The camera used should be of a substantial character, as naturally, when working with filters, the exposure is sometimes long and all unsteadiness must be avoided. The square bellows, long extension type, is best, as with such a camera there is less risk of internal reflections. The camera should have provision for plenty of rise and fall of front, and also possess a swing back. Its rack and pinion focussing should be worked from the back. The stand should also be substantial ; a good studio stand is best.The lens should be of the highest quality that can be afforded. An anastigmat is best, but it is not necessary to spend money in procuring a lens of a large aperture, as furniture is always photographed at close range, and as the object is seldom in one plane, and the photograph must be sharp throughout, a stop of large aperture cannot be used, owing to the want of depth of focus. It is very seldom that an aperture larger than F. 16 can be used, so that it is unnecessary to pay a big price for a lens because, for example, it works at F. 4.

The focus of the lens should be as long as possible. A lens of 18" focus is suitable, and in any case it should not be less than 12".If the focus of the lens is shorter than this, the perspective will be exaggerated and objects may look distorted.

Focussing

As it is necessary, as a rule, to get the whole of the object as sharp as possible, a compromise must be made in focussing. If the front is focused sharply the back will not be sharp enough; if the back or even middle depth is focussed correctly, the front will not be sharp. The best compromise is made when a point is chosen about one-third of the distance from the front to the back of the object, and that point focussed.Focussing should be done with a medium stop if there is sufficient light, say F. 16, rather than with a larger aperture, but not smaller than F. 16. An aid to focussing is to put a piece of printed matter at the position where the most accurate focus is required and focus on this.

Extraneous Light Must Not Enter Lens

It is necessary to prevent any light except that coming from the object itself, entering the lens, and therefore if there is any strong top light, a hood or lens shade should be used, which should be so arranged as to cut off all light except that reaching the plate from the object to be photographed. If this is not attended to, a good deal of diffused light very often enters the lens and veils the negative.

The Filters Necessary

The most useful all-round filter is, without doubt, the Wrat-ten "G" (strong yellow). This gives slightly more correction than the eye sees and will show the grain of most woods quite well. Where, however, it is required to exaggerate the detail in mahogany, rose-wood and other dark woods, it is desirable to use a deeper filter, for example, the red "A, "and in some cases, such as very dark old woods or woods which have been stained to have the appearance of great age, even a deeper filter still can be used with ad vantage, namely the Wrat-ten "F" (deep red). For furniture with tapestry, in which it is desired to show the details in the same relative brightness as the eye sees them, it is better to use the K3 (yellow) filter.

When furniture is decorated with painted designs, medallions or other colored decorations, also in cases where furniture is entirely upholstered in light-colored upholstery, or in the photography of carpets and rugs, which often comes in the work of the furniture photographer, also for some lacquered furniture, such as screens in which perhaps brilliant colors are included, it is preferable to use the K3.

The Filters Necessary StudioLightMagazine1915 124

FROM AN ARTURA IRIS PRINT

Copyrighted by Emma B. Freeman Eureka, Cal.

The Filters Necessary StudioLightMagazine1915 126

FROM AN ARTURA IRIS PRINT

Copyrighted by Emma B. Freeman Eureka, Cal.

It should be added that though it is necessary always to use a color-sensitive plate, that is, a Wratten panchromatic, it is not always necessary to use a filter as well. Sometimes the effect is secured without any filter at all in very light woods, and the Kl (very light yellow) affords sufficient correction for bird's-eye maple, chestnut, holly and satin-wood. If these woods are over-corrected it spoils to some extent the representation of their texture. On the other hand, if they are mixed with other darker woods and it is desired to show the general effect, then the K3 filter should be used.

Kinds Of Filters

Wratten filters are supplied in the form of gelatine film, but this is not recommended except for preliminary experiments, as the film rapidly deteriorates with handling and exposure. They are better cemented in good optical glass, our "B quality," and best cemented in "A quality" glass which is worked plane parallel, and these form the finest filters possible to procure.

Generally speaking, the B quality is sufficiently satisfactory, but if work of highly critical definition is required, it is necessary to use the A quality. These latter filters are made with the accuracy and precision of the best anastigmat lenses.

(To be continued.)