in, daylight, so that in special circumstances one may need a larger n-umper of spool charnbers in ord.er to avoid unl"oading them in the darkroom. In such cases, the Leica cartrid.ges of Messrs. Agfa, Gev aert, Hauff, I(odak and Perutz provide a"satisfacto"y *oi'otion. These t4gir films. in special Leica car"tridges for d*yfit3*,supply ligrt-t loadi_ng. Thg cartridg".i. used once only aila is openecl in the darkroom for developing the film. The loading. of !h" Leica cartridges into the camera, and also the unloading, is-done in the sant_e way as a loaded spool chamber Model B. tr'or further details *"6 pages lb-lg: Please note. Leica cameras which are not yet equipped with the lock v2 (see Fig. lJ I must, have this frart rittea if the Leica eart,ridges are io be used.

Fig. I I

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4. Loading of Film Chamber Model B in the darkroom
(In this case darkroom loading film spools are used)
Fig. L2 I{ow the spool chamber Model B should be opened

l. Open spool chamber.

() Remove the cent,re spool from the inner shell. Ta$e the

wrapping off the film.

To this end release with the index finger of the left hand the safety spring B 8 by pulling it backwards (Fig. 12) and turn the inner shell with the right hand at the knob towards the right (clockwise) to the end of the movement,. Then withdraw inner shell.
3. Thread the short tapered end of the film in the slot B 4
of the centre spool BB (emulsion side next to the arrow) itt the direction of the arrow. 1. Wind film on centre spool moderately tight, emulsion side inward, and if possiblC use hand film winder or mechanical winder. Take care Lhat emulsion is not touched.

,. ''""' I,

Fig. T4 5. Introduce film spool int,o the inner shell, milled knob first, the beginning of the filrn lying in the slot'.
6. Put both together int,o the outer shell, superimposing the two slots. Pull out the beginning of the fihn about 2 inches t'hrough the open slots.
Fig 16 7. Close spool chamber by giving the inner shell half a turn to the left, until the safety spring engages at, Z. 8. Pull out, the beginning of the film about, 2 to 3 inches from the closed spool chamber, so that it does not, slip back. 9. If the loaded chamber is not, immediately inserted into the camera it should be kept in the alurninium container after the project,ing piece has been wound around the chamber. L4 Sourced via www.specialoperationsaustralia.com

5. sight-the objec-t through range filder ll, turning focusing lever 17 or the lens mount 22.onril the two imasei coincidE (fuse into one). rJse view-finder 10 to view the"whore field and gently. (not jerkily) release press trutton b. When photographing_ rapidly rnoving objects the range finder should be used as view-finder.
E. Unloading of Camera in subdued daylight
l. Release once again press button wound or not). b (whether knob I is 2. Set reversing lever 6 from A to R. 3. Pull out back-winding knob 12 and turn in direction of arrow until a resistance is felt and wind over this resistance. (This means that the end of the film comes off the spring of the receiving spool.) Give about two more turns lirre tTtm is now all wound back into the spool chamber). 4. Turn swivel 23 of camera lid 13 towards the reft from "closed" t,o "open" and remove camera lid. 5. Pull out spool chamber by means of the milled. knob and keep in aluminium container for developing. 6. The removing. of the film from the spool chamber must g-+ly.be done in_ the darkroom, as desdribed. under B 4, l. The inner spool with the film is then removed and ihe film wound off. l9 Sourced via www.specialoperationsaustralia.com
F. The "Standard" Leisa Camera
The foregoing instruct,ions for the Leica camera Model III a Leica also, except, where reference is apply to the "St,andard" made to the rangefinder and the adjusting dial for the slow speeds. In the " Standard" Letca, the rangefinder is not' coupled with the lens. In the clamp which will be f ound near the viewfinder of the Lerca, a " Standard" special small holder is inserted, in which the short-base rangefinder is fixed horizontallv bry means of a, pin. When it is desired to adjust the time of exposure it is only neFig. 23 cessary, in order to access to the obtain speed dial, to push forward the right-hand end of the rangefinder (see Fig. 24), and after the adjustment has been made to return it to its original position as far as the stop. Now look through the rangefinder and turn the dial until the two images which are visible therein coincide. Read the distance figure, then adjust the index line of the lens focusing mount, to this figure, wherupon the exposure may be made. For shorter distances proceed in the followins manner. Adjust the index of the rangefinder as well as lens rnount right the F.ig. 24 away to the desired distance (for instance, 6 ft. in the case of portraits). Then approach or retire frorn the object until the two images which a,re visible in the finder coincide. rnay also be thab the rangefinder It should be mentioned To do this remove the holder from used in a vertical position. the clarnp. and insert in the latter the flange which is on the eyepiece side.
C. Some additional hints on the use of the Leica
Leitz Trirnrnin$ Ternplate enables the film to be correctly shaped, and its use also results in the saving of film. It is onlv required if film is cut from a long length, or when the exposed part of a filrn has been cut, off , and the rest is to be reloaded into the camera.

Fig. 25. trilrn Trimming Template ('I'rirnming the film for the centre spool)
When using cut lengths of filrns as supplied by various is not necessary. On the other hand, firms, special trirnrning when film strips are cut as required from a long length ) cate must, be taken that the two ends of the film are correctly necessary f or the satisfactory t,rimmed, as this is absolutely rnechanism in the camera. For working of the film winding Template, this purpose it is advisable to use our new Trimming which also rneans a, saving in film as compared with earlier mod.els. At the beginning of the roll of film make the wedge-shaped cut, for the centre spool and rneasure off the required length of film. At the end of this rnake the curved cut, for the receiving
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spool. When doing this there is rnade at the same correct, cut, for the receiving spool'on the remaining the roll. It is therefore not, necessary, as was the our previous Trimming Templates, to trim the next, film taken frorn the rol1, so that in this way about u film are saved. on every strip.
tirne the film on case with length of 4 ins. of
The manipulation of the Trirnming Template is as follows: To t,rim the film for the centre spool, unfold the Trimrning Template and insert, the film, emulsion side underneath, sideways into the narrow slot of the lower plate, so that the end of the film projects stightly beyond the end of the Ternplate. Then close the Ternplate and cut the film along it (see Fig.below).
Fig. 26. Trimming Template (Trimming the film for the receiving

spool)

Except for the end which lies on the lower plate of the in the hollow of the Template, the film remains untouched hand. The end intended for the receiving spool is placed in the unfolded Template, care being taken to see Lhat the emulsion side of the film is again underneath, and that a, small piece projects beyond the end of the Template. The two pins in Then cut along the Template rnust engage in two perforations.

Steady hotd. For slow exposures in the hand it is strongly advised t,o rest, the elbows or at least to lean the body against As the slow speeds some support in order to avoid shaking. a,re preferably used for near objects, t l, and 1/n sec. will give good results with the free hand, also 1/, sec. with surprisingly a very steady hand; for I sec. however, a support, or tripod rs necessary. tr'or convenient followed: For horizontal focusing, the following procedure should be

photographs:

Fig 3l
Rest, camera against cheek, keeping both elbows close to the body - the right hand clasping the c_amera - the right the left index finger on index finger ready on press butt the button of the focusing lever - the left thumb supporting the camera on the side,

For upright

Fig. 32
F'irst Method. Hold carrrera in right hand from underneath - right thumbr stretched over winding knob and resting on press button, must not touch speed dial right thumb elbow middle against against finger body of left forehead. operate focusing lever with index or hand whilst, left thurnbr stead,ies camera
. I The rnethod as set out above obviates shaking with utrnost cert,ainty. Obviously, the thumb rnust release the press button To hold the carnera in this way is particularly when wearing a. hat with a, broad brim. con-

gently. venient

Second

Method.

by many.

method

is also greatlv

favoured

Fig. 32a
R ight hand on top _- right index finger on press button -left index finger a,cbaaLing focusing lever - left thumb supportrng camera. The viewfinder is fitted in the middle of the rangefinder housing. It is a, direct-vision finder, and is to be held close to the eye. The field of view gives the exact size of the photographic image a,L 9-L2 ft.; at infinity rather more is on the negative, and a"t 3-6 ft. rather less. This normal viewfinder is intended for use with the standard lens "Elmar" F/8.s, s crn. also the "rrektor" F'12.5,5 cm and the "Summa,r" }"lz,5 cm. Lenses of other Viewfinder, For foeal length require the use of our Universal which is slipped into the clip on top of the camera. particulars of Universal Viewfinders see page 48.

H. Leica 25O

As shown in the illustration, this model differs in form from the Model III a only by reason of the larger film chambers.

Fig. 33

Each charnber holds a, piece of film of 33 ft. length, is sufficient for rather more than 250 pictures.

tr'ig. 34

The manipulation differs in the following points:

of the Model

a only
Loading the filrn charnbers: As the Leica 250 has a film chamber at both ends, two knobs are provided. for locking the base cover plate, which must first of all be opened. One of the chambers is loaded with film in the darkroom in the usual way, and the projecting piece of filrn is trimmed with a special template, which conforms with the length of the film track in the camera. The beginning of the film is now fastened under the spring of the second spool chamber, the long uncut edge of the film against the spool disc with knob. This chamber also js then closed in the usual way. The two closed chambers are now placed in the camera, so that the film slips in the narrow guide slots (see Fig. B4). Care must be taken that the knob on the underside of each film chamber snaps into position, by gently turning the chamber. This is easily effected, because the screws which hold the spring closing the chamber have specially high heads, which compel one to insert the chambers in approximately the right position. The base cover plate can only be closed if the two film chambers are correctly placed. When the two locks are closed, the two chambers open together. Finally, the film is tightened by gently turning the back winding knob as well as the milled disc on top of the winding knob in the direction of the arrow. The film'is not be too inconvenient The spool wound back on account may after exposure, as this would of the length of the film. in a dull light.

chambers

be changed
If it is desired to take out a piece of filrn which is not entirely exposed, before opening the base cover plate the film must, be slackened a little by turning the above mentioned milled disc in the opposite direction to the arrow. After removing the cover, both chambers may then be taken out or the film may be cut with the cutting knife supplied and the winding-on spool only, which contains the exposed piece of film, taken out. It should be observed that when fastening the filrn in chamber, the end should not, be doubled- over, as otherwise film cannot, come out of the chamber after exposure. this been done accidentally, before opening the camera film must be loosened in the manner described above both chambers are than removed and the fastened end of film released. the the Has the and the

I. Accessories for single exposures 1. A special ac,sessory single exposures for
with dark slide and focusing screen The device consists of a black lacquered light metal body, in the back of which is the focusing screen or darkslide, the Leica lens being screwed in in front. One of the well known
trig. 35 a Leica viewfinders can be fitted on top; on the side and underneath the housing bushes are provided for upright or horizonhal pictures on a, tripod.

Fig. 35b

The body of the device does not, contain a, shutter. An Ibsor shutter is provided which is fitted on to the lens and which allows of instantaneous exposures from L-, lrrb sec. and tirne exposures. fits This shutter can be supplied in two sizes. The srnaller one the lenses "Leibz-Elmar" F f 3.5, 3.5 cm. (wide angle),
"Leitz-Elmar" F/3.5, 5 cm. (standard) and "Leitz-Elmar" F/6.3, I0.5 cm. The larger one fits all lenses except the "Leitz-Elmar" 13.5 cm., "Leitz-Hektor" 7.3cm. and 13.5 cm. "Leitz-Thambar" 9 cm. and "Leitz-Telyt" 20 cm. For photomicrographs in conjunction with our Micro Attachment, the shutter is not used, as this attachment contains a shutter. The codeword for the device with the small Ibsor shutter is "Oleyo", that for the device with the large shutter "Oligo". Only screw-in filters can be used with this devico. The manipulation of the device is simple in the extreme. After removing the cover plate of the darkslide in the darkroom, it is loaded with a piece of film of standard width and about 40 mm. Iong, cut from a roll of standard cinematograph film (or from a film in a Leica film chamber). The width of the slide is exactly 40 mm., and can therefore be used as a guide for the length of the piece of film to be out. The cover plate is then pressed back into position, care being taken to see that the film in bhe slide is not pinched. The slide is then ready for use. Before making the exposure, the focusins screen is placed in the groove in the slide, where it is held by a spring, and the lens is screwed in in front. The subject is posed and focused on the ground glass. The diaphragm is then set to the desired aperture and the shutter slipped on. To make the exposure, the darkslide is inserted in place of the focusing screen. Bv simultaneously pressing gently on the catch, both parts can tre inserted or removed conveniently and without shaking. If the placing of the object has been disturbed through incorrect manipulation, a glance through the finder is sufficient to put, this right. The sheath of the slide must, of course be drawn before the exposure.

The 'oLeitz-Eknar" F f 4.5 r 3.5 crn. focus is specially designed as a snapshot lens,. as on account, of its shorlt,focai lenglh and reduced aperture it gives a great depth of focus. fte lens is not coupled with- the rangefiqdgr' and is primarily intended for use-with the "Standard." Leica. It can be set t"o only four fixed distances, 6 ft., g ft., 30 ft. and infinitv. The "Leitz-Elrnar" Lens I.16.3, l0.5crn. f6cus is a relatively srnall an4 light distance lens, weighing about 7 ozs., and is particularly fav^oured by mountaineersl rtslesser aperture is in rnost cases perfectly sufficient, as when p^hotogiaphing distant views one rnostly has to stop down to 6]8 in any case, in order to overcome unsharpness which may arise lue to distant ltaze. Those who demahd a greater aperture (implving increased weight and volume) will cLoose on6 of the folfo#in[ distance lense-s. The "Leitz-Eknar" Lenses F l!,9 crn. focus and F l4.bl 13.5 crn. focus are rnainly used for photographing distani views, but they are also v'ery suitable^ for piort*raits"when it is desired to fill the whole negative with hbad or head. and shoulders without the necessity of getting too close to the subject. - Owing to the increased rvorking-distance thev are frequently used to avoid distortion of profortion. These ienses are used with our universal view-finders (see page 4b). The 9 cm. i*rgg angle for Leica negatives of the "Leitz.El;rar,,' lens is 27o and of the "Leitz-Elmar" lens lB.5 cm. lg0. The "LeitzF.lrrna"t:" lens 13.5 cm. is approximately bt' long and weighs l43lo ozs., whilst the "Leiii Elmar','l6ns gcml measures only 3" and- weighs l0 ozs. Where it is required, therefore, to have a distance lens of fairlv wide apertu-re but small size and weight, the latter lens will be pr6ferred. The "Leitz-Hektor" I.14.5, 13.5. crn covlers the same range of appiication as the "LeitzF.lrnar" l3.b cm., but surpas!91 the latter in that it has a higher resolving power. When working with these long Iocal length leirses it is particularly i.mpor_ta1t -to keep the damera stea-dy. When using the 13.5 cm. lens the left hand should hold the lehs mount frori below, in rifle fashion, whilst the right hand should control the -in release. This should not be done jerks but by gradually prssure as -when working the trigger of a rJfle. Pre?pplying ferably a tripod stand should be us6d with tiiis lens, in order to avoid blurred pictures. The "Leitz-Hektor" lens F.l2.Sr b crn. focus meets the wishes of those Leica p-hot-ographerswho desire to obtain snap. shots under unfavourable lighfing conditions both out of dodrs and indoors. The "Leitz-Ilektoi" lens is not a soft picture producer like many other lenses of this aperture, alth6ugh it naturally does not _quite attain the samd crisp definitioi as the "Leitz-Elmar" lens.

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The tubular socket, of the "LetLz-Irektor" b cm. lens is pulled o1r! for Photographing in the same way as the standarcl lens and locked in a bayonel catch hry turniirg it to the riglr t (clockwise). When the camera is not in use t[e lens sockef is turned to the left and pushed into the camera body.
tr'ig. 38 The "Leitz-Hektor"J'/ 6.3, 2 r8crar.focus, is purely a wideangle lens with ?n alqle of i1n*g^"9f,760. Even u,t tti" rerrlarkably large a,perture for this a^ngle.1. n'/0.? it glv_esabsolutety sharfi -We negatives entirely free from distortion. wish to mentioir particularly that this lens also is_ coupled. with the rangefinder, which has not been done befofe with lenses of tllis fo-ca-llength. The relativ"l-y. grea_t light t,ransmitting capacity of the lens permits shori instantaneous exposures "f 1ntFi^g even under unfavourable lighting conditions. The "Leitz-Surnrna;t" F 12, b crn. is a first-class universal lens. Even a,t, full aperture, this lens gives critical definition right t9 t4" very. corners. The partidrlarly good chromatic correct'ion is especially important-in conjun"tidrt with the use of modern panchromatic f-ilms. The construction of this lens is such that pictures taken with it have a definite plastic effect. The lens is therefore equally suitable for all kind's of artificial light and Press photography a,sfor general amateur photographt.
The "Leitz-Summar" is obtainable in collapsible or noncollapsible mount. The "collapsible T,ettz-Surnma,r" has arrows at right angles to each other on the lens socket-tube, for use when pulting out
trig. 39a. "Leitz-Elmar" lens F/6.3, I0.5 cm. focus

and locking socket-tube,

Fig. b. "Leit z-Ifektor " lens F/1.9, 7.3 cm. focus
,rLeitz-O*i+g to its great, light t,ransmitting capacity, the IIektor" lens Ff 1.9, T.3 cm. is of particirlar importance for t-bu Press.photggrapher and where a longer focui for greater dist'ances is desirabie. At full aperture atf,ention must 5e paid
the lens. On the ring which encircles the lens there is a, short line.- This line must be flush with the arrow in the longitudinal direction of the socket-tube. The lens can then kre drawn out, completely, and the second arrow then appears horizontally on the socket-tube (see Fig. 39c), indicating the direction in which to lock the lens. The lens is simply turned right round to the stop and is then securely locked. The aperture figures can be conveniently read from above. When locking the lens, hold only the first milled ring, without touching the milled ring behind, which Fig.39 c. "Summar"F I2, serves for adjusting the aperture. 5cm., collapsible mount The aperture should be set only after the lens has been locked.

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L. Accessories to the Leisa Leitz Angular View-Finder
for the Leica Carnera with 5 crn. Lens The Leitz Angular View-Finder ("Wintu") enables one to make exposures without a,ttracting attention as the sighting
device lies at, right angles to the ob ject to be photo graphed: is, that the photograph is taken as it were "rottnd the cofr1g1"r. The forked bracket of the angularviewfinder is slipped into the clip on top of the camera and the small prism attached to the finder Fis.42. The Anqular View-Finder is switched in front of the eyepiece of the range finder (see trig.42).The carnera is held during the in Fig. a3. Focusing bry means of the exposure as illustrated reflecting prism of the angular view-finder is sirnplified if the object is first sighted in the eyepiece of the finder. The angular view-finder can only be used with the Leica camera and Leica lenses of 5 crn. focal Iength. The image appears right and left reversed. Fig. a3" Ifow to use the Angular View-Finder
Leitz Universal View-Finders
for the Leica camera with interchangeable lenses When using the Lerca camera with interchangeable lenses, the various fields covered by the different, Ienses are det,errnined with the aid of special optical viewfinders which slip in the clip on top of the camera body.
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The Large Universal Finder "Vidom"
for all Leica lenses This finder contains an oblong diaphragm which is adjustable in size. By rneans of a rnilled ring ttie field of view is reduced. or increased. The proportion of the sides remains always 2: 3. The milled ring is engraved with the various focal lengths of the Leica lenses. The diaphragm shows, therefore, only the field of that lens f or the focal length of which the index line has breen set, and this for distances from 30 feet to inf inity ( oo). A second shorter index line close to the other is referred to when taking close-ups, i. e. for distances from 3.5 to 6 feet. It gives the re F.ig. 44 duced field obtained at The Large Universal View-Finder these short ranges with aII Leica lenses, with the exception of the wide-angle lens. tr'or distances betw-een 9 and 30 feet the milled ring is best, set between the two index lines. For compensation of the parallax between finder and lens (displacement, of bot,h optical axes) this view-finder is fitted with a, cam and lever rnotion for tilting the finder. By this it is ensured that an object sighted through affrargement the cent,re of the finder ?ppgars really in the centre of the pnotograph. The parallactic effect is not noticeahrle at distances over L2 f-eeb. tr'or shorter distances, however, it has to be compensated for by tilting the finder. This is done with the small lever underneath the eyepiece which is marked with figures for the respective short dist,ances and for infinity (o ). When taking _a portra,tt, for instance, after having focused the camera, the distance is read off at the focusing scale of the Iens, and the parallax lever set accordingly. When taking a portra,tt, for instance, after having focused the camera, the distance is read off at the focusing scale of the lens and the small index line of the milled ring set to the focal length of the lens used; Iastly the parallax lever is set according to the distance read off tr'or changing over from horizontal to upright pictures and vice versa, see page 48.

for the Leica camera This finder can be highly recommended, espocially for sports photography and for exposures from aeroplanes. Its most noteworthy feature is that it, covers all possibilities of use, because it is not only of service for the standard lens of 5 cm. focus, but also shows the ansle of field for the 3.5 cm. and 9 cm. "Leitz-Elmar" lenses, as well as the 7.3 cm. "LeitzIfektor" lens. For this purpose the image frame can be rotated throuEh l80o against two stops. The noriral position as shown in the illustration indicates the fields of the 5 cm. and 9 cm. lenses, while the field of the 3.5 and 7.3 cm. lenses is shown when the frame is swung round, owing to its eccentric motion. By fixing a special mask on the front side, it also serves in its normal Fig. 46 posilion to give the field of the 13.5 cm. lenses and in the opposite position, that of the 10.5 cm. lenses. So as to facilitate t'he exact alignment of the narrow angle of view when the long focus lenses of 10.5 cm. and 13.5 cm. focus a,re used, a pin-hole can be clipped in position in front of the rear sighting aperture. This pin-hole can, however, not, be used with the other lenses, as it would cause the field of view to appear' too much enlarged. Parallax in the case of close-ups can be compensated for by vertical displacement, of the back sight of the finder. To this purpose it, is engraved with notations o, 6 ft. and 3.5 ft. When using the lenses of 3.5 to 9 cm. focus care should be taken to look straight through the frame of the finder; this ensures the exact coincidence of the centre of the field and its boundaries with those of the nesative on the film. The sighting frame is alwaSrsheld close to ihe eye. The Frame Finder can be collapsed when not, in use. 49 Sourced via www.specialoperationsaustralia.com

Le itz Reflecting Finder

for the Leica camera Contrary to the principle of direct vision at eye-level embodied in all other Leica viewfinders (normal, Universal and Angular Finders), the R,eflecting Finder is constructed on the principle of the well-known reflect,ing finders. The image is consequently not' viewed a,t, eye-level but from a, position
about 8 inches above the finder. This is found finder mainly convenient, where it is required to photograph from a lower position, as, for instance, when photographing children, small animals etc. The finder consists of a housing a socontaining "pent,a" called Fig. 47 prism in conjuncon the Leica The Reflectine View-Finder tion with a, negative lens (Newton results in a very clear, bright finder). This novel combination image. and sharply-defined To indicat'e the size of field for honzorft,a,I or vert,ical photoThe graphs.the four corners are blocked out' in the yso{-way. image is uprigh! and correct, as to_right ?ttd left. The field of to that of the Leica lenses of 5 cm. focal vrew corresponds length and Leica negative size 24 X 36 mm. On special request this finder can also be supplied equipped it to be used with the front lens, enabling with a, negative 3.5 cm. wide angle lens. "Leitz-Elmar" The finder has engraved on top small cross-lines and in front a small circle. should be done with one eye only, Sighting and the cross-lines should appear in the centre of the cirele so as to ensure that the camera is not' slant'ing. A special clip fitted to the side of the finder may accomodate a case level. The R,eflecting Finder has t'wo fixing flanges for horizont,al and vertical pictures and is slipped into the clip on top of the camera body.

The distances are measured from the back of the oamera (plane of the film) to the object. It may be observed here that 5 cm. lenses of the Leica camera ("Leitrz-Elmar", "Leibz-Hektor" and "Leitz-Summar" ) without supplementary lens render it practicable to take objects at a distance of Stlzft. and in these circumstances reduce the size of g,n object rneasuring 26 x ITLln ins. to one-eighteenth its original size. By enlarging the negative obtained with the front lens in use, a picture can be made to show the object in natural size and, where the front lens No. 3 has been used, it can even be enlarged beyond natural size. Detailed particulars respecting the setting of the c&mera lens by its helical focusing riount,-the distance- and practicable size of the object, as well as the resulting reduction-and depth ^the of focus, may be found from the "Ta61es for Use with Leica C&mera" compiled by us. The supplementary front lenses Nos. I and 2 for the "LertzElmar" lens are available for use at full aperture for snapshots. \4lhen using them for copying worli they should 6e stopped down. In particular, it is advisable in the case of the No. 3 front lens always to stop down to at least F/6.3 in view of the very small depth of focus. The front lenses to the "Leitz-Hektor" 5 cm. lens, howover, require a restricted use of the iris diaphragm. For further particulars please refer to the "Tables for-Ilse-with the Leica C&mer&". The supplelnentary front lenses to the "Loitz-Hektor" may also be used with an intermediate ring "Vorgi" for the "LeitzSumm&r" 5 cm. lens, while in the same manner the supplementary front lenses to the "Leitz-Elm&r" m&y be used. witn an inteimediate ring "Vmcoo". It is obvioos ihu,t the somewhat smaller diameter of the "Leitz-Elmar" and "LeitzIilektor" front lenses necessitates stopping down t,o a certain extent, but this is in any case advisakjie in this kind of work. The exposure is the same, whether one photographs the same object with the "Leitz-Elmar" lens aloire at-a distance of 3.5ft. or with a supplementary front lens No. I a,t,23Lfnins., or with the supplementary front lens No. 2 at I6L l" ins. or with the front lens No. 3 at 1011/ruins. To enable one to use yellow filters in conjunction with the front lenses, we supply an intermediate collar ("Firgi"). Particulars of reproduction. work, for which "the suppl.ementary front lenses are especiaily well suited, are given in our catalogue on reproduction devices in conjunction with the Leica. Our catalogrre "Auxiliary Reproduction Devices" deals at length with the use of these froht lenses.
The yellow in conjunction instance, they

r.6.2.0 r.4.2.0

1. 2. 1. 3 I. 6. 1. 81. 6. 2. 0 t. 2 I. 1.t. 3 1. 2. 1. 8. 9. 2. 51. 2.r.3 r t.7.2.52.5.3.2

1.3.2.0

t.6.2.2 1.1 1.2.1.8.2.2.1.1 r. 6. 2. 5 r. 2. 1. 8 1. 6. 2. 5r. 6. 2. 5 1.2.1.8 2.2.,5.0.6.2.0 1. t.2.r.6 1.3.1.8.9.3.1 1. 2. 3. 4. 0r. 7. 2. 3 1. 3. 1. 61. 4. 1. 8. 4. 2. 02. 0. 2. 71. 2. 1. 6 L 2. 5. 3. 9. 8. 2. 5. 2. 1. 8 1. 6. 1. 8. 6. 2. 02. 2. 2. 5t. 2. L. 1 1
The figSrres given in the table under "sunlight" factors are correct for white light, e. g. blue sky with white clouds. The ex-posgre shoulcl be increased by approximately one half when the light is dark blue, e. g. in summer from about ll a.m. to 2 p.m. (blue sky without any noteworthy clouds). 55 Sourced via www.specialoperationsaustralia.com
The use of dense (i. e. dark) filters is not to be recommended. since.they c_ause blue to appear too dark and green and yelow too light. In.practical.p-hbtograpk_ry,such pf,otographJ have a pronouncedly overfiltered and consequently- rinnatural -choose appearance. care must alwayp be taken to the density of the filter one uses so that it may suit the subiect, the fitm "This m3,terial, the time of day and the illumination. method will be found to give the best results as far as the correct rendering of colours is concerned. rt should be noted that.
Lens hoocl Yellow fllter Intermecliate collar Supplementary front lens Leica lens

Fig'5I' t'*,l;Jixl'H

attachments :11#i j;:i'
according as the film is more correctly sensitised as to colour -correspondingly rendering, the filter in use can be lighter; for instance, B" Iighter filter wiII be used ri'ith palbtrroinatic ^same film than with oithochromatic film and in the wav. a lighter filter will be chosen for the latter when it is sensit"ised especially for yellow-green. Another factor to be borne Inore in mind is that in the mornlng and evening the light from the sky- contaiqq r great-er proportion of yeilow rais and only little violet light,-so that^at lhese times "u, Iieht"" filt.r. or even no filter at all should be used. rn the midAle of the dav. on the contrary, the light is bluer and necessitates u, "o-e"#hu,t donser filter. rn the same manner, a deep blue skv necessitates a donser filter than a sky with highly rbflecting *ttitu clouds.
_ There is, however, yet another reason whv one should abstain from the use of- too dense a filter, besihes the effect of over-filtration referred to above. rn unfavourable circumstances a dense yellow or green filter can impair the absolute sharpness.of the negatives, especially in tire case of films with a thick coating- of emulsi-on. The plane paraltel finish of good filters_ (w_rich, one might say, i-s almo'st carried, to excegp)_ certainly obviates a distortiori, but the difraction of the.light in a.thick coating of emulsion cannot fail to causo deterioration in tEe sharpness if the blue rays are l.slight drsproportronately cut, out. This is due to the fact th-at the short, wave blue and violet rays forrn the image on the surface of the emulsion; they hardly penetrate the" interior of the emulsion and can cons-equenttjr n9-t be diffused. Ravs of longer wavelengt\ (yellow and abov-e all red rays) penetiate or,. Ihe -emrirsion other hand compa.rativgty far into the and suffer difraftion; this difractioh increases proportionately to trre. depth _of the emulsion. The surface lmage rn consequence somewhat, ippairea in_its sharpness bylnis ls diffused irnag" rormed rnsrd.e the emulsion. The denser the yellow filter or lFg g"ugn filter, the more blue rays are cut but, and other things being equal, the greater is ihe loss in sharpness. This loss of sharpness must, of course not be exaggerated. rt can in fact be.completely overlooked in the case"6f films having a very thin co-ating of emulsion. tr'or use with the Leica camera with focar plane shutter the y-ellow_filters- are usually sup_plied in slip-on'-or*t. rig.ti how,they are att-acheidl either arole or in -onjunc?ion "q9y" wrth a supplementary front lens or lens hood. For the simultaneous use of a supplementa,ry front lens and a yellow filter an uintermediate ring 1s require-d, (.,Firgi,,). ^ rf desired,_yellow filters can be supplied in screw-in mounts for use with the focal plans shutter_ caidera. The iris diaphragm in this case is actuat-ed directly, but the yellow filter cannot then be used in combination with the frdnt lens. For the two lenses "Leitz-Elmar', 814.5, l3.bcm. focal length, and ''f.eitz-I{ektor', Ff 2.5, fodal length, the filters { are supplied in slip-on mounts only"*. (see Leica Eatalogue). yellow The Graduated Filter. \4rhen photographing scenes-with a particularly bright background aria a dE"li fo"el ground, we _recommend using the graduated vellow filter to -This a'oid partial over-expo_sure.fi-iter is supplied in a fixed slip-on m:ynt_to fit^all Leica cameras haviii'g io-"i-pr"ttu shutter. The dividing line of the filter is in tlie "centre.'care must, always, be taken to ensure that the arrow engraved. on the outer edge^of the mount, lies on top. The filtJr doubles normal time of exposure.

vice versa the graduated yellow filter can also be used for seenes with a particularly bright foreground (snow scenes etc.). In this case the arrow- engri,ved on"the mount, must lie underneath. Green fllter. All panchromatic negative material to be had on the market and destined for use rnlitn tne Leica presents a gap in the scale of reproduction in the green sectioir of the spectrum as comp-a_red its sensitivity to red and blue-violet. to A suitable green filter remedies this defect. The filter factors for our green filter are given in the table on pages bg and 5g. - The new panchromatic films with reclucecl sensitivity to red necessitate a filter which transrnits chiefry yellow and gieen; our yellow filter No. 0 may be used for tiiJ purpose. Red fil.ters. They are used in conjunction with infra-red film, which is also sensitive to infra-r"ed rays in addition to the range of a visible spectrum. The use of this filter allows only the visible red-and a portion of the (invisible) infra-red ravs to be used for the forrnation of the image, since'it absorbs yellow, green and blue almost entirelv. TYhe peculiar effect of these infra-red photograph-s is of less"importairce for general amateur photography than for special sci^entific purposes. , For example,- it. is-possible with the help of infra-recl photograpfy t" obt_ain clear photographs of mountains, scenery gJ.to.wts_throygh the mist aha tog piesent in the atmosphere"; this is of special importance in the 6ase of aerial photoeiaphv. -to-a ln every case, however, the infra-red photograp6 diffeis greater or a lesser degree from the image seen ri'itkithe naked eye. \4lhen the sky is clear_ _and the sun is shining brightly, the red filter causes the blue of the sky to app"ear u''t""tli objects in the scenery (foliage and buildin[s) refl6"1 th" infrarays strongly and consequently apfear bright in the "gd picture. Taken together, the general eff-ect is o.e- of a night photograplr.It is, however, not exactly similar to a ni[ht photograph-, in that the latter would ca"use the lands"u,p""to appear dark. A correct, use of infra-red film can, however, be of adva,ntage for reproducing certain features of anatomical speclmens, reproductions of paintings, etc. The helical focusing'mounts of all Leica lenses now bear a second index mark, iridicated by R, which serves for focusing y.lgr taking infra-red photographs. The object is focuseE drtterently accordin_g_ whether the lens is coupled with the to llngefinde-r.(Lei_cas II and III, Leica 280) or not-(Leica I and "Standard"). When the lens is not coupled witL the rangefinder the distance is read off on the ranelefinder scale and t"he lens sot to that distance by means of th6 index R,. When the lons is coupled and in th-e case of the accessory for single 58 Sourced via www.specialoperationsaustralia.com