Zenza Bronica CS-1 User manual

ZENZA
BRONICA
INSTRUCTIONS

Congratulations on your choice of the Zenza Bronica GS-1, a lens shutter type
single lens reflex camera in the 6x7 format.
The GS‘1 provides the professional user with a lightweight and compact 6x7
format single lens reflex of extremely useful versatility and multi-functional
performance, which is based on the history and experience gained in the devel¬
opment of the Zenza Bronica ETRS and SQ-A single Eens reflexes, as well as the
latest technological advances in the electronic field.
The GS-7 has been developed as a full-scale system camera, with a wide range of
versatile accessories and especially with complete film back interchangeability
which gives it multi-format capability for use in a wide field of applications,
Including commercial photography, news photography, scientific photography,
etc., as well as giving this 6x7 format sirigle lens reflex versatility equaE to the
35mm single lens reflex camera.
Although instructions following are based on the GS-1 camera main body, the
ZenzanomPG 100mm lens and the Film Back GS 120, the choice of finder is left
to the discretion of the photographer who should also read the instructions for
the finder chosem The choice of lens, film back and finder should be based on
the type of assignment contemplated by the user.
To obtain best results from the Zenza Bronica GS-1, may we suggest that you
read this instruction manual through carefully, before you even touch the cam¬
era, as your pleasure in using the camera will be even greater if you thoroughly
familiarize yourself with its working parts before loading your first roll of film.

CONTENTS
Specifications of the Zenza Bronica GS-1 .... 2
Parts of the Zenza Bronica GS-1 ..* 4
1. Loading the Battery 7
2. Main Switch . 8
3. Finder Display and Battery Checking . . . , 8
4. Attachment and Removal of Film Backs . . 9
5. Construction of Film Back ..11
6. Film Loading .. I T
7. Film Speed Dial. 15
8. Exposure Compensation Dial ......... 15
9. Film Type Indicator Frame .16
10. Exposure Counter. 16
11. Film Winding/Shutter Cocking. . . 1 7
12. Film Unloading ..17
13. Setting the Shutter Speed Dial .18
14. Shutter Release Button ... . 20
15. Time(T) Exposure . .21
16. Exchanging Lenses.22
17. Interchanging Finders..23
18. Setting the Aperture Ring . 23
19. Focusing Adjustments .............. 24
20. Distance Scale and Depth of Field Scale , . 25
21. Infrared Photography.25
22. Flash Photography ................ 26
23. Multiple Exposures . ... . . . . 27
24. Mirror Lock-Up.23
25. Remote Control Operations.. . 30
26. Interchanging Focusing Screens , 30
27. Removal and Attachment of the Film
Winding Crank Assembly...32
28. Attachment of the Meek Strap 33
29. Facts about the Battery 34
30. Pointers on Shooting.. 35
31. Care of the Zenza Bronica GS-1 ........ 35
32. Depth of Field Tables..37
33. S pecifications of Zenzanon-PG Lenses ... 33

Specifications of the Zenza Bronfca GS-1
Type
Frame size
Film
Standard lens
Filter size
Lens mount
FocLjsing edlustment
Lens diaphragm
Shutter
Shutter release
Fil m vifinding
Multiple exposure
Mirror lock-up
Film back
Finder
6 K 7cm format lens shutter single lens reflex canrvera, with interchangeable lens^ film back,
finder and focusing screen systerm.
55.6 X 69.0 mm (4:5 redo matching the size of the photographic paper),
120 roll film; 220 roll film; 135 roll film in film cartridges; and Polaroid Land Pack films
(with exclusive film backs required for each film type)^
ZenzanomPG IDOmm F3,5r interchangeable type; six elements in four groups; multilayer
anti-re fleet! on coated; 48 ^^ angle of view; F22 minimum aperture; and minimum 0.75 m
focusing distance.
72 mm diameter on IQQmm F3.5 standard lens.
Bronica GS mount (exclusive four-claw bayonet).
Helical focusing system built into each lens.
Fully automatic instant reopening lens diaphragm; 1/2 stop Increments; equal-distant aper¬
ture scale graduations.
Electronic control SEIKO #0 betuveen-lens leaf shutter; shutter speeds from 16 sec. to
1/500 sec., without intermediate settings, plusT {time exposurel, 6 Ibulb) and A (automatic
exposu re).
Electro-magnetic shutter release system; also has electro-magnetic cable release system.
Film winding crank, with one full forward revolution or ratcheted winding action.
Muitiple exposure possible with multiple exposure lever on camera body.
Continuous mirror lock-up possible with mirror lock-up lever on camera body.
Daylight loading interchangeable type; exclusive film backs for 120 and 220 roll films {6x7,
6x6 and 6x4,5 fornnats), 135 roll film 124x36 and 24x66 formats) and Polaroid Land Pack
film; with ASA/ISO film speed dial and exposure compensation dial (coupling to finders
with built-in exposure meter).
Interchangeable type; shows 94% of the actual field of view (which does not change upon
exchanging finders).

Focusing screen
Finder indications
Fiash syfichroniiation
Battery checking
Battery
Dimensions
Weight
Interchangeable type^ standard type^ supplied with camera, Kasfull^rea matte screen.
Shutter speed, etc,, is shown at the top of the finder area, outside the screen area: 5 digits,
7 segments and dot indication, depending on finder attached.
X'^etting (for all speeds up to 1/500 sec.l; sutonnatic flash control, with direct exposure
metering of film surface is possible (with exclusive dedicated electronic flash unit).
Steady illumination or flickering of shutter speed display In finder, with helf-stroke of the
shutter reJease button.
Single 6 volt silver oxide or alkalina-menganese battery.
106.5 (wide) k 99 (high) x 80 (long) mm — GS-1 main body only.
106.5 (wide) X 116(high) x 196.5 (long) mm — GS-1, with standard lOOmmlens, Film Beck
GE 1 20 and Waist-level Finder G.
630 grams [GS-1 main body only, without battery).
1,S30 grams (GS-1, with standard IDO mm lens. Film Back GS 120 and Waist-level Finder G
but without battery).
The above specifications are subject to changes without prior riotice when necessary for the
purpose of improving performance.

Focusing ring —
Flash synch socket
Shutter release button
AE finder
Shutter speed dial
Shutter speed seal
window
Screen removal
Heft}
Mirror lock-up lever
Aperture ring
Depth of field scale
Distance scales
Lens alignment dot
LED display plate
Film winding crank
assembly release lever
Screen removal lever
(right)
ASA/ISO film speed
contacts
Manual film winder
Spool holder

Fihder release button
Film winding crank
Multiple exposure lever
Neck jtrap eyelet
Back cover release button (bottoml
Back cover release button (top)
Main switch
Shutter speed dial lock button
Depth qf field preview lever
Lens release button
Neck strap eyeJet
Electro-magnetic cable
release socket
Film back release
button
Dark slide slit
Film plane mark

Time exposure
lever release
Accessory contacts
Film winding
coupler
Accessory guide sockets
Film winding crank assembly
Exposure compensation dial lock button
— Time exposure lever
Exposure compensation dial
Tripod socket
Battery chamber
cover
Battery chamber
button
ASA/ISO film
speed scale
ASA/ISO film
speed dial lock
button
Exposure counter window
Film type indicator frame

The elactr&nirallv'ConUiOlled
shutter and, of course^, the
etectro-magnatic shuttBr rafease
system, wiEt not work without
loading the battery- one
6 voft silver oxide battery or
alkaline-monganEse battery,
* The battery may be obtained
' at any photographic eoiuipmert
i or electrical appliance shop.
A. Depress the battery chamber
button with your finger and, at
the same tinne, move the battery
chamber cover in the arrow-in^
dicated direction. The cover will
corT>e off quite easily.
B. Coincide the plus 1+1 and
minus (—) marks on the battery
with similar polarity Indications
in the battery chamber, Then,
push in the battery.
Insert the battery chamber cover
into the BATTERY end first
and then move the cover in the
other direction until it locks.
* The shutter will not operate
when the bartery is loaded with
polarity marks reversed.

2 I Marn Swrtch
The main switch i£ located on
the upper left side of the main
body. There will be no opera¬
tions unless the main switch
is pushed down {i^e.^ switched
ON).
* There is no power consump¬
tion, even with the main switch
ON. Howeyer, the batterv'life
will he shortened when the shut¬
ter release is stroked haifways
and the shutter speed display
lights up Steadily or flickers.
Therefore, switch OFF (push
up) the main Switch when it is
not planned to use the camera
for soime times.
(D
3 I Finder Display and Battery Checking
A. An LED display located over
the top center of the focusing
screen shows the shutter speed,
etc., which is viewed laterally
rowersed with the waist - I eve I
finder.
Since the LED display differs
with the finder in use^ please
read the instructions supplied
with the finder for correct usage
and reading.
B, Turn OIM the maim switch
and then stroke the shutter re¬
lease button half ways. If the
LEO display in the finder lights
up steadily or flickers, as the
case may be, the battery Is
loaded properly and there is
sufficient power for ope ratio rts.
* If the LED display does not
light up steadily or does not
flicker, as the case may be,
(1j the battery is not loaded
properly or (2) the battery is
completely drained and should
be exchanged.

4
Attachment and Removal of Film Backs
The film back is a film cham¬
ber that cen be attached or de¬
tached freely from the main
body, thus permitting free bx -
change df film types, at all
times. Since the main body and
film back are alvt^eys fully cou¬
pled^ upon connection, always
turn the film winding crank
completely one time, upon at¬
taching the film back. If wir>d-
Ing is not possible, all prepara¬
tions for taking the picture have
been completed. If winding is
possible, however, rotating the
film winding crank until it stops
automaticallv takes care of the
incdrnpleted action, whether un¬
cocked shutter or film not ad¬
vanced. This means,, of course,
that it'^s possible to choose the
film type most suited for the
shot, even midway in a roll.
An ASA/tSO film speed dial
and an exposure camperiiSation
dial are available on the film
becks. When used for setting the
film speed of the film loaded
in the film back, there is auto¬
matic coupling when finders
with builit-ln exposure nwters
are attached on the main body.
This will, of course, be very con¬
venient when using films of ctif*
ferent sensitivities in the film
backs.
* Make full use of film back in¬
terchangeability, in the follow¬
ing manner: —
1. Take full advantage of the
multi-format superiority of the
G5-1 and use film backs in
many different formats, which
will not only give you different
effects but will economiz;a on
film,
2. Take your pictures in color
and black-and-white, and in dif¬
ferent film speeds, as required.
3. Keep a sufficient quantity of
preloaded film backs on hand
and speedy, continuous shoot¬
ing will be possible,
4^ Don't waste unsuitable film
used In a previous session but
simply load up a new fiirn back
with the required film type.
5. The Polaroid Film Back can
be used for instant color or
black^ndi-white pictures, when
in 3 rush, or used for checking
composition or lighting effect,
before taking the actual picture,
• Film backs are gvailgbfa op¬
tionally and tha type meeting
the requirenrienTs of the photog¬
rapher should be chosen.

A. T o attach the film back to
the malrn body^ simply insert the
larches at the upper end of the
film back into attachment open¬
ings at the upper end of the
main body. Then, press the
lower end of the filnm back
against the main body until it
locks sacurely.
* The dark slide must be with¬
drawn from its slit, upon attach¬
ment of the film back to the
main body, as otherwise the
shutter cannot be released.
B. T he dark slide must be in¬
serted into the dark slide slit,
for removing the film back from
the main body* Insert, with the
® mark at the top, as illustrat¬
ed, and then push in all the way.
* There is danger of the film
back becoming detached from
the main body, if the dark slide
is left in its slit while the camera
is being carried. Therefore, make
it a rule to withdraw the dark
slide whenever the film back is
attached to the main body.
C, D epress the film back release
button and the lower end of the
film back can be removed, as
illustrated. Simply shift the film
back up slightly and pull it
away,
* The dark slide cannot be
withdrawn from the film back,
when the film back is detached
from the main body.

5 I Construction of the Film Back
Fjinn holder
A. The film back consists of a
fjim hoJfJerand film back frame,
with exclusive film backs avaiJ-
able for 120 and 220 roll films.
The film holder is not only de¬
tachable from the film back but
^Iso has a built-in film winding
mechanism.
* Read Instructions supplied
with the Film Back G3 135 for
loading 135 roll film.
B. The film back frame has a
base with a dark slide slit and a
back cover with an ASA/ISO
film speed dial, an exposure
compensation diat and a film
type indicator frame. The film
back frame completely encloses
the film holder and shields it
from outside light, as well as
connecting it to the main body
and also coupling with finders
with built'in exposure meters.
6 I Film Loading
To opan the back cover,
squeeie the top and bottom
back cover release buttons, in
the arrow-indicated directions,
at the same time and the back
cover will open.

C. Ttie film holder has two
spool holders, with The right one
fqr the fresh film spcjol while
the left one is for the empty
take-op spool. The top spool
holder is opened^ as illustrated,
by skiding the film [spool) in
the arrow-indicated A direction.
The new film spool shojid be
coincided or the right-side bot¬
tom shaft, which is fixed, after
which the top spool holder
should be closed to engage the
spool.
* The spool holders qn the top
will be locked securely, when
the back cover is closed.
B, It will be possible to take
out the film holder, upon open¬
ing the back cover.
Black surface ot Header must
f^ca out
empty take-up spqol
Fresh film spool
D. After loading the fresh film
spoof properly, draw out the
leading and of the film and turn
it across the film pressure plate
(as illustrated)^ Run it across
and turn it over to the take-up
spool. Insert the leading end
into the slit of the take-up spool
and wind slightly until securely
engaged.
* The inside black surface of
the leader must face out when
running across the pressure
plate, in this case.

E. Rotate the manual film
winder on top of the film holder
in the grrqvv'indicated dirgction
and wind up the film leader.
When the starting point, or ar¬
row mark, appears, align it with
the triangular ▼ start-mark on
the right top side of the film
holder^ Then, stop rotation.
F, The starting point can also
be aligned with the start-mark,
with the film holder loaded in
the film hack. |n this case,
simply rotate the film winding
crank of the main body to align
the start-mark. This method is
preferable since there will be
coupling with the camera body
mechanism, from the beginning.
* if the film is not advanced
when the film winding crank
is rotated, however, the film
holder Is not loaded properly in
the film back and/or the camera
main body may be set for multi¬
ple exposures. In the latter case,
return the multiple exposure
lever to an upright or vertical
position,
(See "Multiple Exposures" on
page 27,)

G+ Close the back cover, by
pressing it firmly against the
right side of the film beckbese^
as illustrated. The back cover
will automatically lock and
close.
The same operation will close
the back cover when the film
back is detached from the main
body.
H, Upon loading the film, ro¬
tate the film winding crank until
it stops to place the first frame
into place for taking the picture.
The exposure counter will also
change from '^S" to "1", with
the film advanced and the shut¬
ter cocked.
I. The manual film winder is
used to place the first frame
into position, when the film
back is detached from the main
body.
The manual film winder will not
stop rotating, evan when the
film is rn place for the first
frame, but should be rotated
2 or 3 times more, in order to
take up slack in the loaded film.

not mistake the dotted lir>e be¬
fore the arrow rrark for the
start-mark.
* For the use of film backs
other than the 6x7 formal, read
the instructions supplied with
the film back.
7 I Film Speed Dial
Set the film sensitivity of the
film loaded in the film taack^
when using finders with a built^
in exposure meter. To set the
film speed, depress theASA^ISO
film speed diet lock button and,
at the same time, rotate the
ASA/iSO film speed dial and set
the required film speed to the
index. The dial has click-stops
at 1/3rd Incremants.
8 1 Exposttire Cornpen-
I sation Dial
Exposure compensation up to
±3 Stops is possible at 1/3rd in^
crements. To set the required
compensation,^ slide the expo¬
sure compensation dial lock
button, in the arrow-indicated
direction, than rotate the ex¬
posure compensation dial, as
required,
Wheri compensation is not
needed, simply set to "OT
where it is locked.
* There will be no effect on the
exposure, no matter where the
ASA/ISO film speed dial and ex~
posure compensation dial are
set, when a finder with a builtnn
exposure meter is not used.

E
I F(fm Type Indi¬
cator FrajTia
10
EKposure Counter
Upon loading the film, tear off
the end flap from the empty
film package and insert it in the
film type indicator frame. This
will help you keep track of the
film loaded in the film back,,
even when two or more film
backs are used with different
types of films.
The exposure qountar is an addi^
tive type which $how$ the num¬
ber of frames exposed. Starting
from "S*', the counter on Film
Back GS i20 fGx?) shows num¬
bers from 1 to 10, while Film
Back GS 220 (Bx7) shows num-
bars from 1 to 20. ^‘S'% "10"
and ^'20'" are orange-colored, in
the above case, and all other
numbers are white.
120
220
Or5ng>a White
Orange
1 r--
hr- ^
S — 1 2 3 4 5 S 7
S 9 10 — I
S ^ 1 . . 4 *6,8'10- 12-
14-
16-18-20 —
1 -N/-
Orange White Orange

Ill Film Winding/
The filrri winding crank auto¬
matically stops, wh@n rotated
completely one time in the for¬
ward direction,, with film ad¬
vanced one frame and shutter
cocked, at the same time.
Or, short, rapid strokes, up to
an accumulated full rotation,
will also do the same job be¬
cause of a ratcheted mechanism.
* The mirror lock-up lever must
be vertical at all times, except
when shooting with the mirror
locked up.
(See "'Mirror Lock-Up" on page
2e.}
12i Film Unloading
A. After the 10th exposure of
the 120 roll film {20th exposure
of the 220 roll film), continue
rotating the film wirtding crank
and the film only will be ad¬
vanced until the remaining film
and leader paper are wound up
on the take-up spool.
Open the hack cover When there
IS no resistance in the wir^ding
action,
B. Remove the film holder and,
while preventing the loose film
from unwinding, take out the
take-up spook Seal the exposed
film and return it to its original
box until development.
Load and unload film awev
from direct sunlight and/or
strong illumination.

1 1 3 1 Setting the Shutter Speed Dial
Ar The shutter speed scale is
viewed in its window over the
shutter speed dial. The numbers
□ n the scale are shutter speed
settings, with numbers 1 to 16S
"full numbers and numbers 2 to
500 fractions of a second. For
example, "16S" Is 16 seconds,
''2" is 1/2 see. and "SOD" is
1 /500 sec,
A is the setting for aperture-
priority AE (automatic expo¬
sure) when a finder with a built-
in exposure rneter is attached,
B (bulb) is the setting used to
keep the shutter opened, as long
as the shutter button is de¬
pressed. However, since power
6 The numbers on the scate
are color-coded in red and
white. Red-colored numbers are
full number settings of 1 second
and longer while white-colored
numbers are settings from 1/2
to 1/500 second, as well as the
letters "A" and "'B".
The shutter speed can he set
before or after film winding.
(For "Time (T) Exposure", see
page 21.)
is consumed during this time,
the use of T (time) exposure
is recommended for exposures
longer than ong minute.
A
SCO
250
125
60
30
15
8
4
2
I
25
4S ^
as
les .
B
White
Rnd
tWhite