Bronica Medium Format Cameras
By Danny Gonzalez (

"This overview is unique in that it is entirely verbatim, quoted  information, directly from the Bronica Website. The three issues covered  here are the histories of the Bronica ETR and SQ systems and a factory account of  battery compatibility information for each version of these cameras up to the current models.

I'm presenting this information in unedited form to balance the Overview series and because of my lack of experience with the most current Bronica systems. Please be aware that the superlatives employed within the post are not mine, though I do believe that the Bronica systems are throughly professional tools and worthy of a few superlatives from me as well."

Compatibility Information for Bronica ETR Systems: from 1976 to Present

The Bronica ETR camera was introduced in January, 1976. It was the first of  Bronica's leaf shuttered series, and its basic design and operating system was the foundation for all current Bronica cameras. So far ahead of its time 
was the engineering of this camera, that after more than 20 years, it remains the most advanced professional medium format system available today, while retaining the hallmarks of simplicity and practicality.

The ETR type camera has undergone several changes since the first model, most of them resulting in a change of model name. What follows is a listing of the changes, and the compatibility between accessories and the evolving 


ETR Introduced January, 1976

DESCRIPTION: Modular 6x4.5cm camera system; full system shutter lenses; 120/220 interchangeable film magazines, inserts, Polaroid, 70mm backs; Interchangeable finders, auto/manual metering capability. Patented Speed Grip allows for "35mm" style handling, with winding, firing, grasping, and hot shoe all on the grip.


LENSES: All E, PE lenses, teleconverters; extension tubes and extension bellows (note: Some E lenses carried the designation "MC", referring to multicoating. This designation was used into the mid '80s, until it was felt that the multicoating technique was so universal as to not require that notice).

BACKS: All E 120, 220, 35mm Normal (24x36mm), 35mm Wide (24x54mm), Polaroid, 
and 70mm backs.

INSERTS: All 120, 220 inserts can be installed in any E roll film back (note: never put 120 film on a 220 insert, and vice versa).

FINDERS: All E finders: waist level, sports finders, prisms - AE, AE II, AEIII, high eyepoint (action), rotary; angle viewfinder, and multi-scope. 
Please note: The AEIII cannot be used in Auto on the ETR, manual only. The M/C buttons are used to activate/de-activate the finder. Also, when any AE finder is attached to an ETR and left in the "off" position, the camera will 
only have 1/500th second available. Metering displays of the AE, or AEII finders on ETR cameras must be activated by depressing the switch on the front of finder.

GRIPS: All Speed Grip E, Motor Drive E, Winder E, "L" grip, "T" grip (both discontinued in '79), Quick release adapters E, Rotary Tripod Mount with E adapter.

SCREENS: All E, Ei screens ( Ei screens have a transparent window for the confirmation and ready lights of the OTF-TTL flash system).

MISCELLANEOUS:All rubber eyecups (square style, # 2720) for prisms AE, AEII. AEIII uses #2722 small, or #2723 large. Diopters: Same as rubber eyecups, #2610 - #2636 (AEIII uses variable with two available "helper" diopters, #2730 - #2732). Lens accessories; all filter thread sizes of lenses are ø62mm except original 75mm (ø58mm), the 500mm E (ø95mm), the 500PE (ø122mm), and the two Schneider Variogon zooms (ø95mm).


ETRC Introduced October 1977

This camera is identical to the ETR, except having a non-removable magazine. 

All accessories for the ETR ,including 120 & 220 inserts, are compatible (except the magazines, i.e. Polaroid, 35mm,70mm, etc.)


ETRS Introduced January 1979

This camera is almost identical to the ETR. All accessories for ETR are compatible with ETRS, except neckstrap. There are a number of improvements. 
The differences include: 1. everything locked. ( Shutter locking collar has 3 positions (formerly 2; on & off) 2. camera body release locked, but speed grip or motor fires. 3. everything fires. ( Battery check light is inside 
the viewfinder.

With AEII finder, the display can be activated by partly depressing any of the mechanical shutter releases. Strap lugs changed to "D" ring universal, from post & slide lock style. Side mount "blad" style accessory foot is 


ETR-C Introduced January 1979

This is the same camera as the ETRS, but with a non-removable back. All of the improvements that made the ETRS different from the ETR are applied to this version of the ETRC.


ETRS Modification, July 1982

The ETRS was modified, though no model designation changed. The compatibility is identical the '79-'82 versions, but the body and backs changed slightly. This version is sometimes referred to as the "plastic" body ETRS and back, for the change in the side panels of the body and backs to polycarbonate. The lens release was relocated to the left side of the body. The backs changed the insert release from the single tab with the coaxial lock to two independent tabs which must be squeezed simultaneously.


ETRSi Introduced October 1989

The ETRSi is an improved version of the ETRS. Compatibility between all previous accessories is nearly 100%. The battery compartment door (ETRS- #2912) was enlarged, and is now the same as the SQ style (#1912). The Motor 
Drive E (now discontinued and replaced by the Winder E), will operate with the ETRSi, but may require adjustment as the body is slightly wider than the ETRS. The focusing screens have a transparent window for the OTF LED 
information, but are forwardly and backwardly compatible. If OTF is employed, older "E" screens will convey the info as slightly diffused.

CHANGES: Warning in the viewfinder when multiple exposure lever is engaged. Mirror lock-up. Recessed shutter speed dial; eliminates accidental speed changes; also "B" (bulb) setting on the shutter speed dial. OTF-TTL flash 
capable. Attachment ports for the magazines enlarged and beveled on the body, to allow for easier back installation.

Interior of body coated with a sound and light deadening material; reduces internal reflection, and makes the camera quieter. Lens release relocated to front of body. Rubber grips added to the sides of lower body, for easier 

BACKS: The backs have a locking darkslide, designated by a grey handle. The film advance grasp on the insert changed to a folding crank. The pressure roller tension was increased for theoretical film flatness improvement. The body/back interface pin housing returned to a substantial metal collar. Internally, the counter mechanism and gears were revised for greater reliability.




AE finder; introduced January '76, EV 4-17, Auto or manual metering finder, LED array, required depressing front button in finder to activate display (9 contact pin array). It can be used on any ETR type camera.

AEII finder; introduced January '79, identical to AE, except display can be activated by any of the mechanical releases on body (10 pin contact array).

AEIII finder; introduced October '94, Auto or manual metering finder, EV 1-18 (4 stops more sensitive than previous models), Spot or averaging meter selection, LCD display (using far less power than previous models), variable diopter, built-in eyepiece blind for long exposures on auto, auto exposure 
memory lock.


Motor Drive E, introduced October '76, 1 frame per second continuous or single frame operation, using 8 AA batteries, remote activation and power capable, leather handstrap.

Motor Winder E, introduced October '88, 1 frame every 8/10th second, uses 6 AA batteries, no remote 
activation, power, or handstrap available. Much easier to sequence to body



Compatibility Chart for Bronica SQ systems: from 1980 to present 

The Bronica SQ camera was introduced in October, 1980. Bronica made it's reputation creating innovative 6x6 cm square format cameras; many medium format "firsts" were of Bronica's design. The SQ was the first 2-1/4 square to use a mechanical/electronic leaf shutter lens. It was based on the ETR operating system, with a single electronic timer in the body controlling the Seiko #0 shutter in each lens. This provides for the maximum accuracy, and consistency of exposure between each and any of the lenses; yet the maximum simplicity and reliability in the system as a whole, with a mechanical shutter that can be used without battery power.

Changes to the SQ system over time were far less frequent and involved than in previous Bronica model types. What follows is a listing of the changes, and the compatibility between accessories for the evolving models.


SQ Introduced October 1980

DESCRIPTION: Modular 6x6 cm. camera system; full system leaf shutter lenses; 120/220 interchangeable film magazines and inserts, Polaroid, 35mm wide & normal back; Interchangeable finders, manual metering with waist level (MF) or eyelevel (ME). Patented speed grip allowing "35mm" style handling, with winding, firing, grasping, and hot shoe all on the grip.


LENSES: All S, PS lenses, teleconverters; extension tubes and extension bellows made for SQ, SQ-A, SQ-Am, SQ-Ai, and SQ-B (note: the PS designation indicated a redesign of the entire lens line, starting in 1986).

BACKS: All SQ & SQ-i 120, 220, 35mm normal (24x36mm), 35mm wide (24x36mm), and Polaroid.

INSERTS: All 120 and 220 inserts can be installed on any SQ roll film back (note: never put 120 film on a 220 insert, and vice versa).

FINDERS: All SQ waist level, non- metering eyelevel prisms, and manual metering finders. Note: the SQ Auto finders cannot be attached to the SQ body; there is a defeat pin that prevents it. The manual finders have 6 
contact pins; the auto finders have 10. The ETR camera finders can be attached to the SQ cameras via an adapter plate, #1309! This was originally designed to accommodate the use of the High Eyepoint finder #53008. All E 
finders can, however, utilize the adapter to fit on any SQ, but only provide a view of the 6x4.5cm area, with no coupling of metering possible.

GRIPS: The Speed Grip S; the "L" grip, and the "T" grip ( both discontinued in '79). No motor drive was possible for the SQ.

SCREENS: No changes have ever occurred in the screens, so all S screens fit all S cameras.

MISCELLANEOUS: All rubber eyecups for the Prism (eyelevel) finder "S", ME and AE finder "S" are universal (#1714). The 45DS and AE-i auto finder take their own. Diopters: same as eyecups; AE-i and 45DS have variable diopters that have two optional helper diopters. Filter thread sizes of lenses are 67mm, except 40 mm S/PS, 500mm S (95mm), 50 PS (77 mm), and 500 PS (122mm). 


SQ-A Introduced January 1982

The SQ-A was a refinement of the SQ. The contact pin array for the viewfinder was increased from six to ten gold contacts, allowing for auto metering capability with the AE finder S. Also, a mirror lock-up lever was added. The backs were modified slightly, with the ISO dial for the original backs having white and orange numerals, and the new with silver. The darkslide was changed to the locking style; to lock required both the new grey handle slide, and the new silver numeral ISO dial back.

All accessories for SQ cameras fit the SQ-A, however the AE finder cannot physically mount on the SQ; a safety defeat pin prevents attachment.


SQ-Am Introduced January 1983

The SQ-Am was a "motorized only" SQ-A body. Because the SQ cameras, to date, used mechanical shutter releases, adding a motor would be somewhat clumsy to synchronize (the original ETR motor faced this dilemma, and was somewhat fussy to install), and slower. For this reason, it was deemed preferable to integrate the motor into the body. The SQ-Am used six AA batteries to drive the motor, while retaining the small 6 volt battery to power the operating system of the shutter and meter. It ran at two frames every three seconds, and achieved approximately 60 rolls of 120 film per battery set.

All accessories for the SQ, and SQ-A fit the SQ-Am, with the obvious exception of the Speed Grip. A dedicated 9 volt pack using six "C" cells was offered to power the motor for extended periods (#BQ1826) ; the remote 6 volt camera battery (for shutter timing) would be possible to use modifying the battery compartment door slightly.

It is important to note at this point, that in 1986, a complete redesign of the SQ lenses were being formulated at this time. The GS-1 camera, introduced in January 1983, was the first camera and lens system built in the new Bronica factory, which was equipped with the newest and most modern lens testing and assembly gear available in the world. The PG lenses were such an improvement in design and execution over their already high quality and much heralded ancestors, that it became evident that this new approach should be incorporated in all of the Bronica lenses. The "PS" series, a 6x6 version of the "PG" lenses, were phased in beginning in '86, and eventually 
becoming the current line. All "S" and "PS" lenses are compatible with all SQ style cameras. Also, the "PE" lenses were added to the ETRSi camera line in 1992, adding the more advanced "P" series capability to those cameras.


SQ-Ai Introduced October 1990

After much debate and request from the loyal Bronica users worldwide, several key technological improvements were incorporated into the new SQ-Ai. Perhaps most prominently was an add on motor drive, the SQ-i motor, 
requiring an electro-magnetic release on the body. Also featured was a connection port for off-the-film plane flash control. The adapter designed for the Metz units was the Bronica SCA 386. Flashes from Quantum and Sunpack 
also will dedicate to the SQ-Ai. Because this system required a small circuit board to be added to an already fully packed body, more room was created by flattening the battery compartment slightly. This mandated a change from the 6 volt single battery to four 1.5 volt cells (note that the voltage requirement did not change).

The body also incorporated a multi exposure warning in the viewfinder, a 16 second calibrated shutter speed, and a "B" (bulb) setting on the shutter speed dial.

While the backs between the previous models and the SQAi are fully compatible, the newer backs were modified slightly at this time. The ISO dial was relocated to the rear of the back, rather than on the top, so that the speed setting could be seen better with a prism attached. The ISO range was also extended to 6400.

All accessories for the SQ, SQ-A, and SQ-Am were compatible with this body, with several exceptions. Because of the new motor drive and its connection to the body, the winding crank was changed to an SQ-Ai only model. The SQ and SQ-A cranks cannot fit, nor can the Ai crank fit the older cameras. 
Also, the motor drive itself cannot be used on any body but the SQ-Ai. The remote power pack (#1654) for this motor is different than the SQ-Am (#1826), and the electromagnetic release cable is a 3.5mm plug ( #1655), 
instead of the 2.5mm model (#3655).

A new auto prism finder, the SQ-i AE, was introduced in January, 1996. This finder would attach and couple to the SQA, SQ-Am, and the SQ-Ai bodies. It featured auto or manual, spot or average metering, an LCD low power draw display, a variable diopter, 4 stops more sensitivity than its predecessor, a built in eyepiece blind for long auto exposures, and an exposure memory lock. 


SQ-B Introduced February 1996

While all of the remarkable advancements were being added to the SQ-Ai, it became clear that the medium format market required a price sensitive square format system for students, as well as the seasoned pro who needed no bells and whistles. Thus, Bronica introduced the SQ-B camera. It was sold as a kit; with body, back, 80mm PS/B lens, and waist level finder included in a single package. The SQ-B was nearly identical to the SQ-A, but had no contacts in the viewfinder area. Any SQ type prism could be attached, but because no power could be supplied to the finder, no metering capability would occur. Also, because the finders couldn't meter, the back supplied with the SQ-B has no ISO dial. The shutter speed range was the same as the SQ-A, with 8 seconds to 1/500. The SQ-B retained the mirror lock-up feature of the SQ-A.

The 80mm PS/B was optically identical to the PS version, but the A/T selector switch was eliminated. In short, everything that could be removed from the SQ-Ai comfortably was, to make the camera as cost effective as possible.

All of the lenses, finders, screens, backs, inserts, and the speed grip for the SQ cameras fit the SQ-B. The winding crank, battery, battery compartment door, and remote battery pack are the SQ and SQ-A type.


Batteries and Bronicas

Today, virtually everything man made that measures time uses an electronic timer. Small, portable timers (watches, pacemakers,etc.) use batteries. All cameras have timers for shutters, and all modern cameras use electronic timers, and therefore, use batteries.

Batteries differ in size, shape and cell type. The type of cell, and its chemistry determines its voltage, voltage stability, useful temperature range, shelf life, and discharge character. When you're looking to put a battery in a Bronica, there are three available cell types

  •     silver oxide
  •    alkaline manganese dioxide
  •     or lithium cells


It is the best battery for a Bronica ETRSi, an SQ-A,SQ-B, or a GS-1.

The silver oxide battery has been the old standby for years, and for good reason. It has excellent voltage stability, the best longevity, wide temperature latitude, good shelf life, and a predictable (and comfortable for the power requirements of a camera) discharge character. It is has a high up front cost, perhaps three times as expensive as alkaline, but can last three times longer.


It's the recommended cell for the SQ-Ai. More on the reason for this later.

Next is the alkaline manganese dioxide battery, known simply as the alkaline. It has good voltage stability, reasonable longevity, wide temperature latitude, good shelf life, and a predictable discharge character. It is also the least expensive cell, and works well in all Bronicas.


The lithium cells have been a disappointment for use with Bronicas. The performance of lithiums vary greatly, as there are several types. They can be engineered for high amp draw, and lower shelf life; or low amp draw, but 
longer shelf life. They have the potential for the highest energy density per volume of any low cost cell, but the trade off has been made, in "consumer" applications, for long shelf life. This allows these cells to be terrific for hearing aids, and pacemakers....but poor for an intermittent high amp draw requirement like a Bronica.


The following chart outlines the recommended cells for all of the recently manufactured Bronica cameras.


Best: Silver Oxide 6V (544,PX-28)
Good: Alkaline 6V (544A, Etc.)
OK: Lithium 6V (544L)


Best: 4 Silver Oxide (MS-76)
Good: 4 Alkaline (MS-76A)
Forget It: Lithium

SQ-Ai with AE finder*

Best: 4 Alkaline (MS-76A)
Good: 4 Silver Oxide (MS-76)
Forget It: Lithium


Best: Silver Oxide (6V,544,PX-28)
Good: Alkaline 6V(544,Etc.)
Forget It: Lithium

*The AE finders for the SQ-Ai cameras represent an unusual situation, in that it is preferable to use the alkaline cells, rather than the silver oxide. The silver oxide, the tenacious cell that it is, allows there to be a brief period, when it is near exhaustion, where the low voltage thre.shold of the AE is skirted due to the power demand of the electromagnetic release mechanism. The result is insufficient voltage to set the correct shutter speed in the Auto mode only. It can occur for a roll of film, or the precaution has been issued to prevent this. This situation is not present in the older SQ-A, SQ-Am, SQ; or the ETR style cameras. It also doesn't affect the GS-1.