Ihagee/Exakta/Topcon bellows

At one time or another during the 20th century, all major system camera brands marketed their own macrophotography bellows. In several cases, multiple models succeeded each other within each brand. Third-party macro bellows, of much varying quality and usefulness, were also common for major types of SLR camera mounts. This page discusses a type of legacy bellows, typically branded Ihagee, Exakta or Topcon, from the 1950s and 1960s. These bellows are unusually rigid when locked, and their front and rear standards glide on metal-against-metal surfaces along a prismatic rail of solid metal. More modern bellows frequently use nylon bearings to make movement smoother, with the result that a secure locking is difficult or impossible, and creep, sagging and vibration remain common problems. The nylon inserts may also crack with age, and in extreme cases cause the lens or camera standard to fall off during use.

Many brands and models of bellows use one or two cylindric pipes or rods of metal as guides for one or both standards. I am not a fan of this type of bellows, which I often find to have too coarse tolerances of the sliding parts. This is especially true of extruded (rather than machined) aluminium rails. For example, a few models of bellows branded Exakta and Topcon, frequently seen on the second-hand market, have two cylindrical guides for the standards. These models are not discussed here.

As far as I know, none of the camera brands that used to include bellows in their SLR/DSLR macro system do so at present. With the exception of very expensive bellows by Novoflex (in my opinion, well made but not worth the money), third-party bellows are now cheaply made in China and their quality is just basic. Thus, macrophotographers are forced to look among legacy models to find truly stiff, versatile and user-friendly bellows. Nikon and Olympus OM bellows are good examples I am familiar with, but their standards ride against the rail on nylon inserts, which tend to sag and creep a little under load. Therefore, for some uses, I prefer to have more rigid bellows, like the ones discussed on this page.

The most versatile bellows have moving front and rear standards, as well as a geared platform (usually underneath the rail) that moves the standards and rail as a single unit. The purpose of this geared platform is to allow focusing without changing magnification. Focusing by moving the rear standard only, or the front standard only, does change the magnification, and should generally be avoided. Changes in distance between the standards should only be used for intentional changes in magnification, instead of focusing.

As an alternative, focusing can be done by moving the subject relative to the bellows. This, however, may change the illumination of the subject if the light sources do not move with the subject.

Even the best camera bellows may seize or move too coarsely while focusing, especially when mounted vertically. For this reason, most serious macrophotographers use modified microscope focusing racks, microscope stands and/or industrial linear stages to smoothly and precisely focus their macrophotography equipment, at least in the studio. Some even use modified industrial microscopes salvaged from mechanical shops or the semiconductor industry.

A few legacy photomacrography stands, mostly made by Leitz, Nikon and Olympus, are occasionally available on the second-hand market, but are generally expensive. It often takes years to assemble a working set of accessories through the separate purchase of parts from multiple sources. Some of these legacy systems are optimized for large formats, no longer relevant to digital photography.

Although industrial microscope objectives designed for infinity-corrected optical systems are already popular among advanced macrophotographers, there is still an abundance of finite optical lenses and microscope objectives on the market, and consequently a niche for reliable bellows that lock solidly when needed, minimize vibrations, and allow precise movement of the standards when the magnification needs to be changed. Changing magnification with bellows remains much faster than with a set of fixed extension tubes. Three or four extension tubes of variable length were made in the past, among which the Olympus Telescopic Auto Tube 65-116mm is the only serious contender as a replacement for bellows. Variable-length helicoids are currently available from China in a good variety of mounts, but their extension range is far shorter than bellows, and they do not have a locking mechanism or built-in extension scale.

These bellows are typically coated in light-blue hammered paint, but some specimens are dark gray/black or white (the latter were apparently a part of the Ihagee Kolpofot medical equipment series marketed in the 1950s).

Model 1

Two superficially similar models of these bellows were made. The earlier one (Figure 1-2), called model 1 in the present discussion, has standards cast in solid metal alloy, with a thumbscrew clamping the two sides of the rail mount together against the rail to lock the standards. The thumbscrew is prevented from completely unscrewing by a threaded pin nearby. Each standard has a long and wide slot along its middle. This slot is critical in allowing the metal of the standard to flex, thus allowing the two sides of the standard to clamp against the rail.

According to photobutmore.de, a larger number of models was produced, than the two discussed on this page. According to this source, it seems that three early models with slotted standards were produced, with a number of differences in their details. Based on these differences, Figure 1 should be a third variant of the first model, produced between 1961 and approximately 1969. I do not discuss these variants here, because they are virtually identical with respect to the practical use of these bellows.

This model is almost exclusively available in Exakta front and rear mounts. The front mount is fixed, while the rear mount rotates by 90° (quite stiffly in my specimen) and lacks a locking mechanism to prevent rotation. In some specimens, a thumbscrew on the right side of the rear standard locks the mount and prevents its rotation. There is no such knob in the specimen in Figure 1. Also, sometimes the rear standard carries the brand name, albeit not the specimen in Figure 1.

Some specimens, including the one pictured above, may have standards pressing way too hard against the rail, even when unlocked. In these cases, make sure first that the problem is not dried grease on the rail, by cleaning the rail and the mating surfaces of the standards with denaturated alcohol and a cloth. If the standards are still too tight, they must be separated from the rail, the blocking pins and thumbscrews removed, and the standard halves slightly pried apart from each other by leverage with a strong slot screwdriver inserted in the center slot of the standard. Use care not to to excessively force the standard, which may break. An increase in width of a fraction of a mm can be enough to solve the problem.

Model 2

A subsequent model (Figures 3-4), called model 2 in this discussion, has hollow standards and is therefore much lighter. The rail is the same as in model 1, but the moving platform underneath the rail (not shown) is hollow and lightweight. Although this model is generally available in Exakta mount, specimens with front and rear M42 mounts are also available. This mount is far more versatile than the now obsolete Exakta. The specimen in Figures 3-4 was marketed under the Topcon brand name (visible on the box and in the literature, but not on the item itself).

The Exakta set of lenses and accessories was extremely broad, and probably is still today the broadest in the camera industry. In addition, the Exakta system was also the earliest large system of accessories. In a way, it is a pity that it had some - in retrospect - obvious limitations, including the narrow lens attachment.

The lens mount of model 2 in M42 is fixed. The rear mount, instead, can rotate once the thumbscrew at the bottom left of the standard (as seen from behind) is unlocked. Completely unscrewing the thumbscrew does not allow the rear mount to separate from the standard, so there is no risk of the camera body falling off from the bellows. The broad flange of the M42 rear mount is used to rotate this mount. It is so wide (over 72 mm) that it may prevent mounting some M42 SLR bodies (or DSLRs with other mounts when using a short M42 adapter). Mirrorless bodies do not have this problem if used with a sufficiently long M42 adapter.

Shared features and differences between models

The rear Exakta mount is quite narrow (33.3 mm internal diameter, which is quite less than the 43.3 mm diagonal of a full-frame sensor). This can cause vignetting on full-frame sensors with medium to long bellows extension. The M42 rear mount, on the other hand, typically has a 39 mm internal diameter and is shorter than the Exakta mount, lessening this problem.

In model 2, the machined metal knobs of model 1 (on both standards and rail) were replaced with simpler but more comfortable bakelite knobs.

The clamps of model 2 are less strong than in model 1, but the difference is not great. As a whole, also model 2 is stiff and fully usable. It is important to remember that the locking mechanisms of the two models work in different ways. The locking mechanism of model 2 consists of a pin pressed against one side of the rail, and is more likely to be damaged, or to leave permanent marks on the rail, if overtightened.

The standards of the model 2 are far more fragile than the older ones, and the procedure described above to repair standards of the model 1 that are excessively tight should not be attempted on model 2.

At least in my specimens, the pleated bellows in model 1 are a few cm longer than in model 2. The most likely explanation is that the latter specimen at some point was repaired by shortening the pleated material to eliminate a torn or otherwise defective section. In fact, pictures of model 2 bellows on photobutmore.de show about four more pleats than on the specimen in my possession, which is consistent with the specimen of model 1 discussed above.

The front standard of model 1 has a coarsely machined depression and two small screws on its right side, used to attach a bracket carrying additional accessories, perhaps specific to the Kolpofot equipment.

In both models, the platform under the rail is geared, but does not glide smoothly when the bellows are mounted vertically. The rack is integral with the rail, and not precise enough to work satisfactorily as a focuser. One of the two knobs advances the platform by rotating the gear wheel. The other knob, on the opposite side of the platform, is used to lock the platform against the rail. A third, smaller knob is used to lock the slide and film copier (originally sold as a separate accessory) to the bellows.

A small thumbscrew at either end of the rail prevents the standards from falling off when unlocked. At least in model 1, the head of one of the two thumbscrews is partly machined away, to allow separating the standards from the rail without completely removing the thumbscrew. One or both thumbscrews are often missing in second-hand items.

The standards are sometimes sold mounted on a short rail, perhaps used to keep the two standards together when not mounted on the normal rail.

The standards are not geared, and once unlocked they must be moved to the desired position by sliding them against the rail. When unlocked, the standards of both models may seize agains the rail, or slide unevenly, or "fall" along the rail if the bellows are mounted in a vertical orientation. Since the positions of the standards are supposed to be changed only when magnification needs to be changed, this is not a major problem.

A chrome-plated rod is mounted on the base of the rear standard in model 1. It enters a corresponding socket in the front standard, where it can be locked with a thumbscrew. The purpose is probably to join the two standards when they were stored separate from the rail (Figure 2). Model 2 does not have this rod-and-socket mechanism. The two standards, in both models, were packaged (and optionally sold) separately from the rail.

The rail is slightly too long to prevent the flexible bellows material from stretching dangerously at full bellows extension, especially since this material has often dried out with age and can be somewhat fragile. In fact, the state of the bellows material is an important factor in choosing a specimen of these bellows.

The rail, standards and base are interchangeable between model 1 and model 2.

A number of accessories was originally available for both bellows models, including a pole mount for the base, a film/slide copier, and a type of lens hood (probably used together with the film copier) that screws into the front of the lens standard. The film copier was additionally equipped with a broad rectangular shield of metal sheet to protect the operator from excessive light when the film copier was pointed toward a strong light source.

Large format cameras use a shutter placed in or near the lens, and are therefore very vulnerable to light leaks anywhere behind this shutter, including leaks through the bellows material. Absolutely light-tight bellows are instead not indispensable in a DSLR or mirrorless camera, since their shutter protects the sensor from light leaking through the bellows except during the actual exposure. Nonetheless, significant light leaks in the bellows materials should still be avoided with these cameras, because leaks have the potential of lowering image contrast.

It is often possible to repair very small holes or cracks in the bellows material with black silicone. Use as little silicone as possible in a layer as thin as possible, e.g. applied to the interior of the bellows as a very small dab with the point of a toothpick, then leave it to dry overnight without folding the bellows. Larger cracks can be patched with a black piece of thin cloth glued to the bellows with a flexible textile glue, preferably on the inside of the bellows.

The price of no-brand bellows made in China is so low that they can be used as a source of repair materials for legacy bellows. The bellows discussed on this page are of a fairly average size and folded in the usual square profile, so it is in principle possible to replace the original pleated material as a whole. Four screws, accessible from inside the bellows, are used to fasten the pleated bellows material to each standard. When replacing the pleated material with one salvaged from third-party bellows, it may be necessary to drill and tap four new screw holes in each standard.

Resources

Das Ihagee Kolpofot (in German, 1959). User guide for the Ihagee Kolpofot medical equipment, which centers on a version of the Ihagee bellows.

Summary

The two models of Ihagee/Exakta/Topcon bellows described on this page can be a good alternative when more recent types of bellows are not stiff enough, or when the bellows standards must be locked without any risk of creep. Specimens with M42 mounts are easier to adapt and less likely to vignette than the more common ones in Exakta mounts.