This section is from the "Studio light a magazine of information for the profession 1918" book, by Sara F. T. Price. Also see Amazon: Studio light a magazine of information for the profession 1918.
Is simply a sliding block containing an opening covered with ruby glass and another that is quite uncovered. Focus at once through the ruby glass aperture, with certainty and without risk of fog - then slide the uncovered aperture before the lens to make the exposure.
No. 1 - -For lens barrels 1 1/2 to 2 1/4 inches in diameter ....
No. 2 For lens barrels 2 1/4 to 8 inches in diameter ....
No. 3 - For lens barrels 3 to 3 7/8 inches in diameter ....
MILKY FIXING BATHS
In advance of its season we give the measures that should be taken to overcome it.
The milkiness is an indication that the bath contains sulphur and the result is brown or yellow spots and sometimes a brown tone over the entire print.
Prints must be hardened, and alum is the best hardener, but alum in combination with Hypo will release sulphur which makes the trouble. Acetic Acid of proper strength, in combination with pure sulphite of soda, forms a gas which prevents this release of sulphur and forms a perfectly balanced fixing bath.
Impure sulphite containing sulphate, sulphite exposed to the air and becoming sulphate, acetic acid used too strong or in too great a quantity, or the addition of the hardener to the hypo solution before the hypo is thoroughly dissolved will release sulphur and cause trouble first mentioned. If the hypo bath becomes hot, the gas formed in the solution by the acetic acid and sulphite of soda will partly escape and allow the sulphur to be released.
Prints which have been fixed in a bath containing sulphur may not begin to discolor until they are laid out to dry so the only safe plan is to be sure of the fixing bath. Have a stock solution of hardener made of pure fresh chemicals. Make a fresh fixing bath, use it while fresh, do not allow it to become warm and throw it away when your prints are fixed.
THE REGULAR THURSDAY NOON SUMMER BAND CONCERT GIVEN FOR EMPLOYEES ON THE KODAK PARK LAWN MORE LENSES NEEDED The work of the Signal Corps - the work of equipping cameras for our great fleet of aeroplanes - the actual work of the boys who must fly over no-man's-land to bring back to Pershing photographic information on which depends the safety of our troops in the trenches - success or failure depends upon a continuous supply of lenses for this work.
Thousands of men are in training for this important service and many are ready to go. Others are already "over there," and their urgent need is equipment.Thousands of lenses are needed at once by the Signal Corps and thousands of photographers must enlist their lenses promptly if this important department is to be properly equipped for its work in France.
The lenses must be had, and you have them - not every photographer, to be sure, for many have offered their lenses and these have been purchased. Some have even sent lenses asking the Signal Corps to set fair prices, but this cannot be done. This department can buy your lenses at the prices you ask if they are in good condition, but it is important that you at once send a list of those you have - all anas-tigmats of from 8 1/2 to 24 inch focal length.
Address, Office of Chief Signal Officer, Signal Equipment No.33, 119 D St., N. E., Washington, D. C. List all the anastigmat lenses you have, giving name, focal length, serial number and working aperture. The lenses most urgently needed will be purchased at once - the others will be card indexed and ordered in as needed.
Don't hold off waiting for the other photographer to do his bit - your lens is needed at once and your patriotism may make him ashamed of his delay in answering the call.
Cameras are ready, aeroplanes are ready, men are ready. The manufacture of all equipment is being speeded up and thousands of lenses are needed where hundreds are being offered.
Where there has been congestion there is now order and every offer of lenses will be acted upon promptly. And for every lens you offer there is one on the market, almost if not equally suitable for your use.You are not asked to give these lenses away - you are asked to sell them at a price that will be satisfactory to you and that will enable you to buy lenses to take their place.
Do your bit and do it at once.
The boy "over there" may have a portrait of Mother - but he'd like one of "Dad" too - send one in the next letter.Make an appointment today.
THE PYRO STUDIO
Line cut No. 250. Price, 50 cents.
"THEY'VE THROWN ME DOWN! I CAN'T GO TO FRANCE!"
The Lejaren a Hiller Studios Courtesy of Judge
STUDIO LIGHT INCORPORATING THE ARISTO EAGLE ESTABLISHED 19O1 THE ARTURA BULLETIN ESTABLISHED 1906 Vol. 10 APRIL 1918 No. 2