>While asking questions … could anyone direct me toward info on how to
>make a 'tintype'?
I just bought a Christmas present for myself: "The Scientific American
Cyclopedia of Receipts, Notes and Queries," 28th edition, 1909.
It has an extensive section on photography, which includes the
following:
Tin Types, Formulas for Making.--The plate is coated with a collodion
made as follows, but it can be bought at photo. dealers ready made:
1. Collodion.--Alcohol and ether, equal parts; gun cotton sufficient
to make moderately thick film, say 5 or 6 grn. to the oz.; put the
cotton in the ether first, when it is well saturated pour in the
alcohol, to which add:
Iodide of ammonium....4 grn. to the oz.
Iodide of cadmium.....2 grn. to the oz.
Bromide of cadmium....1 grn. to the oz.
Bromide of copper.....1 grn. to the oz.
There are 8 grn. of salt to the oz. When the collodion has set, the
plate is immersed in a silver bath, made by dissolving 50 grn. of
nitrate of silver in 1 oz. of distilled water, and kept there from two
to five minutes. It is then put into a plate holder, exposed for
twenty-nine seconds in the camera, and developed with the following:
2. Developer.--
Water.......................64 oz.
Protosulphate of iron........4 oz.
Acetic acid..................4 oz.
Alcoholic solution of
tannin, 10 grn. to the oz....4 oz.
The acid and tannin solutions should be added after iron has been
dissolved. The developer has to be flowed over the plate with one
sweep. The picture is fixed by putting the plate into--
Cyanide of potassium......2 oz.
Water....................64 oz.
Then washed and dried.
The manufacture of gun cotton is given as follows:
Gun Cotton.--It may be prepared in small quantities as follows: Mix 4
1/2 oz. of pure dry nitrate of potash with 30 fl. drm. sulphuric acid,
specific gravity 1.845, and, after cooling thoroughly, stir into this
mixture carefully 120 grn. best carded cotton. As soon as saturation is
complete, in about one minute--if proper care has been used--throw the
cotton into a tubful of clean rain water, and change the water
repeatedly until litmus ceases to show the presence of acid, then
squeeze it in a cloth, and after being well pulled out, dry it
cautiously at a temperature not exceeding 140 deg. F. It is now
explosive, and too much caution cannot be observed in handling it.
Elsewhere in the Cyclopedia, protosulphate of iron is defined as ferrous
sulfate (FESO4).
There are 8 fluid drachms to the fluid ounce in apothecaries' liquid
measure. There are 7,000 grains to the avoirdupois pound.
Good luck, and be sure to count your fingers after you try it.
-- Dennis M. Southwood dms1@home.com