Petits Cliches et Grandes Epreuves
Contents
- Bernard and Touchebeuf's preface declares the book a practical manual rather than a scientific treatise, written for the touring cyclist who is already an amateur photographer. They set out their governing creed — "faire petit pour obtenir grand" (shoot small negatives and enlarge them) — arguing that enlargement rescues the composition and tonal softness that tiny contact prints destroy.
- Opening of the First Part: gelatino-bromide of silver has driven out every older negative process among amateurs thanks to its speed and keeping qualities, but its visible grain sets a practical ceiling on enlargement. The authors conclude that medium-speed emulsions should be preferred whenever instantaneity is not essential, and that a negative made for later enlargement must be better than any other.
- Fixes the sensible limit of enlargement at two to two and a half diameters and prints a table of the standard plate sizes (4½×6, 6½×9, 9×12, 13×18) against their 2×, 2½×, 3× and 4× enlargements. Cost, the rarity of subjects worth enlarging, and normal viewing distance argue for 24×30 as the largest useful print, and so for 6½×9 or preferably 9×12 as the cyclist's negative format.
- Opens the survey of cameras by refusing to catalogue every model on the market, each season bringing a new one differing only in detail. What the serious amateur needs is a robust, precise instrument with a high-efficiency lens and a shutter whose slowest speed is genuinely slow enough for hand-held work under heavy foliage.
- The binocular-form hand camera, revived by the engineer Carpentier in 4.5×6 and 6.5×9, is now made by Zion, Joux (the Sténo-jumelle), Mackenstein and Roussel, and all of them satisfied the authors. Three recommendations follow: a clear reticulated finder, a detachable magazine so spare loaded magazines can be carried, and a detachable lens.
- Describes H. Mackenstein's 9×12 photo-jumelle — a pyramidal morocco-covered wooden body whose magazine can be swapped for a ground glass so the camera works on a tripod. Carrying spare magazines spares the touring cyclist the hunt for a darkroom, a problem the Touring-Club de France has still not solved along the roads of the Alps.
- T. Roussel's Stella jumelle differs from the Mackenstein only in its Hanau-Richard-derived drawer magazine of twelve sheet-metal plate holders and in placing the shutter behind the lens, so that the lens can be detached and reused for enlarging the very negatives it made. A red window reads the number on the last plate holder and serves as an exposure counter.
- Traces the folding hand camera from the winged ("à ailettes") pattern of Dubroni, Arwing and Dr Candez, re-invented by Schew, whose front standard worked loose in use, to the modern folding camera with double rising-and-crossing front, spirit levels, Congress-thread tripod bushes, and a choice of double dark slides or a twelve-plate magazine back.
- The book's cycling chapter proper. The authors address the rider who already knows photography and want only to give him the precautions peculiar to making negatives on the road that are destined for enlargement.
- Practical kit and technique for the touring cyclist: a tricycle will carry anything (one of the authors travelled with a 24×30 outfit), while on a bicycle a photo-jumelle is the sensible load, and M. Tennevie's Touring-Club spring-steel luggage carrier clamps to the head tube and takes a 13×18 folding camera. It advises an aluminium five-section tripod folding to 0.45 m and weighing 650 g, a red paper lantern, orthochromatic plates and a yellow screen for glacier-and-cloud subjects, and — emphatically — not developing while travelling, since hotel-room water and improvised apparatus ruin the plates, which keep for months after exposure.
- A short chapter on taste, urging study of the masters of painting and drawing rather than any formula: the parts of a photograph should not all be equally sharp, and only sustained personal observation will give a print the artistic stamp so rare among users of the dark chamber.
- Development is called the single most important photographic operation, and handing one's negatives to a trade developer "a photographic crime", since only the person who chose the effect can interpret it. The chapter rejects automatic single-solution baths and gives three specimen developers of quite different kinds: M. Forestier's rapid one-solution hydroquinone-paramidophenol formula, a rational multi-solution pyrogallic-acid bath, and an iconogen/pyro slow bath for developing many plates together.
- Two warnings only: add 2–5 per cent liquid sodium bisulphite to keep the hypo bath clear and stop the gelatine staining, and do not lift negatives from the fixer as soon as the white backing clears. Yellowing is blamed as often on incomplete fixing as on bad washing, and washing should run two or three hours, longer in winter.
- Closes the First Part with a plea to work knowingly rather than by recipe. The photographic formulary is inexhaustibly rich — one wag combined nearly every reducer into a concoction he called "omnidéveloppol" — but the moral is to decide what result is wanted and then choose the means.
- Opens the Second Part, on making the positive. The authors will review the various enlarging apparatus and methods but describe only one print developer in detail, and have chosen gelatino-bromide paper because its sensitivity alone allows direct enlargement by ordinary artificial light.
- Argues that bromide paper is what will lift the amateur off the beaten track of photography, needing only an exposure to any light source and a rapid development, and making enjoyable work of bad weather and long winter evenings.
- Amid the classic brands — Lamy, Lumière, Eastman — the advice is to choose one and stay with it. A. Lumière et ses Fils' three grades are taken as the type: A matt and C glossy for contact printing, B made expressly for enlargement, and the coefficients given show C needs three and a half times B's exposure.
- Divides enlarging apparatus into five categories: improvised use of equipment already owned, projection or enlarging lanterns, three-body cameras, solar and diffused-light apparatus, and the enlarging cones sold as automatic apparatus.
- Two window methods needing no purchase at all. In the first a 6.5×9 negative is taped inverted into a cardboard mask at the window and enlarged onto bromide paper in an ordinary 13×18 camera fitted with a short-focus lens, a black cloth on two battens excluding stray light. The second darkens the room entirely, works by red light, and allows very long-focus lenses and far bigger prints.
- The enlarging lantern is the common magic lantern: a condenser of two plano-convex lenses face to face, the negative against it, a portrait lens in front. A 15 cm condenser suiting 9×12 is recommended over the bulky 25 cm size, the lantern should have a bellows front with rising and cross movements, and the authors fix the easel to the wall and move the lantern rather than trust a rolling stand.
- A detailed specification for the three-body copying camera in 24×30 — negative carrier with hinged ground glass and shutter flap at the front, interchangeable lens board in the middle, double swing back at the rear to correct the converging verticals hand cameras produce, all on a rack-and-pinion carriage. The authors describe the modifications long practice led them to have made by their cabinetmaker, including a detachable front so the camera can be used normally.
- Introduces the solar and diffused-light enlargers, mentioned mainly for completeness since even professionals have all but abandoned them.
- The solar enlarger: a south-facing aperture holding a condenser, an external silvered mirror at 45° driven by clockwork as a heliostat to follow the sun, and behind it a bellows box carrying an unvarnished collodion negative. A full 57×44 sheet needed about forty minutes' exposure; bulk, complication and price confined these outfits to professionals.
- The surviving variant dispenses with the condenser and faces the studio north, enlarging on bromide paper by diffused daylight through a 23 cm aperture, with an opal glass and a white reflector outside. The easel runs on rails, and a hinged board that drops down like a table lets the paper be pinned in place without disturbing the focus.
- The enlarging cone: a truncated-pyramid box with the paper below and the lens above, a second box over it carrying the negative, exposed to diffused daylight at a fixed focus. Sold as ampliateurs, amplificateurs-réducteurs and automatic apparatus, the better ones take 6.5×9 to 13×18 or 18×24 and 9×12 to 18×24 or 24×30; the authors recommend one for the amateur short of time, their only reproach being that it makes him lazy.
- Quoting the Abbé Moigno that "the lens is the soul of photography", the chapter advises against risking a good lens in the heat of a lantern and lays down the governing rule: the enlarging lens must cover the negative without recourse to very small stops, which would only lengthen the exposure.
- Opens the chapter on exposure and light sources together, since the second governs the first, and warns that nothing but practice can teach exposure.
- Exposure depends on the light source, its distance (falling off as the inverse square) and the density of the negative. The recommended method is a stepped test strip masked in five-second stages until one develops fully in thirty to forty seconds; a table of stop values and an extract from Debenham's table relating exposure to degree of magnification are given, worked through as a simple rule of three.
- Lays down as an absolute principle that any artificial light beats daylight for enlarging, because it can be held constant or varied at will, whereas with daylight the operator remains "the servile slave of the sky" and must re-find his exposure from one minute to the next.
- Paraffin is the commonest illuminant, but the multi-wick projection lamp is condemned outright for enlarging because its several flames cannot be centred and light the field unevenly. A plain round-burner lamp with a glass chimney is wanted, the best oil, a little camphor added to raise its carbon content, or the Auer intensive-burning system.
- Coal gas was until recently almost useless behind a condenser for want of actinism, but the Auer mantle has changed that: the No. 3 burner gives about 125 candles for projection and the No. 1 and No. 2 burners 43 and 60 candles, with quite acceptable exposures for enlarging.
- The limelight blowpipe: open the coal-gas tap, let the flame heat the lime cylinder, then admit oxygen carefully until a sharp dart of flame brings the lime to dazzling white. The light is very beautiful, very steady and of practically constant intensity for a given jet.
- Oxy-ether generators give all the qualities of limelight without needing a coal-gas supply, but the authors' personal impression is that the light is far from safe and should be left to experienced practitioners. Like limelight and the arc it is reserved for projection, very large amplifications and very hard negatives, being too powerful for everyday enlarging.
- Covers both the arc — struck between two carbons held by a hand or automatic regulator, the positive carbon hollowing into a crater that must be slightly offset so it throws its light on the condenser — and the ordinary frosted incandescent lamp, for which a short doubled filament, a slightly under-rated voltage on the usual 110-volt mains and a home-made resistance are advised.
- Magnesium ribbon or powder, burnt in special lamps, can serve with the three-body camera, but the authors think it impractical: costly, very smoky, and in powder form so hard to regulate that the exposure becomes a lottery. If used at all, the flash should be fired behind a transparent screen well away from the negative, two or three flashes replacing one if needed.
- Discovered by Davy in 1836 and made practical by M. Moissan's recent work on calcium carbide, acetylene is entering a new phase, with generators already on sale and carbide factories multiplying. Trials with several burners grouped together gave 150 to 250 candles with no attendance at all, against 80 to 100 for a fussy multi-wick paraffin lamp.
- Ranks the sources for enlarging as electricity, then acetylene, gas and paraffin, and explains centring against the condenser: a uniform red fringe at the edge of the light cone means the source is too far, blue that it is too near, and a fringe on one side only that it is off the optical axis. For apparatus without a condenser, lighting by reflection from a white screen about a metre away — better still from two equal lamps — is recommended, which also lets the ground glass be dispensed with.
- Focusing for enlargement is complicated by the need to set the bellows extension for a chosen degree of amplification, so the focal length must be known; the authors skip nodal points and calculation in favour of a simple measurement good enough for the amateur's rough sums.
- A table giving, for enlargements of 1 to 5 diameters, the subject-to-lens distance, the lens-to-image distance and the total extension in terms of the focal length F. A worked example follows: a 15 cm lens enlarging three times needs 20 cm in front and 60 cm behind, 80 cm of total extension. The authors add Vanazzi's trick of substituting a glass covered with tulle for the negative when making the final focus.
- A full-page extract from Secrétan's table, printed sideways, giving image and subject distances for focal lengths from 8 to 40 cm at magnifications from 1× to 5×; the upper figure in each cell is the image distance and the lower the subject distance, reversed for reduction. Millimetres are omitted, so precise focusing is still required.
- Developing the positive is far less delicate than developing the negative — with a good negative it becomes a matter of manipulation — so the chapter concentrates on operating practice rather than chemistry.
- Gives the Lumière house formula as the type: 1000 cc water, 20 g anhydrous sodium sulphite, 5 g diamidophenol and 5 cc of 10 per cent potassium bromide. Its lack of alkali avoids many operating accidents, but the bath must be mixed only at the moment of use and the diamidophenol added to already-sulphited water or it oxidises at once.
- The bath must be fresh and clear and thrown away at the first sign of oxidation; 100–125 cc will serve about eight 13×18 sheets developed without interruption. It warns of the constant tendency to judge prints too light under strong safelight and too dark under weak, so a regular darkroom light should be settled on, and gives the Lumière fixing bath (1000 cc water, 200 g hypo, 10 g crystallised bisulphite, 20 g alum, the alum dissolved separately).
- Lists the four vessels to set out beforehand — rinsing tank, developing dish, fixing dish and a good washer — and describes soaking the exposed sheet before development so it lies flat and the developer spreads evenly. The operator should count the seconds aloud: a print fully out in under twenty-five to thirty seconds was over-exposed, and the correct moment to withdraw is about twice the time at which the first traces of the image appeared.
- Withdrawal and immersion must follow each other quickly for over-exposed prints, or the developer goes on working; but correctly exposed prints reaching full effect in thirty to forty seconds gain in the depth of their blacks by not being hurried. Five to ten minutes in the fixing bath, face down, and transparency examined against the light tells when fixing is complete.
- Washing is the one long operation and must be long, to remove every trace of hypo and keep the prints from yellowing or staining within months. Rather than change the water in dishes for two hours, the authors advise buying a good washer, which will handle about twenty 13×18 prints or a dozen 18×24 in under two hours of running water.
- Before hanging, the print is laid face up on a sheet of glass and wiped over with cotton wool soaked in water to remove handling marks and keep the margins clean. A drying rack is improvised from four battens strung with wire and cheap five-centime cravat clips, their teeth filed smooth so they do not cut the paper.
- Few prints are perfect, so scraping for black specks and spotting for white ones will usually be needed. On glossy C paper the work is difficult enough that the authors advise leaving small defects alone unless one is a past master of retouching.
- Trimming should never be neglected: the standard plate formats derive from the need to match glass to camera and have nothing to do with the finished image, and a print often gains by losing useless parts. If in doubt, cut square to format, lay the print on white, and mask the doubtful areas with a strip of the same white paper to judge the effect.
- Opens the Appendix with direct contact printing on gelatino paper, since a 9×12 negative yields a usable print at its own size. Nothing is needed but a printing frame and a feeble light — a small gas jet, a candle, even a wax match or an ember — the negative side being covered with a board or card between exposures; with a laboratory lamp uncapped at about 50 cm, exposures run sixty to a hundred and eighty seconds.
- Where direct enlargement onto paper is impossible, a triple operation is used: the negative is first copied as a glass positive by contact or in the three-body camera, that positive is then enlarged into a second negative of the size wanted, and the print is made by contact from it. There is no difficulty, only a good deal of work, and fineness gains nothing from the extra stages.
- A little-known method the authors have used with success: instead of developing in the dish, the developer is brushed on, attacking only the parts wanted or forcing them with a stronger reducer, while unwanted areas — a portrait background, for instance — are weakened after development with a brush loaded with prussiate. The reducing formula given is equal parts of 100 g hypo and 10 g potassium ferricyanide solutions, with about a quarter of the volume in glycerine added to stop it spreading.
- Toning is possible but the authors have no confidence in its permanence and think it rarely adds anything artistic. They give one formula from Marc Le Roux's Annuaire général — equal parts of 10 g potassium ferrocyanide and 10 g uranium nitrate solutions per litre — for warm red and warm brown tones, but conclude it is better to keep the paper's natural tint than to sacrifice its keeping qualities.