KMZ Zorki 3S

Zorki 3S

The KMZ Zorki 3S is a Soviet 35mm coupled-rangefinder camera produced in 1955 and 1956. It combines an M39 screw lens mount, a removable rear body section, a combined viewfinder and rangefinder, shutter speeds from 1 second to 1/1000 second, and factory-installed flash synchronization.[1][3]

The camera was developed from the Zorki 3M. KMZ retained the earlier model’s unified shutter-speed control and integrated slow-speed mechanism, then added a flash synchronizer with adjustable ignition timing. The synchronization components required a larger and taller upper housing, creating the basic body shape later used for the Zorki 4.[1][3]

The original Cyrillic name is Зоркий-3С. The final Cyrillic letter С is pronounced and transliterated as “S,” referring to synchronization. Zorki 3C and Zorki-3C are common alternative seller names, but they do not indicate a separate model.

---

History

Development and Production

KMZ introduced the Zorki 3S in 1955 as the synchronized successor to the Zorki 3M. The factory archive describes the change as the addition of flash synchronization together with a redesigned upper cover.[1]

Official production records list 2,921 cameras in 1955 and 42,651 in 1956, giving a total of 45,572 units.[2]

The Zorki 3S had a short production life because its basic design was quickly developed into the Zorki 4. The Zorki 4 retained the shutter, finder, flash system and removable back of the Zorki 3S while adding a mechanical self-timer.[1]

Shutter and Operation

The Zorki 3S uses a horizontal-travel focal-plane shutter with rubberized cloth curtains. Its marked shutter-speed sequence is:

• B
• 1 second
• 1/2 second
• 1/5 second
• 1/10 second
• 1/25 second
• 1/50 second
• 1/100 second
• 1/250 second
• 1/500 second
• 1/1000 second

All speeds are selected with a single control on the upper housing.[3]

The shutter must be cocked before the selected speed is changed. The selector is lifted, rotated to the required marking and lowered into position. It must not be forced across the unmarked interval between 1/25 and 1 second.[3]

The slow-speed mechanism operates at 1 second through 1/10 second. These settings are often affected by hardened lubricant on cameras that have not been serviced.

The B position keeps the shutter open while the release is held down. The shutter-release button can also be locked in the depressed position, providing a time-exposure function comparable to a T or Cyrillic Д setting.[3][4]

Flash Synchronization

The camera has a factory-installed cable flash connection. Its accessory shoe is mechanically passive and does not have an electrical center contact.

A synchronization scale beneath the shutter-speed control adjusts the ignition lead for different flash sources. Electronic flash is used at the zero setting, while flashbulbs can require an advance of up to approximately 25 milliseconds.[3]

Flash photography is officially supported at 1/25 second and B, when the film aperture is completely open. The electrical synchronization contact should be tested separately from the shutter, as the shutter can operate while the flash circuit remains defective.[3]

Viewfinder and Rangefinder

The optical viewfinder and coupled rangefinder are combined in one eyepiece. This allows the photographer to focus and compose without moving between separate viewing windows.

Finder magnification is approximately 1.15×, with a physical rangefinder base of about 38 mm. A lever beneath the rewind control provides diopter adjustment.[4]

The fixed finder field is intended for a lens of approximately 50 mm. It has no projected framelines, selectable frames or automatic parallax correction. Other focal lengths require an external accessory finder fitted to the cold shoe.

Relationship to the Zorki 3M

The Zorki 3M and Zorki 3S share their cast body, removable rear section, combined finder and single-dial shutter mechanism.

The principal difference is factory flash synchronization. A standard Zorki 3M has no flash terminal or synchronization scale. The Zorki 3S has a front cable socket and an adjustable ignition-delay control beneath the shutter-speed selector.[1]

The upper housing of the Zorki 3S is taller and extends farther across the body because it contains the synchronization mechanism.

A Zorki 3M with an aftermarket flash socket should remain identified as a modified Zorki 3M unless it has the complete factory housing and controls of the Zorki 3S.

Relationship to the Zorki 4

The Zorki 4 is closely related to the Zorki 3S and was introduced in 1956. KMZ describes it as a Zorki 3S fitted with a self-timer.[1]

A standard Zorki 3S has no self-timer lever or self-timer release button beside the lens mount. The early Zorki 4 adds these components while retaining a very similar upper housing and control layout.

A camera with missing or removed self-timer parts should not be identified from the lever alone. The model engraving, body openings and front casting should also be examined.

Mount and Lens Compatibility

The Zorki 3S uses an M39 × 1 rangefinder screw mount with the nominal register associated with Soviet rangefinder cameras.

The thread and register concept are comparable to Leica screw mount, and many Leica, Soviet, Japanese and European rangefinder lenses can be physically fitted. However, differences in rangefinder calibration, cam geometry, manufacturing tolerance and previous repair work can cause focusing discrepancies.

Unfamiliar lens and body combinations should be tested at close distances and wide apertures when accurate rangefinder coupling is important.

Lens Kits

The 1956 factory description lists the Jupiter-8 50 mm f/2 and Jupiter-17 50 mm f/2 as standard lenses.[3]

The Jupiter-8 is the lens most commonly encountered with surviving Zorki 3S cameras. Other compatible M39 lenses can be mounted without changing the identity of the body.

The supplied lens should be stored as listing metadata because lens model, optical condition and originality can significantly affect the sale price.

Dimensions and Weight

A measured Zorki 3S body without a lens weighs approximately 590 g.[4]

Published weights can differ depending on whether the lens, take-up spool, film cassette, case or accessories are included. Body-only measurements should therefore be preferred for the main camera specification.

The camera has a removable combined rear and base section. Two rotating locks on the underside release the back, providing direct access to the film chamber and simplifying loading compared with earlier bottom-loading Zorki cameras.[3]

Combined Variants

The short production period resulted in relatively few major variations. These should remain combined under one main Zorki 3S page.[5]

A prototype announced in 1955 has a different style of model marking. The earliest documented regular-production configuration uses an older shutter-release design and can carry additional “Made in USSR” or Cyrillic country-of-origin markings on the rear.[5]

A later production version uses a revised shutter-release button. Collector-documented reference examples include serial number 5505913 for the earlier configuration and 5645085 for the later version.[5]

Most cameras have decorative rims around the front finder windows. A rare late configuration without these raised rims has also been documented.[4]

These differences are suitable for metadata such as exact_variant, production_period, shutter_release_type, finder_window_trim, engraving and export_version.

Serial Number Information

Regular-production Zorki 3S cameras use year-coded serial numbers. The first two digits normally indicate the production year, giving prefixes of 55 and 56.[2][5]

Collector-documented examples include:

• 5505913, early regular-production configuration
• 5632815, 1956 production
• 5645085, later shutter-release configuration

These numbers are reference examples and should not be treated as confirmed factory start or end points. No reliable continuous model-exclusive serial range has been established.

Identification

A standard Zorki 3S has:

• An M39 screw lens mount
• A combined viewfinder and rangefinder
• One rear eyepiece
• Diopter adjustment
• A single shutter-speed selector
• An adjustable flash-delay scale
• A front cable flash socket
• A removable rear and base section
• Permanent strap lugs
• No self-timer

The upper housing is normally marked Зоркий-3С. Sellers may describe the same marking as Zorki 3C because the Cyrillic С resembles a Latin C.

Collector Notes

The shutter should be tested separately at the slow and fast settings. The slow-speed escapement, 1/1000-second setting and flash contact can fail independently.

The cloth curtains should be inspected for pinholes, cracking, wrinkles and uneven travel. Finder haze, a weak rangefinder image, vertical misalignment and a seized diopter control are also common age-related problems.

Removable backs, controls and lenses can be exchanged between cameras. Identification should therefore combine the serial number with the engraving, shutter-release design, finder-window trim and other production characteristics.

For price tracking, useful metadata includes exact_variant, production_period, shutter_release_type, finder_window_trim, engraving, export_version, included_lens, flash_sync_condition, rangefinder_condition, slow_speed_condition, shutter_condition, accessories, case_included and body_only_or_kit.

---

Sources

• [1] ZENITcamera Archive. The Zorki Camera Line. https://www.zenitcamera.com/archive/zorki/index.html
• [2] ZENITcamera. KMZ Camera Production Data. https://www.zenitcamera.com/catalog/cameraproduction.html
• [3] KMZ. Zorki 3-S Description, 1956. https://eugigufo.net/files/photovideo/photo/zorki3c.pdf
• [4] Fototekhnika SSSR. Zorki-3S Camera Review and Instructions. https://fotoussr.ru/cameras/zorki-3s/
• [5] SovietCams Archive. Zorki-3C Classification. https://ussrphoto.com/sovietcams/index7027.html?_m_e_id=25&_menu_i_id=212&tmpl_id=178&tmpl_into=middle