B&L Photomicrographic Apparatus IV: The DynaZoom Camera


It would be lovely to simply write that the DynaZoom camera is compatible with any photomicrographic head of the DynOptic/DynaZoom line and leave it at that. Keen observers however, will note that the same sort of head was employed on a range of B&L microscopes from industrial inspection outfits too metalographs. In some instances there is evidence to suggest that although the head is superficially identical, the internal optics are such that the camera will not be parfocal with the oculars. It is not that some of the following following camera will not function perfectly with compatible microscopes of other lines but that it is near impossible to determine before hand. Know then that for the best results one should employ any of the following with only photomicrographic DynOptic/DynaZoom microscopes. One may immediately identify a suitable microscope of the above mentioned line by the presence of a knob marked “Cam._Vis.” and threaded socket with slotted cap.


The DynOptic/DynaZoom line spanned a significant period of development at B&L, and a proliferation in photographic offerings from an early B&L ally, Eastman Kodak. It should then come as no surprise that there were a number of versions and variations on the basic system. The common features of all were the thread size of the basic mount, the presence of a manual shutter speed setting and a standard mechanical shutter release. None of the camera systems make use of an internal prism or beam splitter, the optics required being housed entirely within the microscope head. This simplification of the apparatus was not unique to B&L but a common aspect of photomicrographic systems that were designed for use with offerings from a single manufacturer rather than any stand.

Versatile models


Note the knurled focus ring above the shutter speed.

The first model of DynaZoom camera was perhaps the most robust of the offerings. Unlike later versions it was the only DynaZoom camera to offer an integrated variable lens system to permit focusing and parfocalizing for each camera back. A focusing lens system, initially considered essential by the opticians at B&L, fell out of favor with the increasing popularity of consumer photography; almost as if there was a desire to bring photomicrography more in line with the rapid point-and-shoot aesthetics of holiday snapshots. Today this feature is a great help to users who may not be able to ensure the optical compatibility of their microscope and a superficially compatible camera system.

Sometime later the DynaZoom camera underwent a significant redesign. Manual focus was removed, and the gender of the camera back mount changed. Previously the DynaZoom camera back used a female mount with the camera system having a male mount. The new version swapped the genders and reduced the available shutter speeds. Other noteworthy changes include the general decrease in size of the apparatus and the integration of optical elements between the mounting threads and shutter; previously all optical elements were located on the camera side of the shutter. It should also be pointed out that fixed length bellows were installed (by flat headed screws) on the new systems. Short bellows of 3x enlargement and long bellows of 10x are known.


Difference in coupler on unrefurbished models.

One may also note the redesign of the threaded coupler. In the more advanced, earlier model the coupler was provided with a male dovetail fitting on the camera side and fixed in position by two 5/100th inch hex set screws. In the smaller versions the coupler was a female dovetail held in place by two flat head set screws. The sturdy male dovetail over which the coupler fits is considerably more developed and with the lower weight of the overall system one is more comfortable leaving the set screws somewhat loose to facilitate ease of installation.

Single format Versions

Where all previously discussed systems were component based, consisting of standard shutter/optical assemblies with various camera backs, the gray series of DynaZoom microscopes saw a further redesign, the introduction of single format camera systems. The Polaroid Land camera roll film system is the only model confirmed as a single format system.

Superficially identical, the shutter system is noteworthy for having a narrower diameter lens system between the shutter and microscope, meaning the threaded coupler is not interchangeable with that of the versatile models. Previously an bellows system with integrated Land camera back was available for all models.


∗Facing the eyepiece(s) the knob will be on the observers right hand side. DynaZoom models will have a zoom knob on the left hand side.

†Systems like the Model N expolored previously or the Mikas by E. Leitz, explored here.

‡Previously one could select 1/100 1/50 1/25 1/10 1/5 1/2 or 1 while now only 1/200 1/100 1/50 1/25 and 1/10 were offered. In each version T and B were always present. It’s not surprising that the slower speeds were eliminated as they were seldom needed with improved lighting and film technology.

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