This section is from the book "Complete Self-Instructing Library Of Practical Photography", by J. B. Schriever. Also available from Amazon: Complete Self-Instructing Library Of Practical Photography.
The Ray Filter. The ray filter is quite essential in photographing blue flowers, but it is not necessary to use one of an extremely deep shade. Any ordinary light-colored ray filter may be employed - one that will increase the exposure about four times. A glass cell filled with a 1 per cent. solution of potassium bichromate will render very satisfactory results. (See Page 101.)
BLOSSOMS, CHEROKEE ROSE Study No. 29 - See Page 314 By Mrs. M. S. Gaines.
DAFFODILS Study No. 30 By S. I. Carpenter.
Speed Of Plate To Use. For indoor work a rapid plate is best, because when the relatively faint light is considered in connection with the small stop, or diaphragm, necessary to secure proper depth of focus, the exposure will sometimes require minutes.
Backgrounds. Backgrounds for use in photographing cut flowers need not be at all expensive. Excellent results can be secured by having at your command several pieces of cardboard 22 x 28 inches in size, or larger. These cards should be of various colors, but you will find that the mounting board, known as "carbon black," will answer for most purposes. Be sure that the surface of the cardboard is dull and not glossy.
Space Behind The Flowers. If the flowers are to be shown in a vase, and any of the table is visible in the photograph, the point where the table and background join will make a strongly marked line across the composition. This, as can be seen on reference to any flower picture where it is visible, is a mistake. It at once reveals the artificiality of the whole arrangement, by making it quite clear that the background, instead of being a mere suggestion, is purely artificial. If the picture is to be a success, this must be avoided in some manner. It will not do to carry one piece of paper down the background and along the table in a curve. The lighting will show the true nature of this at once, and the effect will be as bad, or even worse, than the other. The simplest plan is to have as great a width of table behind the flowers as possible, and place the background some distance beyond the table. By this means the table will blend into the background, and being out of focus, no harsh line will be visible. The perspective of the vase will show - however much the table is foreshortened - that there is a space behind the flowers, while the actual boundaries, being quite out of focus, will be softened down.
547. The only precaution that need be taken is to have the background far enough away from the flowers to prevent their shadows being in evidence. Shadows only reveal the presence of the background, and its temporary and artificial character, for by repeating the lines of the flowers - with variations - they add considerably to the difficulties of arrangement.