The Spoontable
If you're a chemist, give up now. Go and read "All About Cookery", by Mrs Isabella Beeton, you'll get the idea of what follows. If you're not a chemist, preferably with no knowledge of chemistry beyond that needed to put vinegar on your chips, read on.
There are photographers out there who make up their recipies using common or garden teaspoons to measure out the ingredients. Combined with consistent working methods they appear quite accurate enough for B&W work. Several books give equivalent weights for spoonfuls (spoonsful?) of common photographic chemicals. There's one in "The Darkroom Cookbook" by Anchell, for example. I have seen recipies published on the web with the ingredients given in spoonfuls, and one chap has a conversion table published on his website. None of these sources say anything about the size of the teaspoon nor do they say whether it is to be filled heaped, rounded or level. Forget the British Standard Teaspoon and fear not, help is at hand...
If, like us, you get a Betterware catalogue pushed through your letterbox every so often, look for item 48430 and voilá - Adjustable Measuring Spoons. There are two in the pack. A teaspoon size with a capacity of 5ml and a tablespoon size of 15mL.
The teaspoon size is marked in 1/8, 1/4, 1/2 and 3/4 (1.25 mL increments) whilst the table variety is marked in 1/2 teaspoons (2.5 mL increments). Now we come to the Table of Spoons, which gives the weight of a LEVEL tea or tablespoonful of some common B&W chemicals using the Adjustable
Measuring Spoon, so now you can make up your own solutions without needing a balance.
Fixed size measuring spoons are available from Lakeland Limited (015394 88100 or www.lakelandlimited.com) as item 5091. There are six in the set from 1/8 teaspoon (0.6mL) to one tablespoon (15mL)The Table of Spoons
This list gives the weight (g) of one level teaspoon or tablespoon of some common chemicals used in B&W processing and miscellaneous formulations. They use the Betterware Adjustable Measuring Spoons.
Teaspoon Weights
Kodalk 4.0g Borax ---------------------------------- 4.3g
Potassium metabisulphite ------------------------ 4.0g
Sodium sulphate (10H20) ------------------------- 4.0g
Hydroquinone --------------------------------------- 3.0g
Sodium sulphite (anh) ------------------------------ 7.0g
Potassium bromide ---------------------------------- 6.8g
Metol --------------------------------------------------- 2.3g
Potassium dichromate ------------------------------ 7.8g
Benzotriazole ----------------------------------------- 1.0g
Dimezone 'S' (Phenidone) -------------------------- 2.0g
Potassium ferricyanide ----------------------------- 4.9g
Thiourea (thiocarbamide) -------------------------- 3.1g
Pyrogallol ---------------------------------------------- 3.0gTablespoon Weights
Sodium thiosulphate (5H20) -------------------- 14.4g
Sodium metabisulphite --------------------------- 14.1g
Citric acid 10.9g Boric acid ---------------------- 11.5g
Sodium carbonate (anh) -------------------------- 8.0g
Potassium alum. ------------------------------------ 14.2g
Sodium hydroxide --------------------------------- 14.4g
Sodium sulphide (hydrate) ---------------------- 11.0gSo there you have it, weightless weighing and mixing.
John Pearle, Area 13. September, 2000.