This section is from the book "Complete Self-Instructing Library Of Practical Photography", by J. B. Schriever. Also available from Amazon: Complete Self-Instructing Library Of Practical Photography.
Other Materials. Bottles for your collodion, same or similar to those used for wet plate process; bottles for developer, and silver bath: glass baths for holding the silver, and one for fixing bath; two dippers - one for silver and one for fixing bath. You should also have one or two glass funnels for filtering.
1004. Ferrotype plates may be purchased by the box or by the dozen. For the beginner a few dozen plates will be sufficient. Purchase the 10 x 14 size and with a shears cut them into four parts; this will give you four 5 x 7 plates. On each 5 x 7 plate you can make four of the ordinary size tintypes. At summer resorts these pictures are often sold as high as four for one dollar. Ordinarily, however, 50 cents is the price for four pictures.
Making The Collodion. Collodion can be purchased ready for use. The Anthony Positive Collodion, which can be purchased from any photographic dealer, will be found exceptionally good and economical. However, for the benefit of those who desire to make their own collodion we give the following formula :
20 fl. ozs.
Gun - Cotton
Bromide of Cadmium
.............. 100 grs.
Iodide of Cadmium
Iodide of Ammonium . .
Place your gun-cotton in a large-mouthed bottle or graduate; add to this the alcohol and then the ether. When the gun-cotton is entirely dissolved, filter.
Bromo - Iodize. The ether, alcohol and gun-cotton mixture comprises the plain collodion. It must now be bromo - iodized. This is done by simply pouring into a clean graduate a few ounces of the plain collodion and then adding the bromide of cadmium, the iodide of cadmium and the iodide of ammonium. Stir with a glass rod until all ingredients are dissolved, and then add them to the balance of plain collodion.
Plain Collodion. The following formula is also an exceptionally good one:
Ether, specific gravity 725
..............10 fl. ozs.
Alcohol, specific gravity 805 ..
...............5 fl. ozs.
Gun - Cotton
Pour your alcohol on the gun-cotton, then your ether, after which filter. This is your Plain Collodion.