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MAXIM MUIRS BLUE-BLACK (PAPER)

Il Maxim Muirs Blue Black e uno sviluppo attivissimo per carte restituisce un tono freddo brillantissimo ed e uno sviluppo PQ cioe phenidoneidroquinone e per questo riduce i problemi per chi e allergico agli acidi Lalta quantit224 di Idroquinone permette di avere un ottimo contrasto anche a diluizioni spinte e lattivit224 della soluzione di lavoro rimane invariata dopo numerose stampe Prima che continuate a leggere devo dire che la preparazione di questo sviluppo e estremamente semplice ma e anche la piu lunga come tempi e una delle piu costose tra tutte le preparazioni provate per le stampe [diciamo che 1 litro di sol stock per 15 litri di sol finale cercando di risparmiare dovrebbe costare intorno ai 1015 euro a preparazione] La singole quantit224 dei chimici sono notevoli e saturano facilmente per questo serve molto tempo e pazienza per scioglierle ma il risultato appaghera adeguatamente la fatica profusa I chimici utilizzati sono quasi tutti di facile reperimento su internet [soliti fotomatica o tuttofoto] ma alcuni costano molto Si risparmia notevolmente acquistando le preparazioni anidre presso i laboratori di chimica appositi ma mi rendo perfettamente conto che in molte citt224 sono di difficile reperibilit224 Il Fenidone e difficile da trovare anche non trattato quindi per questo componente posso dirvi subito che molto probabilmente dovrete acquistarlo su internet Per il benzotriazolo la ricerca sar224 ancora piu lunga e onerosa 1Kg di benzo se non sbaglio viene circa 200 euro ma niente paura: primo lo potrete usare diluito in soluzione al 1 (10g in 1 litro di acqua) per ottenere toni nettamente migliori con il bromophen (circa 5ml per litro) e secondo 100g di benzo sono piu che sifficienti per circa 50 preparazioni stock di Muirs [pari ad oltre 500 litri di sol di lavoro] spendendo solo 20 euro Idem per il Pehidone ne bastano 100g per 50 preparazioni 1Kg di sodio solfito invece costa zero e lidrochinone se lo trovate non trattato lo pagherete meno di un decimo rispetto alle preparazioni Ornano in vendita su Internet [Prosegue]

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FX-11 FILM DEVELOPER

Geoffrey Crawley is present editor of The British Journal of Photography In 1960 and 1961 he proposed a group of Black and White Developers Designated FX Series This developer was compounded to give fullest possible speed increase with the minimum granularity increase Modified to USA chemical availability FX-11 offers a ASA speed increase of 80 to 100) FX 11 gives higher film speed than either Promicrol or Microphen It probably gives the highest speed available at present in a solvent developer with balanced toe contrast to ensure good gradation with thin enlarging contrast negatives It has biult in sheen to mask granularity by slight diffussion definiition is not outstanding owing to the high rate of physical development but sharpness is fairly good Its sensitometry and sheen is sush that with correct exposure and development no marked rise in granularity should be noted over commercial formulae despite its high speed exploitation In FX 11 a preference for thin negatives with a density scale of about 08 0 or 09 over fog and base and a normal contrast was assumed the sensitometry of the develeloper is such that best quality is reached at that point and it is not therefore very suitable for formats over 6x9 cm where a higher density scale is ofen required: By the time this higher density is reached negative quality - granularity sharpness and definition - will have fallen off To obtain best quality at a higher contrast with no effect on the increased film speed increase glycin by 05 gramliter development times will increase slightly This speed increase may still be obtained on conventional contemporary films and to an extent with tabular films However with tabular films which seem to to respond less well to high-sulfite formulae we recommend diluting FX 11 1:3 or more A variation for T-Max or Delta tabular grain films with just 30 g of Sodium Sulfite complements the Glycin characteristic of working best in low concentrations of sulfite Glycin has a tendency to become excessively solvent when it is placed in a high-sulfite solution [Prosegue]

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FX-2 HIGH ACUTANCE FILM DEVELOPER

FX-2 produces negatives with a high degree of sharpness and normal grain with the capability of interesting internal effects Due to the greater definition obtainable with FX-2 grain is less apparent than D-76 Compared with FX-1 FX-2 produces negatives with finer grain but less acutance but both have distinctly different pleasing effects FX-2 used as a stand developer for one hour produces the most interesting internal contrast effects of the FX developers FX 2K a variation provides more flexibility with enhanced midtones FOR YOUR CHEMICAL SAFETY [Prosegue]

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IRON BLUE TONER

Iron Blue toner is an inexpensive but effective toner that is equivalent to Ansco Toner 241 The toner will work on most papers but each type of paper will yield a slightly different tone Blue toning is a favorite of those photographers working with winter or water scenes Just a hint of blue enhances the impression of winter snow and softens an otherwise stark photograph A number of different formulations for iron blue toners been published All of the formulations are based upon the formation of Prussian blue The chemicals in this formula give a brilliant blue tone To allow you to vary the blue color to a softer blue-gray tone this formula also contains borax for the preparation of an afterbath A blue-green tone may be obtained by toning the well washed blue toned print in a sulfide bath The sulfide bath is a 1 solution of sodium sulfide with hydrochloric acid at a ratio of 1 part acid to 50 parts bath The print is immersed until the color changes to a blue-green Prints intended for this treatment should be slightly dark Discard bath immediately after use A split tone effect with deep blue shadows and brown highlights may be obtained by first toning in sulfur-based toner such as Hypo-Alum Sepia Brown or Polysulfide Paper Toner (Kodak T-8) followed by an iron toner such as Iron Blue Toner NOTE: Ferric Ammonium Citrate is somewhat light sensitive and should be stored in the dark or a dark brown container [Prosegue]

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