Any Plate Camera of the so-called cycle type may be used for enlarging by making use of the holding frame.
The negative in such cases is best secured in position by utilizing an old plate holder with the center septum and dark slides removed, insert the negative in the plate holder upside down and with the dull side toward the lens, placing the holder in the back of the camera in the usual manner.
If ground glass in the back of the camera inter cepts too much light it should be removed.
Unless the window you intend to use com mands an unobstruCted view of the horizon, a piece of heavy white cardboard about 15 inches long and 12 inches wide or larger should be placed just out side the window, at an angle of 45° to reflea the light from the sky. (See Fig. 2.) To ascertain if the reflejtor is in the proper position, place a sheet of ground glass over the opening in the holding frame. If properly placed the ground glass will be evenly illuminated. No harm will result if the sun shines on the ground glass and refleEtor, pro vided it strikes evenly ; if the light is too strong the lens can be stopped down.
The easel or copy-board for holding the bromide paper may be con stru6ted as shown in Figure 3 or it may be modified to suit individual needs or conditions.
In cases where the window is some distance from the floor, or the window surface is exceedingly large, the Kodak holding frame may be placed directly on the lower sill and the light excluded by covering the balance of the window as previously suggested.
The whole apparatus is so exceedingly simple that modifications to suit individual requirements can easily be made.
Care must be observed to keep the easel front exactly parallel with the negative.
The best negative for enlarging from is one not too dense or too weak but with good detail in the shadows and transparent in the high lights.
depends upon the focus of the lens and the distance of the easel or copy board from the negative.
Even when using the No. 4-A Folding Kodak with its lens of inch equivalent focus a six times enlargement will only require a distance of five feet from the lens to the bromide paper, so it will be seen that only a small space is necessary for all ordinary requirements.
Any lens that will make a good negative may be used for enlarging. The proper size (focal length) of the lens depends entirely upon the size of the negative to be enlarged from and not at all upon the size of the enlarge ment to be made.
The lens that made the negative will be suitable for enlarging from that negative. If the lens will cover the negative it will make an enlargement from it of any size. Any Kodak lens is suitable for enlarging from nega tives made with the Kodak to which it is fitted.
Having placed the negative in position, and taking care that the pack age of bromide paper is well protected, set the shutter for time and press the release to open same, an image more or less blurred will appear on the easel, now move the easel back and forth until the desired size of the enlarge ment is secured, then focus the image sharply by racking the lens back and forth.
The nearer the lens is placed to the negative the greater the size of the enlargement and the copy board will have to be moved back correspond ingly to obtain sharp focus.
Focus with the lens fully open, then stop down to at least stop .16. This not only insures good definition but by lengthening the time of expos ure permits greater control during exposure, affording time to shade or locally increase the exposure on any portion of the image.
After having obtained the desired size and correct focus close the ter and place the sheet of bromide paper in position on the easel or copy board. Before capping the lens or closing the shutter the correct position for placing the sheet of bromide paper should be marked on the copy board. A deep colored ray screen may be utilized as a lens cap, as the light coming through this screen will not affect the bromide paper for a few minutes, and the operator can by this means see just where to fasten the sheet of bromide. It is perhaps unnecessary to state that the coated or emulsion side of the paper should be out. (The coated side is slightly concave).