Abraxas@pawl15.pawl.rpi.edu (03/24/90)
I scanned a photo in an art book the other day, at 300 dpi and 256 gray level, this 7x8 inch photo took nearly 4M in TIFF format. In an attempt to reduce the size, I have the following questions: 1 -- for b&w photos in the art book, what is an adequate dpi value. In some photo, I can actually see the small dots that are made up the picture, therefore, 300dpi is an over-kill. Am I right? 2 -- What is a reasonable gray-level to diginize a pic? Many researches shows that the human eye can reasonably distinquish 30-40 gray level, at most 128. What crateria can be used to determine the appropiate gray-level to be used? 3 -- Is there any other format more compact than TIFF? Can those experience 'scanners' out there give some general guideline on efficient digitization? Thankx Abraxas@pawl.rpi.edu