RB Super D * RB Series B
ALSO EARLER MODELS INCLUDING
Series B * RB Series D Auto * RB Auto * Auto Jr. RB Tele * RB Jr.
|Principles of the Graflex
Graflex Photography is built around three simple elements:
1. A reflex viewing-focusing optical system that shows on a ground-glass
an exact, erect image of the scene to be photographed, without parallax
and with the same depth of field as the image on the negative;
2. a multiple-speed focal-plane shutter giving a wide range of exposures up to 1/1000 with efficiency and reliability; and a
3. wide selection of sensitized materials through availability of various types of holders, and a quick, simple, positive means of attaching them to the camera.
first two elements are interlocked to make operation rapid and simple;
the third gives an unlimited choice of emulsions to suit all conditions
and types of work.
1. Reflex focusing is illustrated in Figure 1. Light enters the camera through the lens 5 and is reflected upward by the mirror 3 to the ground-glass screen 2; visibility of the image is improved by the light-excluding focusing-hood 1. The lens is focused by focusing control 4. Since the focusing screen and the film are equidistant from the lens, sharpness of the image
on the ground glass indicates the sharpness of the negative. The mirror automatically lifts away just before exposure, so that light from the lens passes directly to the film to form the image.
2. The focal-plane shutter is a curtain (Figure 2) of special cloth containing five slits of different widths. It is carried on an upper roller and winds down across the film and onto a lower roller when released by movement of the mirror. (Its action may be observed with the film holder removed from the back of the camera.) The time of exposure is governed by two variables:
a. the width of the slit (or curtain aperture), and
b. the speed of the curtain (controlled by tension of the lower roller) .
The shutter-speed plate (Figure 6, 6a, 6b) shows the various exposures resulting from different combinations of slit and tension.
Directions for the shutter controls will be found on pages 9,10,11,12 and 13.
3. Sensitized materials to receive the image are carried in a suitable holder (Figure 8) behind the curtain. Several types of accessories are available for this purpose: sheet film holders. plate holders, film pack adapters and sheet film magazines for all sizes of the Graflex; and for certain sizes only there are plate magazines and roll holders. Instructions for using the last three types of accessories are supplied with them.
A fine camera is primarily an instrument rather than a machine, and the reputation which Graflex products have won for sturdiness and continued functioning under adverse conditions should in no sense be an invitation to abuse them. To insure the long and trouble-free life of which your camera is capable, study and follow these directions as you handle it for the first time. Above all, do not twist any knobs or push any buttons on this camera until you know what this pamphlet tells about them. Do not lend your camera to anyone not familiar with it without instructing him in how to use it. If you lose this book, write us for another.
Since the manner of operating all Graflex cameras is the same in all important details, this manual applies equally well to all current and most older models. Minor points of variation between the different models will be clearly emphasized and explained. These differences relate principally to 1. opening and closing the camera, 2. interchanging lenses, and 3. focusing controls.
The National Graflex, RB Series C, and the 5 x 7 RB Home Portrait Graflex and some of the earlier folding cameras, are covered by their own special manuals.
Series B * R.B. Series B * R.B. Series D * R.B. Super D *
R.B. Tele * R.B. Auto (Stationary Back) * Auto Jr. * R.B. Jr.
The top is first opened (Figure 3) by releasing the spring catch L at the upper front of the camera, pulling the top up and hack until the focusing hood is fully extended and straightening the two side braces until they lock in position.
Then open the front of the camera by turning the knurled focusing control S forward (clockwise); this moves the lens carrier and lens forward and automatically releases the front door so that it snaps up. The opened door of the R.B. Super D and Series D serves well as a lens-shade by virtue of the side flaps.
R.B. Auto Graflex
Open the top as directed above. This model has an extra-long bed, which accommodates the additional bellows extension and also serves as the front door. Release it by pressing on the bed-release button under the leather at the top of the extreme front of the camera, and press the bed firmly down until the bed braces snap into position (Figure 10).
There are two focusing controls for the R.B. Auto Graflex (Figure 10, Page 24): one at the lower right front corner of the body, is used for normal work; the other, on the right side of the bed near the front, comes into use when the bellows are given considerable extension--as when focusing at very close range.
Further data on close-up work with the R.B. Auto Graflex will be found on pages 24 and 25, and other specific information on page 9.
Rack the lens all the way back into the camera and close the front door or bed, making sure that it snaps securely.
To close the top, fold the braces and push the top down, folding the focusing hood carefully back into its original position. Make sure the top is securely held by the snap-catch at the front.
Important: After closing the camera remove all tension from the shutter mechanism by releasing both the aperture and the tension controls to their lowest settings, and raise the mirror by pressing release lever. (See bottom of page 9).
Note: Some large lenses when racked back may not permit the mirror to rise fully. In such an in stance, release the mirror before racking the lens into the camera. This will prevent the mirror from accidentally striking the lens mount.
|The shape of the Graflex and the position of its controls permit it
to be held and operated comfortably and without strain. The fact that an
erect image is visible in the ground glass, right up to the instant of
exposure, further simplifies the handling of the camera.
Rest the camera in both bands, with the fingers under the corresponding front corners of the body (Figure 4). The thumb of the left hand falls naturally on the release lever, while the right thumb and the forefinger are in position to grasp the focusing knob S. To steady the camera, hold it firmly against the chest. To reset the controls after exposure, tilt the camera to the left so it rests on the left hand and forearm.
(See below for Super D with automatic diaphragm).
The Mirror must be set for focusing; see page 11. Information on the ground glass is on Page 14.
Moving the lens away from the film focuses on close subjects; moving It toward the film focuses on more distant subjects.
Focusing will be greatly facilitated by a large diaphragm opening. This gives a bright image, and in addition the shallow depth of field will make critical focusing an a specific point or plane much easier and more precise. Don't forget to set the diaphragm before exposing!
The automatic diaphragm, as used in the Super D Graflex, permits you to focus with the lens wide open and then automatically stops itself down to a pre-selected aperture while the mirror is rising before exposure. This facilitates focusing with a filter in place, with poor light, with a very bright light that blinds the eyes, and whenever a critical focus is desirable. Since the depth of field (see page 19) is shallower wIth the lens wide-open than when it is stopped down, the plane of sharp focus is more clearly defined and accurate focusing is more rapid and certain.
To set the automatic diaphragm, pull out the stop-pin (left in Figure 5) and move it until its pointer ispposite the aperture required by light conditions and shutter speed; release the pin 50 that it engages the corresponding hole and remains in position. Then set the mirror, slit and tension as directed on page 10. Lastly, move the aperture lever to the right (counter-clockwise) until it engages and is retained by the catch. (Figure 5 shows this position.)
When the mirror-release is depressed, a connecting mechanism within the camera lifts the catch so that the spring mechanism in the lens mount closes down the diaphragm, even to the smallest stop, before the curtain begins to open.
Note that for very critical exposure control, half-stop settings are available between f/5.6 and f/16. If it should be desirable to stop down the diaphragm before exposure, slowly depress the mirror release part.way until the diaphragm is heard to close; further pressure will release the mirror and curtain. Naturally you need not set the diaphragm full-open belore exposure if you prefer not to for certain special conditions.
Series B. * R.B. Series B . * Auto Jr. . * R.B. Jr.
The lenses of these Graflex cameras thread directly into fixed lens boards, and are removed by simply turning the entire lens barrel counter clockwise. Be sure to grasp the barrel itself, near the lensboard, so that you will not accidentally loosen the front cell of the lens. If the lens does not free easily, slightly loosen the four small screws in the face of the lensboard.
Certain telephoto lenses are suitable for use with these cameras. They may require an adapter or intermediate collar threading into the open mg in the lensboard. Focusing and exposing with these lenses is carried out in the normal way.
R.B. Super D . * R.B. Series D . * R.B. Tele Auto (Stationary Back)
Lenses of these models are fitted to removable lensboards. They are removed by pushing lens and lensboard straight up, against a hidden spring, until the bottom of the lensboard is clear of the lower retaining strip; it may then be swung out and down, free of the camera. If the lens has a very krge diameter it may be necessary to unscrew it from the lens board before the lenshoard can be removed from the camera.
To replace the lens and lenshoard, reverse the above procedure- with the bevelled edge of the lensboard at the top, so that it fits into the slot with the hidden spring. Be sure to pull the lensboard all of the way down behind the lower retaining strip.
Lenses in barrel mount and in automatic diaphragm mount are fully interchangeable in the Super D Graflex, without special adjustments. The automatic diaphragm should be set before it is fitted into the camera.
R.B. Auto Graflex
Lenses of the R.B. Auto Graflex are fitted to removable lensboards. held in place by a slide-lock and retaining strip similar to those used on the back of the camera to retain the film and plate holders. To remove lens and lensboard, move the slidelock to the left and up untfl the top of the lensboard is free; swing the top of the lenshoard out and lift the bottom out from behind the lower retaining strip.
To replace a lensboard, reverse the above procedure--making sure that the bevelled edge of the lensbeard is at the bottom.
This type of shutter is so-called because it operates close to the focal plane of the lens (the location of the film). Its principal advantages are:
The controls of the shutter and mirror, shown in Figure 3, are located at the right rear of the camera. The release lever, which is depressed to make an instantaneous exposure, is actually the mirror release and is located at the front of the left side convenienfly under the left thumb. On many models each of the shutter and mirror controls has an identifying letter stamped into it. These letters are the same on all models of the Graflex (except the National Graflex which has its own manual) although the form of a particular lever or key may differ some what from one camera to another. The letters used below refer to Figure 3.
The various combinations of the tensions and four apertures provide a wide range of speeds (shutter settings), up to 1/1000. Fig. 6, 6A).
Before actually using the camera, set it on a table and follow the description below by manipulating each control as it is mentioned.
The mirror-setting lever H, just under the aperture control A, (Figure 3) is extremely important because the curtain cannot move (except when set for Time) until the mirror has been set by pressing this lever down and back (toward the rear of the camera). The curtain aperture (slit) to be used for an exposure is set by the aperture control A; and the tension (which determines the speed with which the curtain moves) is set by tension control B. Windows r and G, next to their respective controls, show the settings of these adjustments. Turning A counter-clockwise (clockwise in the Auto Jr.) with the arrow, winds to narrower slits; moving curtain-release lever M toward the back of the camera allows the curtain to unwind to wider slits.
The figures on the scale showing in F indicate the aperture that will next pass across the film when the curtain is released. When set on T (for Time Exposure), releasing the shutter places the slit 0 in front of the film exposing the enitre film at the same time. Operating the curtain-release M a second time closes the curtain.
In the 2-1/4x3-1/4 R.B. Series B, it is necessary to wind A two clicks between settings; the number exactly centered in F indicates the aperture for which it is set. The curtain is closed when any number except 0 (Open) is centered in F.
the correct aperture and tension on the shutter speed plate (Fig. 6). Locate 1/125 on the plate; reading straight up, you will find aperture B, reading straight to the left you will find tension No.5 or L.
Note: A "drop-curtain" exposure of about 1/5 second is obtained with the curtain at 0 and the tension at 6 or H.
The procedure for a Time exposure is somewhat different, because the mirror and curtain are released separately.
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