Only the briefest suggestions can be given as to the general arrangement of interior views on the focussing-screen, as so much will depend upon the subject; but there are a few rules which apply to most cases. The camera should not be placed in the middle of a nave, aisle, or passage, but nearer to one side, so as to avoid a too symmetrical arrangement of lines. If arches form a prominent feature, some support should always be shown (a column, or portion of one) at the side of the photograph. The effect of an arch springing out of the picture, either at the side or top, is almost invariably bad. The greater the amount of unsupported arch shown, the more unpleasing will be the result. If the apex of an arch cannot be included, it is usually more satisfactory to cut off the arch just above the capitals. Bases of piers and columns should always be included. Sacrifice the top of the picture rather than foreground when it is found impossible to take all that is desired on one plate, except in record work, where pictorial effect is not a consideration. A rather low view-point, such as the level of the eyes of a person sitting down, or kneeling, will often give a pleasanter result than a high one, as the latter tends to make the foreground appear "steep." When difficulty is experienced in including the top of the subject and sufficient foreground, it can frequently be overcome by lowering the camera, and further raising the front.
The photographer of interiors is often hampered by chairs and benches, and, when possible, these should be moved out of the way. When they are too numerous for this to be done, or are fixtures, advantage should be taken of any opening, or passage, to break up the foreground, and help the eye into the picture.
Choir Of St. Pierre, Chartres.
E. A. and G. R. Reeve.
There are various dodges for preventing the ends of tripod legs from slipping on a smooth floor. Pieces of rubber or cork may be fitted to the points, or a string tied round the legs. Some use a device of three thin slats of wood fastened together at one end, and radiated and having indentations in which to place the points of the tripod legs. A mat may sometimes be handy, and will serve the same purpose. But with most floors, in cathedrals and churches, there is usually no need of these devices, if the tripod legs are not spread very wide.
The usual method of focussing, that is, focus the principal object, and stop down till the rest of the picture is sufficiently sharp, applies to interior as to exterior work. The amount of stopping down necessary to secure the requisite depth of field will of course vary with the length of focus of the lens. With a lens of five inches equivalent focus, provided the covering power and definition are good, there is often no necessity to use a smaller stop than f/8 or f/11, and with many subjects even f/6 gives satisfactory results. The photograph of the choir of St. Pierre, Chartres, reproduced on the opposite page, was taken on a quarter-plate (Lumiere anti-halo) with a five-inch lens at f/8. Some photographers, in taking general views, focus an object roughly a quarter of the distance from the foreground to the furthest point, and then stop down till the latter is sharp. In very dark interiors a focussing magnifier, used as recommended for telephotography, is of great assistance. When, owing to insufficient light, difficulty is experienced in seeing how much foreground is included on the screen, or how much at either side of the picture, a piece of white paper or a handkerchief placed on the floor will often prove helpful, or, if the photographer is fortunate enough to be working with a friend, a lighted match, held in the required position, will enable him to find the nearest point of foreground, and also to judge the focus. The same methods are useful in focussing any dark object in a bad light.
Flashlight is sometimes employed to lighten dark shadows in interiors, but it will seldom be found necessary. When used in this manner as an auxiliary to daylight, care must be taken in selecting the position of the flash so as not to produce a false lighting, which could not possibly have come from a window or doorway.
There is considerable diversity of opinion among architectural workers as to the utility, or otherwise, of exposure meters for interior work. Some experts hold that meters are practically valueless, while others strongly advocate the use of them on every possible occasion. Personally we have found that the paper supplied in meters is not sufficiently sensitive to interior lighting, and we have known the correct time of exposure elapse without the paper showing any perceptible sign of change, let alone darkening to the "quarter tint." When the light, is coloured by stained glass the relative sensitiveness of meter and plate may vary widely.
A simple rule, which many workers find helpful, is to stop down until detail is only just visible on the focussing screen in the darkest parts of the subject, and then expose for ten minutes, using an extra rapid plate. Such a method no doubt forms a useful guide in determining exposure, but there are varying factors which must be taken into account, such as the actinic value of the light in different interiors, and also the visual ability to discern details on a dark focussing screen, a faculty which all photographers do not possess in equal measure.