Shift Lenses
The Problem
Here is a shot that I took recently in Berlin. I wanted to frame the ruins of the Kaiser-Wilhelm Gedächtniskirche (Memorial Church) with the broken links of the chain, and also include the skyscraper at the right.
The “falling over buildings ” problem is solved, but another – bigger! – problem has taken its place. Not only have I lost the top of the skyscraper and even the top of the broken chain, I have gained a vast expanse of boring and unwanted foreground.
The Solution
One hundred years ago, this would have not presented a problem; the photographer merely slid upwards the lens board, which moved the lens up, cutting out the unwanted foreground and including the top of the building. But how can one do that with an SLR camera?
When the new company Exakta GmbH announced the Exakta 66 in 1984, one of the top selling points was that it would be a vehicle for the outstanding lenses produced by Joseph Schneider of Bad Kreuznach, the quality of whose lenses was already well established. At the time they were providing zoom lenses for the Hasselblad, and a range of lenses for Rollei and other cameras.
Among the lenses to be offered in the Exakta 66 mount was the Schneider PCS Super-Angulon f/4.5 55mm shift lens.
Users of 5 × 4 inch and larger cameras are used to the freedom of raising the front standard to include the tops of tall buildings without having to tilt the camera up, which would produce the classic “key-stoning” problem, where the building appears to be falling over backwards, with all the vertical lines converging towards the top of the image. (To see another example of key-stoning, click here and scroll to near the bottom of the 250mm section.) With a standard 35mm or Medium Format SLR this is not possible, although a very small number of manufacturers offer one or more shift lenses, which duplicate the effect of a rising (or falling) front. Such shift lenses tend to have a wider than normal angle, as the need for them usually arises in situations where it is not possible to step back far enough to include the whole of the subject without tilting the camera.
The Super-Angulon is well known as an outstanding lens that has been
available for many years in mounts for Rollei SLRs, and also for the Bronica
ETRS. The illustrations in the Exakta 66 literature seem to indicate
that it was indeed produced in the Exakta 66 mount, although the list price
of DM6,890 + sales tax in 1988 must have led to very few of them
being sold! At Photokina in Köln (Colgne, Germany) in 2002 I
handled one of these lenses in the Rollei 6000-System mount. It is
of course beautifully engineered, although it is extremely heavy (1.65
kilograms in Exakta 66 mount, according to Exakta’s literature).
The recommended retail price, this time including German sales tax, was
€8,400 (that’s eight thousand four hundred Euros – enough to pay for
a good nearly new small family car!)
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An unmasked image projected by a lens will be round, with a gradual
fall-off in brightness and definition towards the edges. Lenses and
cameras are designed so that the part of the projected image that
is included within the exposed area (i.e., the image recorded on film)
meets certain criteria as regards sharpness and does not have noticeable
fall-off in light intensity (vignetting).
Of course, in order to cover the film area completely with acceptable sharpness and without vignetting – even when shifted to the maximum extent – any shift lens has to have a much larger image circle than a non-shift lens, and this must increase the diameter of the lens elements and the mount that holds them and with it the weight and the manufacturing cost. |
Given these factors, it is nothing less than amazing that users of Pentacon Six mount cameras have available to them – new! – a range of shift lenses, and at extremely modest prices!
Arsenal in Kiev have produced their own “Arsat” 55mm shift lens, which is reputedly one of the sharpest lenses available in the Pentacon Six mount.
Hartblei in Kiev realised that the image circle projected by the Arsenal
45mm Mir 26 and the 65mm Mir 38 wide-angle lenses is large enough to enable
the optical components to be put in a mount with a shift facility.
They have designed some excellent mounts for these lenses, and also apply
their own outstanding multi-coating to the optical elements. Here
are the details of these three shift lenses:
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Shift |
Shift |
Shift |
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| Focal length |
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| Maximum aperture |
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| Minimum aperture |
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| Elements/groups |
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| Closest focus |
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| Shift distance |
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| Filter thread, mm |
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| Weight, grams |
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Arsenal are now also producing 45mm & 65mm shift lenses, bearing their ARSAT brand name.
The three Arsat shift lenses (L to R: 45mm, 55mm, 65mm)
as illustrated on the Arax website
(not to scale)
All five lenses (45mm from Hartblei and from Arsat, 65mm from Hartblei and Arsat, and 55mm from Arsat only) are in mounts that rotate – so it is possible to shift down as well as up, sideways, or even in other diagonal directions if required.
The Hartblei 45mm and Arsat 55mm lenses offer a maximum shift range of 12mm. However, the Hartblei 45mm lens has the 11 & 12mm shift positions marked in red, which means that with this degree of shift there is likely to be some vignetting on the opposite edge to the shift, and this extreme shift should only be used if the image is to be cropped, or the lens is mounted on a camera with a 6×4.5cm nominal film gate or film back. The Hartblei 65mm lens has a maximum shift range of 10mm, with the 10mm position marked in red for the same reason.
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To give an idea of scale, here is the 55mm Arsat shift lens next to
the 50mm Flektogon. A shift lens will normally be more bulky than
a non-shift lens, because
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Note that it is not practical to build an automatic aperture link into
shift lenses, so all of these lenses have a manual pre-set aperture.
However, for the type of photography for which they are designed, which
is careful and methodical and usually using a tripod, this is not a problem.
The Arsat 55mm shift lens even has an easy-to-use stop down ring (labelled “A” in the image on the left) so that the pre-set aperture can be easily found without taking one’s eye from the viewfinder and it has a cable release socket on the lens (labelled “B”), to provide automatic stopping down of the lens via a double cable release. |
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With a double cable release, pressing one plunger first stops down
the lens and then fires the shutter.
Adjust the timing of the two cables by rotating and locking the rings marked “A” and “B” on the image to the left. I have marked each cable with a paper collar (visible at the far end of each cable) marked “camera” and “lens”, respectively, so that I don't inadvertently connect the cables the wrong way round. |
These shift lenses are available new from Michael Fourman at www.kievcamera.net and from Gevorg Vartanyan at www.araxfoto.com
Never mind the width, what about the quality?
So what is the quality of the images produced by these lenses?
The 45mm and 65mm Hartblei shift lenses
For the non-shifted performance of the 45mm and 65mm lenses, I would refer you to the Wide-Angle lens tests section. Of course, even apart from the shift capabilities, there are some major differences.
The following pictures are not really a fair test: taken late afternoon on a winter’s day, shot into the sun, which is actually within the picture area (!), just behind one of the palm trees, the hot spot on the right is not a lens fault but the lighting at the time. Thus, the fall-off in lighting from this spot is not vignetting. This side of the building was in the shadow, resulting in a lack of contrast and in particular a lack of shadow detail. However, these two pictures do show the relative field of view of the 45mm and 65mm Hartblei shift lenses, both shifted up by 9mm. With a steeply rising pavement, we couldn’t have got a shot of this house without tilting the camera up – if we hadn’t had a shift lens! In spite of the adverse circumstances, we did get two shots with virtually no vertical keystoning, and no vignetting!
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The lamp post on the left in the 45mm picture reveals some barrel distortion, though I may have had the camera slightly tilted up, which makes it appear worse (no tripod and no spirit level used – I wanted to get the picture taken before the owner came out and asked me what I was up to!) By the way, the tree stump just left of centre is twisted – that’s not a distortion introduced by the lens!
Finally, here is that problem Berlin view again, this time using the
45mm Hartblei Super-Rotator with the full 12mm shift. I'm repeating
the other two shots beside it, to enable you to make easy comparisons.
All shots taken from exactly the same position, with a Pentacon Six TL
at 1/250 f/9.5 with Fuji NPH 400.
Hartblei 45mm Super-Rotator Zero shift. Camera body tilted up |
Hartblei 45mm Super-Rotator 12mm shift up Camera body held upright (parallel to subject) |
Hartblei 45mm Super-Rotator Zero shift. Camera body held upright (parallel to subject) |
In my opinion, the results really are excellent.
The 55mm Arsat shift lens
Here are two comparison shots taken with seconds of each other from
the same spot with the 55mm Arsat shift lens, both with the Pentacon Six
at 1/250 f/14 on Fuji NPH 400 negative film
Zero shift, but camera tilted up |
Lens fully shifted up (12mm) Camera (virtually) horizontal |
This looks like a truly great lens. Straight lines right to the edges, no discernable vignetting, even at maximum shift, and virtually no visible chromatic aberrations even with enormous enlargements. An ideal shift lens for the Pentacon Six – and coincidentally with the same focal length as the hyper-rare and hyper-expensive Schneider PCS Super-Angulon f/4.5 55mm shift lens!
To see more advantages of shift lenses, continue to the
Next section (Other advantages of shift lenses)
To go back to the section on Other Accessories, click here.
To go back to the beginning of the lens tests, click below and then
choose the focal length that you want to read about.
Back to beginning of lens tests
© TRA December 2005, August 2007