Bitmaps are also known as line art images. When you use a bitmap image, you are only using black and white pixels. Bitmaps are scans but can still be found in high resolution files. When you are working with vector art, you are using illustrator images that have been exported as EPS files. Illustrator also offers Raster formats which include grayscale rasters. Grayscale rasters are the easiest to work with because they only contain values of up to 255. They can be saved as illustrator file or they can be manipulated in photoshop and then can be implemented into inDesign files. Duotone rasters can be made in photoshop files. They can be saved in multiple formats which makes opening the files in other programs easier. The duotones can be made of two, three or four different colors but the two color duotone is the cheapest to print. A silhouette raster should be used when a cheaper print is necessary because it is the outline or just the black and white silhouette of the object you want to appear in your design. A full bleed raster means the images in the project should stretch the complete length of the available space. The average bleed of a design should be 0.125 of an inch. Four color rasters are CMYK images. They are made up of cyan, magenta, yellow and key and each layer of the color is printed over the first so that the colors can add up to the desired look of an image. Screen tint is used when shading and tinting are used in the process of line reproduction. Generally speaking, the majority of theses files are printed in CMYK form because the printing process is much cheaper. When the cost is a big influence on how the project is produced, CMYK is usually the color mode that is used. A reverse file is used when the opposite colors are used in the production process. The reversed image shows where opposite colors and usually makes the image more interesting.
Source:
McCue, C. Printing Production with Adobe Creative Suite Applications. 2009. Berkeley, Ca.
No comments:
Post a Comment