REDUCTION The negatives being thoroughly fixed may be lifted from the fixing bath, rinsed once and ex amined on the above device to see if there are any which require reducing locally or entirely. If a negative be found too dense throughout it should be dipped once more in water and placed in the following well known Farmer's reducer: Ferricyanide of potassium (red prussiate of potash). 15 grains Hyposulphite of soda 90 " Water 2 to 3 ounces Or without weighing: Ferricyanide about the volume of two peas Hypo about six times that volume, and Water 1/3 to 1/2 of a glass Weighing is unnecessary and the less water the quicker the solution works and the oftener the plate should be examined while in the bath. When it reaches the desired opacity dip in water and then pass to another clean water where it may rest until all are reduced which require it.
It is frequently desired to reduce some par ticular area of a negative without altering the rest of it. This is termed "local" reduction. Such an area may be that of white drapery which, in the time required to print the face correctly, would not be sufficiently detailed by the penetration of the light through that part. It might be the sky with clouds in an exterior or the small areas of white objects, as gloves or flowers, or the reflections from metal or other reflecting surfaces. Or it might be that the density of a road or path or the shadows of drapery folds require to be lowered, or perhaps it is some part of a background or drapery in a portrait.
Too great reduction of any local part makes that part "out of tone," unless the part be where deep shadows might naturally have been in the arrangement of a subject as for example the lower part of the clothing in a bust portrait, the detail and somewhat high tone of which it is frequently desired to eliminate in order to secure a so-called broad effect. The out of tone effect above mentioned is easily detected as it represents the part as darker than it could have been, in relation to the objects about it, under the light conditions which prevailed and which should be evident from the appearance of any picture. A little practice will suffice to teach anyone how far he may go in this work of local reduction.
In reducing locally it is annoying to find after the reducer has been mixed a minute or two, that its vigor is gone and a different "technique" is advised to avoid this trouble. Place in separate small graduates the two chemicals mentioned in the formula above (without weighing). Then add
enough water to the hypo to just nicely dissolve it. Then fill the other graduate up to the same level and dissolve. Then to use, squeeze out with the finger two or three of the small, quill, camel's hair brushes of each solution into another very small dish and use from that. As soon as its action slows, rinse the dish and the brush and combine another small quantity as needed. In this manner one can work with a full strength solution until the two solutions are used up.
For reducing small areas use very little water in mixing the above solutions in order to make it work very fast and see also that the excess of water is removed from the area to be treated before the reducer is applied. This may be done by passing a piece of slightly moistened absorbent cotton over it. A soft brush should be chosen appropriate to the size of the area to be treated and the excess of solution should be pressed from it in order that on touching it to that area the solution will not run to the adjacent areas and reduce in a spot or path (as this solution works almost instantaneously) where it is not desired. The speed with which the solution works when very little water is used makes it possible even to draw lines in the negative if desired but the necessity for care and good taste increases with the liberties which are taken in the work. One should have in the left hand a tuft of wet absorb ent cotton ready to apply to the part treated, as the delay of a single second could easily spoil a negative completely. A short appli cation of the reducer followed by that of the wet cotton allows the work to be done tenta tively, making it much easier to watch and con trol. As has been mentioned in the chapter on developing, the best fixing bath is a fresh one made of hypo and water only, as with thorough fixing and cleanliness no fear need be had of stains during or following reduction and intensi fication.
Should a number of negatives have been de veloped at one time it is best to leave the whole batch in the first wash water until those requiring to be reduced have all been treated. All may then be given four changes of water to prepare for intensification. If it should be necessary, even those which have been once reduced may be now intensified either locally or generally. Intensification may now proceed.