Early Work In Photography
A Text-book For Beginners

The Outfit. 43 known as “double plate-holders,” or " double dark-slides.” We have but little to say regarding the lens in this chapter, as the principles of its action are of sufficient im- portance to receive consideration in a special chapter ; we shall here simply content ourselves by giving a word or two of advice as to the lens best adapted to amateur re- quirements. For all ordinary purposes of photograpliy, including out- door groups and portraits, general views, and copying work, what is known as a single landscape lens is quite good. If we wish to photograph buildings the full size of the plate, we cannot use such a lens, otherwise the chief lines will not be absolutely rectilinear; the cause will be found in the next chapter. For such subjects we must make use of a "rapid rectilinear” lens which, being a doublet, will cost considerably more than a single lens. For interiors of rooms, where it is neces- sary to include a very wide angle of view, we must use a lens of extremely short focus, commonly known as a “wide- angle” lens. A wide-angle lens should never be used where it is possible to do the work without it. If only one lens can be afforded, we advise the student to buy a “rapid rectilinear " (just large enough to cover the largest plate he intends to use) which is the best general lens for all-round work: that he can have. By simply removing the front combination of such a lens, it is at once transformed into a single lens of about double the original focus; that is to say, will require double the distance that was required with the double combination to intervene between lens and plate. The extension of focus (as will be explained) narrows the field of view, and consequently projects an image on a much larger scale—a valuable power in the hands of a photo- grapher. With our own whole-plate outfit we possess only two lenses, yet we have practically a battery at our disposal. One of them is a rapid rectilinear of ii inches focus, the back: combination is 17 inches focus and the front combination (which may be used in place of the back one when necessary) is 21 inches focus. The other lens is a wide-angle doublet of five inches focus, which, by removing one combination, gives us a single lens of about 9 inches focus. It will thus be seen that from one standpoint, by simply altering our two lenses, it is possible to obtain five different renderings of the same sub- ject. This will be made clearer to the student in the chapter dealing with lenses. We only mention it here to show what