results.  Choosing smaller apertures for this ISO setting and scene brightness would result in the following combinations:

Shutter speed required
f/27 (½ stop)
1/90 (not available on the P6)
f/32 (no détente)
f/45 (no marking nor détente)
f/64 (end of ring travel)

Of course, if your camera and lens are mounted on a tripod, you can certainly use the smaller apertures, with the appropriate slower speeds.  However, unless the people in the image are also mounted on tripods and the branches of the trees are held fast in giant “plamps” (plant clamps), you are going to see movement in the resultant images.  Naturally, if you are shooting a picture of a series of buildings that are receding into the distance at an angle, you may be delighted to have the option of an aperture as tiny as f/64, in order to increase the depth of field (and you may wish to have moving objects rendered as a blur).

Like the Novoflex lenses, this is manual aperture lens: there is no auto diaphragm stop-down operation, nor even a “pre-set” lock, as is normal with lenses from Meyer-Optik and some other manufacturers; there are détentes at each full stop position (and at f/27), so you just count the clicks to stop down.

The aperture ring and index line are located forward of the focussing ring, and the whole of the forward section of the lens rotates as one focusses, taking the aperture ring and aperture index line with it.  In consequence, when the lens is focussed at certain distances, they are no longer visible from the normal operating position above the lens.  However, Enna have thought of this and have provided a second aperture index line on the barrel and a separate set of aperture values on the aperture ring at 180° from the primary points.  Concretely, at a focussing distance of 7.5 metres the secondary aperture index line is centred on the top of the lens (in line with the focussing index line), with the full set of aperture values visible again.  In practice, at intermediate distances there should be little difficulty in seeing one or other of the aperture index lines and the aperture numbers.

Lens focussed at infinity
The primary aperture index ring is
indicated by the arrow.

Lens focussed at 7.5m
The secondary aperture index ring is
indicated by the arrow.

Lens focussed at closest focus
The primary aperture index ring is
indicated by the arrow
(as it re-appears round the right-hand
edge of the lens).

When turning the aperture ring, one must be careful to prevent the whole of the front section of the barrel from turning slightly, which would change the focus.  In practice, this proves to be easy to achieve, by simply placing a hand under the barrel so that it rests on the palm while one rotates the aperture ring with the forefinger and thumb of the same hand.  The in-built resistance in the focussing mechanism also makes unwanted change of focus improbable.

Fourteen aperture blades produce a totally round iris that reportedly delivers beautiful bokeh (out-of-focus highlights).


In measuring the size for filters I came up with the following dimensions:
Top of filter threads on lens: 93.94mm
Top of filter threads on lens shade 94.94
Since the two threads obviously mesh together, I assume that this is a filter thread diameter of 94mm.  I do not know the pitch of the thread, but for this sort of size one would expect it to be ×1.

However, there is a drawer in a slot near the back of the lens for accommodating much smaller filters.  I have measured the circular hole for the filters, and it has a diameter of 33.15mm, so presumably filters with a diameter of 33mm would fit well, although I have not yet had a chance to check this.  It is obviously essential that this drawer be in place at all times, as otherwise light would get into the lens from the empty slot.  The lens reviewed here was also supplied with a curved piece of plastic that effectively covers the slot, although from a style point of view it seems strange that this is grey in colour.

The empty slot for the filter drawer can be seen in this image.
The filter drawer and the drawer-opening cover
can be seen on the right.

The drawer-opening cover has now been inserted into
the filter drawer slot, and the filter drawer itself
can be seen on the right.

Kilfitt had a similar system, but I have only seen it on their lenses for 35mm cameras, as in the case of their camera mounts for 6×6 cameras there was not generally enough space at the back of their lenses to allow for such a drawer.
Tripod bush

The lens reviewed here has a 3/8” tripod bush to which a 3/8 to 1/4” adapter had been fitted.  The bush is in a small platform that provides good, positive contact with the tripod head, preventing unwanted movement.


The Tele-Ennalyt tripod platform

The tripod bush is mounted on a part of the lens that does not rotate, but by moving a small lever at the back of the lens into a vertical position, one is able to rotate the camera mount in order to level the camera.  Returning the lever to its initial position (approximately horizontal) locks the lens in the desired orientation.

The mount rotation locking lever (arrowed) in unlocked
(vertical) position

The mount rotation locking lever in locked
(approximately horizontal) position

Size & weight

This lens meets the definition for a genuine telephoto lens, i.e., it is physically shorter (and considerably so) than its optical focal length.  This picture provides a comparison of 300mm – 500mm Medium Format lenses in offered by their manufacturers in Pentacon Six mount.

From L to R:
f/4.5 300mm Meyer-Optik Telemegor, a late production f/4 300mm Meyer-Optik (initially called “Orestegor” and then for many years known as “Pentacon”), f/4 300mm Carl Zeiss Jena Sonnar, f/5.6 Heinz Kilfitt Pan-Tele Kilar, f/4.5 300mm Tair-33, f/4.5 400mm Enna Tele-Ennalyt, f/5.6 500mm Arsat APO, f/5.6 500mm Pentacon, f/5.6 500mm Novoflex Tele-Novoflexar

300-500mm lenses, focussed at infinity with front and rear caps off (rear caps not shown) and lens hoods off where possible (the Tair and the Arsat APO have retractable lens hoods that cannot be removed)  There is no lens hood for the old Meyer Telemegor.

In fact, the Tele-Ennalyt is shorter than some 300mm lenses, as can be seen from these two pictures.  It is also lighter than several of them. 

Lenses ranged in the same order as in the previous photograph.
The 400mm Tele-Ennalyt is slightly shorter than the 300mm Tair, which is standing to its left,
and only a little larger than the 300mm Kilfitt Pan-Tele Kilar, which is to the left of the Tair.

The Tele-Ennalyt fills a gap between 300mm and 500mm lenses with the Pentacon Six mount.  In fact, few Medium Format cameras from other manufacturers had a 400mm lens in their line-up.  There had been a 400mm f/5.5 Telemegor from Meyer-Optik, Görlitz, but it appears that this had ceased production by the mid 1960s. (CHK!)  (Norita also theoretically had a 400mm lens, but the 400mm Noritar must have been produced in extremely low quantities and must now be viewed as an extremely rare lens.)

The 400mm Tele-Ennalyt was supplied, at least sometimes, in a shiny light-tan leather case with strap, although the one reviewed here came (second-hand) in a standard GDR case (347mm long × 140mm dia) which is obviously not original, as Enna was a West German company based in Munich.  The lens reviewed here also had a GDR front lens cap.

This lens was also sold re-badged (and not with a Praktisix/Pentacon Six mount) as “Revue”, the brand name used by the West-German firm Foto-Quelle of Nürnberg.


Further pictures + review of performance to follow
[results of tests]

chromatic aberration …
contrast …
vignetting …

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© TRA,  January 2012, revised September 2016