Pentacon Six ttl prism manual cover


The TTL Prism Attachment can be used instead of the finder hood or the usual pentaprism in connection with the PENTACONsix or PRAKTISIX camera. It enables partially integral light metering to be performed, based on the modern, technically accurate internal measuring system. All factors making any difference with regard to the exposure are automatically taken into account. Correction of exposure values is no longer necessary, for instance in connection with close-up bellows or with filters.
We request you to study these instructions with great care, since we can accept no liability for any damage caused by improper handling of the equipment.
Pentacon Six ttl prism


Control parts:

1 Switch knob for measuring circuit

2 Window showing meter needle and centering mark

3 Control knob, consisting of inner section with scales (5) and exposure speed ring (4)

4 Exposure speed ring

5 Film speed scales

6 Index mark for setting film speeds

7 Aperture ring with scale of f numbers

8 Index mark for measuring with lens at taking aperture

9 Index mark for f numbers, exposure speeds, or mark 8

10 Ocular mount

11 Mask for eyepiece of viewfinder

12 Control knob for mask

13 Locking knobs

14 Battery chamber with cover

15 Section showing meter needle and centering mark

16 Boundary lines of measured area in viewfinder

17 Manual stop-down lever on taking lens

Pentacon Six ttl prism


How to fix the TTL Prism Attachment to the camera
To fix the attachment to the camera, depress the two locking knobs, (13) simultaneously. Now place the attachment from above on the four connecting bolts of the camera. Leave hold of the knobs, and the attachment is fixed tightly to this camera. If the EverReady Case for PENTACONsix or PRAKTISIX with pentaprism is being used the TTL Prism Attachment can remain on the camera.
Pentacon Six ttl prism


Functioning and design of the TTL Prism Attachment
The roof-shaped pentaprism; incorporated in the TTL Meter Attachment reveals to the camera user a correct-sided, upright finder image viewed through the ocular lens which gives an approximately 2.5-fold magnification. With the standard 80-mm lens in the Camera, this means a total magnification of the optical system of about 0.8 times, Like on the pentaprism without exposure meter, the mount of the ocular is designed to accept extra devices. such as Accessory Shoe, Eyecup, Mount for correcting lens, Angle Finder. or Focusing Telescope.


The Exposure Meter System
The measuring principle
The photoelectric exposure meter in the TTL Attachment works according to the principle of partially integral measuring, i e., measuring takes place integrally within the area, 25 mm in diameter (16), as marked in the viewfinder. This arrangement has the advantage that special allowance is made for important sections of the image. The exposure meter system is constructed in such manner that the light required for measuring is taken from the image-erecting surface of the pentaprism and conducted to the CdS photo resistor. Power source is a mercury-oxide battery Mallory PX 13. The metering process is quick and simple, The meter needle has only to be moved to coincide with a fixed mark by rotation of control knob (3). Movement of the meter needle may be watched either through the ocular, in the section (15) next to the viewfinder, or in the window (2) on the top of the TTL Attachment. There are two possibilities of internal measuring with the TTL Attachment:
a) measuring with lens at full aperture.
b) measuring with lens at taking aperture.
Scales for film speeds f stops, and exposure speed
On knob (3) are the two scales indicating the film speeds. Ring (4) bears the exposure speed numbers and the index mark (6) for setting the film speeds. The separate ring (7) below knob (3) shows the f numbers and the index mark 8.
film speed scales

Control knob (3) is provided with two scales far setting the film speeds in DIN arid ASA values. Lift the exposure speed ring (4) in axial direction and move it to set the speed of the negative material in the camera. Ring (4) clicks in at every DIN value also at the intermediate stops between the values on the scales. All the values listed in the table below are adjustable on the TIL Attachment. The film speed values printed in special type indicate the numbers marked on the scales.
Pentacon Six ttl prism


DIN

ASA

DIN

ASA

9

6

21

100

10

8

22

125

11

10

23

160

12

12

24

200

13

16

25

250

14

20

26

320

15

25

27

400

16

32

28

500

17

40

29

650

18

50

30

800

19

64

31

1000

20

80

32

1250

   

33

1600



When the Fresnel lens (207.251) is used in the camera set the film speed to the white point at the right side of the triangular mark. Non-frosted viewfinder lenses are not suitable far exposure metering.

The power source
Power source for the photoelectric metering system is a Mallory battery of the PX 13 type. The cover of the battery chamber (14) on the side of the TTL Attachment is unscrewed with the aid of a coin and the battery inserted. The plate of the battery bearing the plus sign (+) must face the cover which bears the some sign on the inside.
the exposure meter device is switched on and off by means of knob (1). Turn the knob to the right as far as it will go, so that its arrow points to the green mark, and the exposure meter is switched on.
The red dot indicates the "off" position. After the lightmeter reading has been taken, please do not forget to switch off by moving the knob back in the anti-clockwise direction.
A bridge circuit is employed in the metering system, thus eliminating the necessity for checking the working voltage of the battery. Nevertheless, it is advisable to insert a new PX 13 battery after 1 or 2 years. Owing to danger of explosion, the discarded mercury oxide battery must not be thrown into the fire.


Measuring the exposure time
A Measuring at full lens aperture
1. Setting the film speed. This is done by lifting up outer ring (4) of knob (3) as far as it will go, at the same time turning it until the white mark (6) Paints to the speed value of the negative material in the camera. The ring clicks in when dropped back. Also intermediate values between the numerals and the scale may be selected. (Please note table on page 10).
2. By rotation of aperture ring (7) the widest aperture of the lens in the camera (smallest diaphragm numeral, e. g. 2.8) has to be brought to coincide with index mark (9), where it clicks in. Also here intermediate values are adjustable.
3. Cock the camera shutter.
4. Switch on the metering system by clockwise rotation of knob (1) : Arrow paints to green mark.

5. Direct the camera towards the object to be photographed so that important sections of the image appear within the boundary lines of the area (16) marked in the viewfinder. Move meter needle to the centering mark by rotation of control knob (3). Movement of the needle may be watched either through the ocular, in the section (15) next to the viewfinder, or in the window (2) on the outside. In the latter case, especially under unfavorable lighting conditions (light falling directly on to the ocular), the mask of the ocular has to be moved in by rotation of knob (12) to the right. Also when watching the meter needle through the ocular, it is advisable to insert the lighthood supplied with the equipment into the ocular mount (10) to avoid getting incorrect readings which may result from intense light falling straight on to the ocular.
6. The measuring procedure leads to aperture/speed combinations formed by the values facing each other on aperture ring {7) and exposure speed ring (4), all of which give on equally correct exposure, The combination most suitable to the character of the object is then chosen and transferred to the speed setting knob on the camera and to the diaphragm setting ring on the lens mount. Rapidly moving objects, for instance, will be taken with a fast shutter speed setting and a small diaphragm numeral, whereas a larger diaphragm numeral and a longer exposure time will be proper if greater depth of field is required. Please note that intermediate values cannot be set an the speed knob of the camera but only on the diaphragm rang of the lens mount.
7. Switch off the metering system by anti-clockwise movement of knob (1) to the red mark.
Pentacon Six ttl prism


Measuring the exposure time
B Measuring with lens at taking aperture

1. Set the film speed as described in Section A, 1
2. By rotating aperture ring (7), move index mark (8) for measuring with lens at taking aperture to coincide with index mark (9), where it clicks in, 3. Cock the camera shutter.
4. Preselect the shutter speed in accordance with exposure conditions (e. g, fast speed far rapidly moving objects) arid rotate ring (4) to bring the speed numeral opposite index mark (8). At the same time, the speed knob of the camera should be set so that the exposure can be made immediately after the meter reading has been taken.
5. Switch on the metering system by clockwise rotation of knob (1): Arrow points to green mark.
6. Direct camera towards object to be photographed so that the important sections of the image appear within the boundary lines of the area (I6). Rotate diaphragm ring on lens mount to center the meter needle to the fixed mark. In this way, the correct aperture/ speed combination is set in the camera and the exposure can be made immediately without any values having is be read off and transferred. Important! On lenses with automatic spring diaphragm (ASB). the manual stop-down lever (17) on the lens has to be depressed during the metering procedure.
7. Switch off the metering system by anti-clockwise movement of knob (1) to the red mark. When measuring with the lens at taking aperture, you also have the possibility of first moving the diaphragm ring on the lens mount to the f number suitable to the exposure conditions -- e. g. 8 -- and then rotating the control knob (3) to center the meter needle to the fixed mark. Also in this case ASB lenses have to be stopped down by means of lever (17). The exposure speed now nearest to the Index mark (8) has to be transferred to the camera. Fine adjustment is made by movement o€ the diaphragm setting ring.
Pentacon Six ttl prism


Pentacon Six ttl prism