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The Barnet Book of Photography A Collection of Practical Articles

If ferrous oxalate is not at hand


Ammonium sulphocyanide 20 grains Water 10 ounces

After immersion, rinse the print for five minutes and dry.

_Intensification._--It sometimes happens (especially when too little light has been used to properly judge development) that one acquires a collection of prints that, owing to under or over-development, are useless; let us see how they may be rendered serviceable.

An under-developed print, though weakly looking and "washed out," simply needs intensification to give it the requisite pluck. The foregoing uranium bath acts as an intensifier while conferring a ruddy tone on the deposit. A black deposit can be obtained by intensifying the well-washed print with mercury. The print must first be immersed in a saturated solution of mercuric chloride until the image disappears; it must then be again thoroughly washed to remove all traces of free mercury and may then be redeveloped by flowing over it an old ferrous-oxalate developer. If ferrous oxalate is not at hand, an old metol developer may be substituted, but the former is the more reliable.

When the image is sufficiently intense, the print must once more be thoroughly washed. All the toning and intensifying operations may be conducted by daylight.

_Reduction of Density._--Over dense prints can be made fit for many purposes

by means of a "reducer" capable of dissolving part of the deposit. The best for the purpose and the one least liable to cause stains is know as the Belitzski's; it is prepared thus:--

Water 60 ounces Potassium ferric oxalate 3 " Sodium sulphite 3 "

Dissolve and add to the red solution so obtained.

Oxalic acid 1 ounce

Shake until the solution turns green and then immediately pour off the solution from any crystals remaining undissolved. To this solution add

Hyposulphite of soda 15 ounces

and shake until dissolved, when it is ready for use.

The print to be reduced need not be free from hypo, but should be rinsed for a few minutes after fixing (or soaked until limp, if previously dried) and may then be placed in a tray and flooded with the reducer. The tray must be well rocked and the print, when sufficiently reduced, must be removed without delay and rapidly washed in running water.

_Some Cheap and Useful Trays._--If large-sized prints are made, the cost of suitable trays becomes a very serious item. The expense of these may be reduced to a mere nothing, without loss of effectiveness, by the substitution of home-made ones. All that is required to make a tray of any size is a thin wooden confectionery box (or the bottom part of a larger case) lined with the shiny white marbled oilcloth known as "American moleskin." This is fitted inside the box (the corners being turned under) and secured by a row of tacks around the top edge. No further lining or preparation is required and the tray will stand all sorts of ill-treatment. As for durability: I had three such trays made out of old herring-boxes picked up at Calgary and lined with moleskin that had already seen service as cover to a wash-handstand and chest of drawers in a Canadian boardinghouse. For upwards of a year those trays were used daily and travelled many hundreds of miles by mule and dog train, and were not worn out when I returned home. My porcelain trays were smashed by a fall from a refractory mule, but the rough and ready makeshifts were a priceless boon.


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