Humidity doesn't usually bother a photographer until it affects his bodily comfort along with hot weather, but humidity is a bad thing for sensitized materials, especially paper.

One of the first precautions a photographer should take in damp weather is for the proper storage of paper. A work room containing sinks is more likely to be damp than any other part of the studio. If possible, have a dry cupboard for storing paper outside the work room.

It is a common custom to open a box of paper, remove the wrapping and place the paper back in the box, leaving it unwrapped until it is used up. It is a better plan to take out the paper that is needed, wrap the balance and place it where it will keep dry. There is no need to expose an entire gross of paper to the damp air of the printing room when only a few dozen prints are to be made.

As fast as exposures are made the undeveloped prints are usually placed in a second box kept for this purpose. If this box is kept in the work room, it is very likely to become damp and prints will also become damp if left in this box for any length of time before they are developed.

The latent image will fade if exposed prints are not developed for some time, but it will fade more rapidly if the paper becomes damp than if it remains dry. Even a few hours will sometimes make a marked difference, and experiments have shown that under extreme conditions of moisture half an hour is sufficient time to fade an image if it comes in contact with a damp surface.

A clean blotter that had received no moisture other than that absorbed from the air on a damp day was laid on a table and exposed prints were placed in a pile on this blotter. In half an hour the bottom print was developed. A decidedly mottled result showed that where the paper had come in contact with the blotter the image had faded, making the light spots, while the entire print had the effect of slight under-exposure.

There is no known remedy and the best means of prevention is to develop prints as soon as possible after exposures are made.

There is no excuse for allowing prints to lie over night before they are developed and, to maintain uniform quality, it is not advisable to even allow them to lie for a few hours. In any event, the box in which prints are placed previous to development should always be dry.

When the latent image fades the print has the effect of having been under-exposed. If your printer does not know this and has allowed exposures to stand for some time before development he may imagine he has been under-exposing, that the intensity of his light has decreased or that he has struck an emulsion of paper that is slow. The trouble can readily be detected if a print is made and immediately developed. If the print develops properly the trouble is not with the paper or the printing light but is due to this fading of the undeveloped image.

There is one other cause for fading of the latent image. If an undeveloped print is allowed to lie in a red light for several hours, even though the light is perfectly safe for handling paper without fogging, the latent image will fade considerbly. The fading is caused by alchemical action which the red rays of light accelerate, but as undeveloped prints are seldom left face up in a red light, this trouble will seldom be encountered.

Bromide Enlargement, From Seed Graflex Negative.

Bromide Enlargement, From Seed Graflex Negative.

From "Joan the Woman" Directed by Cecil B. De Mille.

Very little is actually known about the latent image, and while theories may be advanced regarding the cause of such troubles as those mentioned above, they are only theories and of no practical value to the man who depends upon results for his bread and butter. The all important thing is to know how to avoid such troubles.

There is one other trouble occasionally encountered that can be blamed to damp paper but which is due to dampness in the emulsion previous to exposure and development. The image fails to develop in spots and as the rest of the print develops the spot becomes a white irregular marking that appears not to have been coated with emulsion. This trouble seldom occurs when a fresh, normal strength developer is used. The paper has absorbed moisture unevenly and, in spots, repels a developer which is weak in alkali and does not have sufficient penetrating qualities.

A stronger developer contains more alkali and will, as a rule, overcome the trouble. Impure or weak carbonate of soda may have been used in making the developer, in which case more carbonate should be used. In every case where these markings occur, spreading the paper out in a warm dry place will dry out the moisture and overcome the trouble, which shows that it is caused by moisture and not defective coating.

If you do not have a dry place to store paper it is advisable to have a drying box made for this purpose. Any air-tight tin box large enough to hold your stock of paper can be made to answer the purpose. The important thing is to have it air-tight. The simplest way to keep the air in the box dry is to have a compartment in which to store calcium chloride. This will absorb any moisture admitted when the box is opened. The calcium chloride should be placed in a tin box with a perforated cover and as soon as it becomes damp it should be dried in an oven. It may be used over and over again and will keep the air in the box thoroughly dry if it is dried as often asit becomes moist. Never allow paper to come in contact with the calcium chloride as it will cause spots. Do not leave the box open any longer than necessary and it will not be necessary to dry out the calcium chloride so often. Calcium chloride may be purchased in anhydrous form and so used or it may be made into a saturated solution and added to the commercial form of asbestos until a thick paste is formed. The asbestos merely makes the calcium chloride more convenient to handle in drying.

Bromide Enlargement, From Seed Graflex Negative.

Bromide Enlargement, From Seed Graflex Negative.

From "Joan the Woman " Directed by Cecil B. De Mille.

Artura Iris Print, From Eastman Portrait Film Negative.

Artura Iris Print, From Eastman Portrait Film Negative.

New F. & S. Studio Shutter

The new F. & S. Studio Shutter has been designed to meet the demand for an exposing mechanism of simple and durable construction that will operate with such extremely silent and positive action that the operator can give undivided attention to the subject and secure exposures without the subject's knowledge that exposures are being made.

The shutter fits the lens board aperture of the camera, and the exposing curtains, located back of the lens, are actuated by means of a large rubber bulb and tubing.

A slight pressure on the bulb causes the shutter to rapidly and silently open and removal of the pressure results in equally rapid and silent closing.

A greater freedom of movement is afforded the operator by the use of extra tubing, supplied in six-foot lengths, which can be quickly coupled together, permitting the operator to work at any desirable distance from the camera.

New F S Studio Shutter StudioLightMagazine1917 182

Objectionable expansion or kinking of the tubing is prevented by a closely braided outer casing, and the rubber bulb provided is sufficiently large to positively control the shutter curtains when a considerable length of tubing is used.

The shutter is very substantially made with front and lens board finished in polished mahogany, and by means of extra shutter lens boards any number of different lenses can be interchangeably used without removing shutter from the camera.

The F. & S. Studio Shutter is made for Century and F. & S. Cameras only.

F. & S. Studio Shutter No. 1, for No. 2 Home Portrait Camera and 8 x 10 Commercial Camera, including lens board

Outside Measurements

Opening

Price

7x7 inches

4 inches

$11.00

F. & S. Studio Shutter No. 2, for 8 x 10 Studio Cameras

Outside Measurements

Opening

Price

9 x 9 inches

5 inches

$13.00

F. & S. Studio Shutter No. 3, for 11 x 14 Studio Cameras

Outside Measurements

Opening

Price

10 x 10 inches

5 inches

$13.00

Prices f. o. b. Rochester, N. Y.

It is false economy to work your fixing bath beyond its power.

Artura Iris Print, From Eastman Portrait Film Negative.

Artura Iris Print, From Eastman Portrait Film Negative.