File:The American annual of photography (1922) (14801421413).jpg

Identifier: americanannualof36newy (find matches)
Title: The American annual of photography
Year: 1922 (1920s)
Authors:
Subjects: Photography
Publisher: New York : Tennant and Ward
Contributing Library: Harold B. Lee Library
Digitizing Sponsor: Brigham Young University

View Book Page: Book Viewer
About This Book: Catalog Entry
View All Images: All Images From Book
Click here to view book online to see this illustration in context in a browseable online version of this book.

Text Appearing Before Image:
trate of iron and am-monia (brown), 25 grains; ferric oxalate (Mercks or Mal-linckrodts), 15 grains; chloride of copper, 8 grains; oxalate ofpotassium, 33 grains; nirate of silver, 15 grains; oxalic acid,15 grains; gum arabic, 10 grains; 5% bichromate of po-tassium solution to suit (4 to 10 drops). There are a halfdozen variations of this formula (to suit special needs), butby modifying, it may be made to answer for any quality ofnegative, dense or otherwise. For example: All that is neces-sary when too vigorous is to dilute with distilled water. Onthe other hand, contrast may be had by adding more bichro-mate solution, by using a stronger developer, or by using a fewadditional grains of the iron. When from undiscoverable cause the formula refused toproduce prints up to the mark I have saved the day by addingto the sensitizer some 10 drops of platinum solution. Thesuccess of this experiment started a new line of thought, theresult being a new and less complicated formula, which, in 62
Text Appearing After Image:
Illustrating article Kallitype, by James Thomsotu. 63 the hands of the novice, is less likely to give trouble. As amatter of fact, I personally for years have used no other.The formula is as follows: Distilled water, i ounce; citrateof iron and ammonia (green scales), 20 grains; ferric oxalate,20 grains; oxalate of potassium, 18 grains; gum arable,10 grains; platinum solution 10 drops; bichromate solutionfrom 4 to 10 drops. This forms a clear solution thatordinarily requires no filtering. Put aside for twenty-fourhours before using, then shake thoroughly. When ferric oxalate is in prime order excellent blacks areobtainable, but in any event good browns are possible. Brownsof purple cast are resultant of a preponderance of ammoniairon citrate over the ferric oxalate. As regards the No. i formula care must be exercised incompounding. Place the ounce of water in a dark bottle andadd the chemicals in the order given. Turn bottle upside downonce or twice and put away for twenty-four hours

Note About Images