A problem in studio construction which is especially difficult to solve satisfactorily is how to build a skylight to secure the best and most uniform illumination when an adjacent building obstructs the light at the point where the skylight should be located. This is especially difficult when the space between the buildings must be narrow and the obstructing wall is very high.

In extreme cases, perhaps the only satisfactory way to solve this problem is to abandon the idea of having a northern exposure for the skylight and erect an east, south or even a west light, which we mention in order of preference.Next to a north light an east light would be recommended.

FROM A BROMIDE PRINT

By Pearl Grace Loehr New York, N. Y.

When this is not expedient, choose the south, and only as a last resort the west light. The reason for these various types we may elaborate more fully in some future article for Studio Light. Just now we are dealing with the question of angles, reflections and refractions when building a north light and having an opposite building to contend with.

Some photographers when attempting to grapple with the difficulty resort to a dependence upon reflected light. They argue that by painting or whitewashing the opposite wall it will afford sufficient illumination.

The fallacy of this conclusion, even if the light was reflected into the studio, will be seen at a glance if we remember the axiom that light diminishes in ratio to the square of the distance from its source.

Reflected light, therefore, at a distance of four feet from the white wall would be one-sixteenth as strong as the illumination on the wall itself and at ten feet only one one-hundredth as strong. This disposes of the idea of reflected light, for anyone will appreciate the difficulty of trying to work under such conditions, especially in dull weather.

Another thing which is not properly considered is the angle of reflection. The law of reflection is that the angle of reflection is equal and corresponds to the angle of incidence. For example,light striking a white screen, reflector or mirror at a certain angle is reflected from such surface at the same angle. Light falling on a surface at an oblique angle is reflected at an oblique angle; if at an acute angle, the reflection is acute and a right angle reflection only occurs when light falls at an angle of 45 degrees to the surface of the reflector.

The accompanying drawing will illustrate this. "A" represents the window or skylight and "B" the reflector. The straight lines extending upward at an angle of 60 degrees represent the oblique angle of incidence, which is the general direction of light from the sky into the light well between the buildings. The straight downward lines represent the corresponding oblique angle of greatest reflection. The dotted lines show where the photographer wants the most light but where he really gets the least reflection.

FROM A BROMIDE PRINT

By Pearl Grace Loehr New York, N. Y.

A very good way to secure illumination is by refracted light obtained by means of using prism glass. However, the use of such glass involves a somewhat intricate problem in placing a skylight at the proper angle to correspond to the peculiar angle of the prisms in the glass. We will not go into this matter, as space does not permit, and each case presents an individual problem.

The most practicable and feasible method of overcoming obstructions is to elevate the studio - in other words to rise above your troubles. This is easy where one can build a two-story studio. If placing the operating room on the second floor does not lift the skylight quite high enough to get unobstructed light, the operating room floor may be raised a couple of feet above the rest of the second floor.

In the case of a ground floor studio with an adjoining two-story building on the north side, the main portion of the studio, including reception room, work room, etc., would be on the ground floor. Back of this, and several feet higher, the operating room should be built. And by placing skylight as far as possible from the adjoining building and having the floor elevated the obstruction is overcome.

To illustrate a specific case we will suppose a photographer in a small town has a corner lot with a 30 foot frontage and a 68 foot depth. Next to him on the north is a building 22 feet high.

The photographer in this case would overcome his trouble and secure good illumination and really have a most attractive studio by building somewhat in accordance with the plan which we print herewith as an illustration.

By having the operating room up a short flight of steps a certain seclusion is secured and an air of elegance is given to the entire studio. At slight additional cost, a basement storeroom could be made under the operating room. It will be seen that the space between the buildings is great enough for the light to pass over the building and illuminate the skylight at its lowest point.

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