As regards lithographic processes for reproduction in one colour the cost varies with the nature of the work. If an artist be commissioned to make an autolithograph, the fee would be agreed upon beforehand. Photolithography and collotype, on the other hand, are processes which do not require the hand of an artist, and these methods of reproduction are relatively inexpensive. The price quoted by the lithographer or collotyper is for printing so many copies, hence the relative cost per copy depends upon the run and on the quality of the paper used. Lithography is cheaper than collotype; but if several illustrations are sent at the same time to be reproduced by collotype, the cost for each would be less than if sent separately.
In chromolithography a separate stone is necessary for each colour, hence the cost depends upon the number of stones used, and as several may be necessary to obtain a first-rate reproduction, it is obvious that the process may prove very expensive.
Turning to photomechanical processes, the prices vary according to the grade of work required—the best possible, good, and, lastly, cheap work. By best possible is meant the best that can be made under existing conditions, the price being immaterial; in good work the cost will be a limiting but not a preponderating factor, hence the work will be open to criticism; finally, in cheap work, the price is all important, so that the result is a block or a plate which will print well but which must not be criticized as regards its being a faithful reproduction of the original.
It is obvious that in the last two cases the quality of the work will depend upon the agreed price, whilst in the first case the cost will depend on the amount of time and skill required.
It is obvious, therefore, that a comparison of cost cannot be made between these grades; it is, however, possible to draw up a scale of relative cost of the processes under consideration for work of the same grade. In the table given below, A represents the best possible work, B indicates good work, and C stands for cheap work. Since the line block is the least expensive it is taken as the unit of price; that is to say, if a line block costs 3d. per square inch the cost of half tone, three colour half tone and photogravure would be 7¼d., 3s., and 1s. 2½d. respectively.
| A | B | C | |
| Line | 1 | 1 | 1 |
| Half tone and swelled gelatine | 2½ | 2¼ | 2 |
| Half tone three colour (three plates required) | 9 | 12 | 10½ |
| Photogravure | 4½ | 4¾ | 5 |
It must not be thought that if the area of a block is 3 square inches, the cost will, therefore, be 9d. There is, for obvious reasons, a minimum size at which the block or plate is charged although it may be smaller. These minima vary; in general terms they may be taken as 12 inches for line, half tone and swelled gelatine blocks, and 20 inches for half tone three colour blocks and photogravure plates. The measurements are the areas of the etched surface, the actual plate or block may be larger, but for this margin no charge is made.
With regard to cost of printing, nothing need be said about blocks which are set up with the type, namely line, swelled gelatine and coarse half tone blocks. The price of printing fine half tones and three colour blocks depends upon the quality of the paper used and the fineness of the work. Photogravure plates must be hand printed (photogravure printing on rotary machines is not considered here), and skill is required; for ordinary printing on good plate paper the price would be 10s. to 12s. 6d. per hundred copies, whilst for India printing the cost would be about 25s. for the same number.
LITERATURE
Barnes: Illustrating Botanical Papers, Botanical Gazette, Vol. 43, 1907.