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Contax G Lenses and Accessories
However, the G system does include a limited but well-conceived range of lenses and accessories that can help make the camera more flexible. Although this list doesn't include every possible accessory, I've tried to list and describe the ones most likely to be of interest to G users. Although I (obviously) don't own every accessory listed here, I've also tried to include notes and tips wherever possible, based on my own experience, reports from other users, or published specifications. -- J.W. Index to Categories:
Accessories included with G1 or G2 camera body:
Lenses: General NotesFor serious photographers, one of the biggest attractions of the Contax G system is the range of Carl Zeiss lenses offered for it. Based on classic optical designs, but newly formulated for the G series, they take advantage of the latest advances in optical computation and glass technology, plus the inherent advantages of the shallow body made possible by the G's non-SLR design. The result is arguably the best across-the-board performance of any 35mm camera lens line. Would-be Contax G buyers should keep in mind, though, that the G lens line concentrates on quality at the expense of quantity and versatility. Currently the lineup includes only six carefully-chosen lenses of rather conservative specifications -- there are no super-speed lenses, no zooms, no macro capability, nothing longer than 90mm. And of course there are no budget-priced alternatives from independent lens makers! (although the Contax lenses are considerably less expensive than their equivalents from Leica, for example.) If you like a zoom lens for travel, or want frame-filling close-ups of flowers, or need an f/1.4 lens for available-darkness shooting... the Contax G lens system just doesn't have it. What lenses the system does have, though, are about as fine as 35mm photography gets. Each one I've used has been an absolutely stellar performer in its category: you'd be unlikely ever to find anything significantly better, and lucky if you can find something else that's as good! The Contax Lens Mount: Contax G lenses all use the unique G lens mount. This is a breech-lock mount: machined flats on the lens and body flanges position the lens at the exact depth required, while a separate locking ring engages lugs to hold the lens in place. The theoretical advantage of this system compared to the usual bayonet mount is that there is no sliding friction between the lens and body flanges, so mount accuracy is supposed to be better over time. A practical advantage with an autofocus camera is that since the lens flange doesn't rotate with respect to the body flange, there is no need to disengage the autofocus coupler when mounting or dismounting lenses. The Contax breech-lock mount does not have a separate locking ring; instead, rotating the outer barrel of the lens by its knurled grip ring secures the lens in place. It's similar to the system used on Canon's FD-n lenses, although less complex because fewer mechanical linkages are involved. However, some photographers unaccustomed to this type of breech lock try to handle it like a conventional bayonet mount, and attempt to remove a lens by twisting the entire barrel (rather than just the knurled grip ring.) Although the Contax has a protective steel pin to restrain the lens against being twisted, it's possible to damage a lens or camera body this way. Just follow the instructions and remember to turn the knurled grip ring -- not the entire lens barrel -- and everything will be fine. Another consequence of this breech-mount construction is that when the lens is not mounted on a camera body, the aperture ring does not turn through its normal range. This does not mean there's anything wrong with the lens -- only that the inner and outer barrels are in different relative positions. Once the lens is mounted on a camera, the aperture ring will work normally. Focusing Rings: Except for the scale-focusing 16mm Hologon, all Contax G lenses focus via the camera body control, so they do not include a separate focusing ring. Who Makes Them: The Contax G lenses, as their instruction manuals state, are "manufactured by the Carl Zeiss Foundation of Germany in Japan." Kyocera, the manufacturer of the Contax camera body, produces the lenses for Carl Zeiss. What Does "T*" Mean? In the descriptions below, you'll see "T*" in each lens name. This designation simply means that the lens is multicoated using the Carl Zeiss Foundation's proprietary T* (T-star) coating process.
Lenses: Wide AngleWide-angle lenses have always been a strong suit of the non-SLR 35mm camera. Super-wides can be hard to focus accurately on an SLR (either visually or by autofocus) because their small image size and great depth of field make it hard to judge sharpness. But the rangefinder focusing system of a non-SLR doesn't "see" through the lens, so it can offer the same level of accuracy no matter what lens is being used. In addition to being easier to focus, super-wide lenses for non-SLRs are easier to design. Wide angle lenses by their nature need a short distance between the optical center of the lens and the camera's film plane -- the "21mm" in a 21mm lens, for example, means that the optical center must be 21mm from the film. Since a non-SLR has no moving mirror, the designer can achieve this by using "deep-set" construction, in which the rear elements of the lens protrude far into the camera body. To clear the mirror of an SLR, though, the designer must use a more complicated optical design with more refractive elements, to position the optical center of the lens far rearward of its physical bulk. The difficulty of doing this meant that the first production super-wide lens -- the 21mm f/4.5 Zeiss Biogon of 1954 -- appeared not for SLRs, but for rangefinder cameras: the Zeiss-Ikon Contax IIa and IIIa models. It wasn't until well into the 1960s that designers worked out the techniques needed to get similar focal lengths to work on an SLR camera while still allowing for reflex viewing. (Older superwides for SLRs required that the user lock up the mirror before mounting the lens, and view through a separate optical finder -- just as he or she would with a rangefinder camera!) The design of SLR wide-angles has been highly evolved over the years, and today's examples can offer very fine performance. But the problem of focusing accuracy remains, even with autofocus systems. And SLR wide angles still unavoidably require complex optical designs with many glass elements (which can raise the risk of reduced contrast and assembly errors.) The Contax G, on the other hand -- with its non-SLR design -- inherits the wide-angle advantages of traditional rangefinder 35s. Its shallow body (only 29mm from lens flange to film, compared to 45mm or more on many SLRs) means it can use "deep-set" designs that allow equal or better performance with fewer lens elements. The 16mm Hologon, for example, needs only five lens elements, while superwide SLR lenses of the same focal length may have 10 elements or more. 16mm f/8 Carl Zeiss Hologon T*
Notes: The Hologon's basic design, by Dr. Erhard Glatzel, uses a nearly symmetrical formation of thick, deeply-curved lens elements. Its fixed aperture and optically simple construction provide high contrast and almost complete freedom from linear distortion. Some light falloff is inevitable with such a wide-angle lens because the corners of the film are considerably farther away than the center; accordingly, a graduated correction filter is supplied to even out exposure when necessary. This filter absorbs an additional 2 stops. Since TTL metering does not work with the Hologon, this factor must be entered on the camera's compensation dial. The Hologon does not work with the G's autofocus system; it is focused by scale (hardly a handicap considering the depth of field available with a 16mm f/8 lens!) Also, the lens' deep protrusion into the camera body causes it to block the TTL meter sensor's "view" of the film plane, making TTL metering impossible. To handle this, the G cameras have a separate external meter cell (covering an angle of about 70 degrees) which is automatically engaged when the Hologon is mounted. The Hologon's depth also prevents TTL flash metering from operating; in the unlikely event you want to use flash with it (where would you get a flash unit that covers 106 degrees?) you'll have to set your exposure manually. Note that despite its enormous angle of view, the Hologon's deepset construction means it protrudes only 11mm from the camera body when mounted -- making the Contax G almost a "pocket camera"! The GF16 viewfinder does not provide parallax compensation, so when shooting close-ups you'd need to allow some leeway to make sure the main subject is completely within the picture area -- although with a 106-degree angle of view, the problem is more likely to be keeping UNwanted "subjects" -- such as the photographer's knuckles and feet -- OUT of the picture area!
Notes: The basic, almost symmetrical optical design of this lens appears to be an update of Bertele's groundbreaking 21mm f/4.5 Biogon of 1954. Its quoted distortion figure is impressively low for a super-wide-angle lens at only -0.5%. The 21mm Biogon offers compact size, wide coverage, and more flexibility than the 16mm f/8 Hologon, at substantially lower cost. Unlike the Hologon, it autofocuses normally and doesn't interfere with the G's TTL metering and dedicated flash systems, and its f/2.8 maximum aperture makes it more suitable than the Hologon for indoor use. The supplied GF21 viewfinder lacks the bubble level found in the Hologon viewfinder, but does include a crosshair as a center-point reference. The GF21 viewfinder does not provide parallax compensation, so you need to allow a little extra leeway around the subject when shooting close-ups. Incidentally, many a user of older rangefinder cameras has cursed the inconvenience of having to focus through the camera rangefinder, then shift the eye to a separate optical finder for viewing. The instructions for the 21mm Biogon recommend that you follow this same procedure: autofocus by aiming through the camera viewfinder, then shift your eye to the accessory GF21 finder for composition. But for non-critical work, you can probably get away with keeping your eye at the GF21, using the central crosshair as a reference point for aiming the AF system.
Notes: Another modern recomputation of a classic Bertele design, the 28mm Biogon is almost completely symmetrical in construction. Carl Zeiss says this lens has lower distortion than Zeiss's highly-regarded Distagon wide-angle lenses for SLRs.
Notes: This compact, reasonably fast, high-performance "wide normal" lens should become a favorite with journalistic and documentary photographers. Its construction is essentially a symmetrical double-Gauss design like that used for the 45mm f/2, with an additional corrective element next to the diaphragm stop.
Lenses: NormalOften disregarded by photographers addicted to superwides and tele zooms, the normal lens is nevertheless an ideal "people lens": well suited for casual head-to-waist portraits (with the camera held vertically), close-ups of group activities, and indoor action shots. Its focal length is long enough to avoid wide-angle distortion, yet short enough that the photographer can interact with subjects and situations. 45mm f/2.0 Carl Zeiss Planar T*
Notes: A classical double-Gauss design, the 45mm Planar offers the flexibility and natural perspective of a "normal" lens with a bit more compactness than could be achieved with the traditional 50mm focal length.
Lenses: Long FocusA medium tele lens rounds out the classic "holy trinity" of focal lengths favored by documentary photographers (typical outfit: 28mm or 35mm lens for "establishing shots," a normal lens for general coverage, and a lens of 90mm or so for dramatic close-ups.) Often called a "portrait lens," the medium telephoto's slightly flattened but natural-looking perspective makes it perfect for head-and-shoulder portraiture and full-length figure studies. For documentary shooting, it has enough "reach" for medium-distance candids, and focuses close enough to provide dramatic tight shots. 90mm f/2.8 Carl Zeiss Sonnar T*
Notes: Bertele's basic Sonnar design provided some of the finest lenses of the '30s to '50s, and continued progress in glasses and design techniques has brought it today to a high level of refinement. Its deceptively simple five-element composition provides light weight, reasonably compact size, low flare, and superb detail contrast. In fact, the Contax G's 90mm Sonnar was cited by 'Popular Photography' magazine in 1994 as the sharpest medium tele lens the magazine had ever tested. G1 Problems: Fact or Fiction? A bit of persistent hearsay on the Internet claims that the Contax G1 has a "design defect" that causes "severe focusing problems" when using the 90mm lens. My own extensive experience with this camera and lens has convinced me that this claim is simply bogus. However, because of the inherent limitations of short-base rangefinders in general, it pays to be prudent when using the 90mm lens on a G1 for critical close-up shooting at full aperture. For more details and practical tips, click here.
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TLA360 |
TLA280 |
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Guide # (ISO 100 in meters, 35mm zoom setting) |
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Flash modes |
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Bounce angle |
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Power |
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Contax offers a range of TLA system accessories that allow multiple, off-camera, TTL-metered flash use. These include:
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TLA Extension Cord 100 |
Simple 1m extension cable with camera "foot" on one end and flash "shoe" on the other. Used alone to move flash off camera. |
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TLA Extension Cord 100S |
Camera "foot" on one end, Contax multi-conductor plug on the other. Used to connect camera to other TLA cable accessories. |
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TLA Extension Connector S |
Flash shoe with Contax multi-conductor socket on a short pigtail cable. Used for connecting flash to TLA cable accessories. Has a tripod socket for mounting. |
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TLA Extension Cords 100SS and 300SS |
1-meter and 3-meter extension cords that connect between the Extension Cord 100S and Extension Connector S. |
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TLA Multi Connector S |
"Splitter" that allows connection of camera to two flash units, or more via daisy-chaining. |
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TLA Attachment Adapter |
Simple tripod-threaded flash shoe for mounting TLA units that have their own accessory connectors. |
External Power Supply
Two optional accessories work together to keep the G cameras going when the going gets cold:
The GP-1 adapter screws into the G's battery compartment, replacing its normal complement of two CR2 lithium batteries. A socket on the bottom of the GP-1 connects it to the cord of the P-8 pack, which holds four AA-size batteries. The long cord lets the photographer keep the pack in an inner pocket so the batteries stay warm. The GP-1/P-8 combo also provides peace of mind for traveling photographers who worry about running out of power in places where the still fairly uncommon CR2 batteries are unavailable.
Camera Cases
Contax supplies several variants of ever-ready case for various combinations of camera bodies and accessories:
For the G1:
For the G2:
Various larger leather-clad "Contax system cases" have also been offered from time to time, although of course you can use any type of camera case to carry your G camera and accessories.
When the Contax G2 was announced, two new lenses were announced along with it: the 21mm f/2.8 Biogon and the 35mm f/2 Planar.
However -- much to the consternation of Contax G1 owners -- it was also announced that the two new lenses would not work on the G1 unless the camera is modified. This announcement has caused some negative comment on Internet photography groups.
In fact, though, the modification requirement isn't as bad as it sounds. Here's why:
Here's the entire policy, taken word for word from the voucher:
CONTAX G1 MODIFICATION VOUCHER ATTENTION: This is an important notice for Contax G1 owners.
The Biogon 21mm f2.8 and Planar 35mm f2.0 lenses were designed after the introduction of the Contax G1. A different technique is used to pass vital exposure and focusing information to the camera body than in the past.
Your G1 must be modified to use these new lenses. To have your G1 modified FREE OF CHARGE, please send it, along with this VOUCHER to the appropriate address listed below. We hope that this necessary modification is of minimal inconvenience to you and that you will enjoy the results from your new lens.
If your G1 was recently purchased, please check the sticker located inside the film chamber, if it is green in color the camera has already been modified at the factory for use with the new lenses. You do not have to send your camera to Contax for modification.
We thank you for your purchase of Contax products.
For additional clarification: the "sticker" mentioned in the notice is the loading-instructions sticker in the film-supply chamber. On pre-modification cameras, this sticker is silver. Late-production G1s that have already been modified by the factory to work with the new lenses have a green sticker, as do all G2 cameras.
(Hmmm... I wonder if non-modified G1s will eventually become collector's items -- as in the case of "non-standardized" pre-1931 Leica C cameras, whose owners passed on having their lens mounts updated when Leitz standardized the dimensions of the Leica screw lens mount in 1931. Oh, well, I'm certainly not going to pass up having my G1 modified on the basis of such a speculative idea!)
Incidentally, if you mount a 21mm or 35mm lens on a non-modified G1, the lens can't be focused, either automatically or by the manual-focus dial. Of course, a non-focusing lens isn't of much use -- but at least no damage occurs to either the camera or lens!
There's a persistent Internet rumor claiming that the G1 camera body has "severe focusing problems" when using the 90mm f/2.8 lens. In my experience, this simply is not true (and I suspect that claims about tests by "a French photo magazine" uncovering "gross focusing inaccuracies" are either simply hearsay or were the result of testing an early-production, out-of-spec camera or lens.) My own experience, based on extensive use of a G1 and 90mm lens, is that there is absolutely no problem throughout most of the lens' performance envelope.
However, the gossip led me to conduct some formal tests, in which I did find one area where caution is needed. When using the 90mm lens on a G1 at full aperture (f/2.8) AND its closest focusing distance (1 meter) -- and ONLY under these specific conditions -- I found a somewhat increased risk (about 1 in 3) of small focusing errors. These errors wouldn't be significant in many situations, but could be noticeable in critical shooting: in a portrait, for example, you might find the point of sharpest focus was on the far eye when you wanted it on the near eye, or vice-versa.
This problem doesn't indicate any design defect in the G1 -- it's simply a consequence of using a fast medium tele lens at close range on a camera with a short-base rangefinder. The Leica CL, to name one example, had exactly the same problem, and the manufacturer warned 90mm lens users to stop down to f/4 or smaller when shooting at close ranges. (For that matter, an autofocus SLR's phase-detection AF system is essentially a short-base rangefinder -- and if you test your AF SLR's performance critically under the same conditions, you may be surprised to find that it isn't perfect either!)
Likewise, you can eliminate the risk of focusing problems with the G1/90mm lens combo when doing critical shooting at 1 meter simply by stopping the lens down to f/4. Or, back up a bit -- moving back to 1.2 meters increases your "margin of safety" without changing the picture much. Or, focus the lens manually via the in-finder focus assist indicators: Popular Photography found that manual focusing improves close-range accuracy, even though it uses exactly the same AF sensors and lens-drive system as autofocus. (My guess is that the focusing CPU is programmed to emphasize to accuracy in manual-focus mode, while aiming for a balance between accuracy and speed in autofocus mode.)
The G2, with a longer internal base length in its autofocus system, should be immune from even this limited problem. I haven't repeated my formal evaluations with the G2, but my informal field testing has convinced me that I don't need to worry about its focusing accuracy with the 90mm lens even when shooting close-ups at full aperture.