CompuServe Messages

Mark You may be confusing dots per inch of an imagesetter with the actual dots used in creating a photograph/half tone. An imagesetter may have the ability to produce a resolution of 1,200-2,700 dpi, but that is not the way a photo is reporduced. Generally in high quality magazines (and books) photographs (b&W half tones or process color) are produced with a line screen (essentially the same as dots per inch) of 133 or 155 lpi. But, the dots have a variable size (not a fixed size like the dots on a compuer screen) so they give the appearance of more dots than they actually have. Also the blending of colors creates the illusion of greater resolution. This can easily be seen by printing a tiff (or gif) image in black and white, then printing in the same resolution in color (try this on your under $700 desktop inkjet and see the difference). It is also obvious on your computer screen, look at a color photograph, then convert it to B&W and compare it. Maybe I am crazy, but due to the way the eye sees and handles color, I still think images on my Mac are more than adequate for identification purposes. An 8-bit image is good, a 16-bit is much better (and a 24-bit and above is probably unnecessary as most eyes can't really distinguish 1.6 mill colors as compared to 32,000). Lanny