rrw@naucse.UUCP (Robert Wier) (05/04/89)
Has anyone out there using an Apple Scanner with a LaserPrinter found the "magic" number for doing enlargements without generating objectionable dithering aliasing. If you scan a picture at 300 dpi, and print it at, say, 200% you get WEIRD patterns because of the overlapping dither patterns. Through trial and error (mostly error) I have found that 175% works pretty well. I would assume that this could be calculated if you knew what AppleScan was doing with it's dithering technique. However, as of yet, I havn't been able to figure out why 175% works pretty well, while 200% is unusable. I assume that the "magic" enlargement numbers would be somthing where a common factor is the 300 dpi scan resolution, and the (4x4? 5x5? 8x8?) dithering algorithm. If you can help, please post here or E-Mail to me and I will post a summary to the net. THANKS! - Bob Wier College of Engineering Flagstaff, Arizona Northern Arizona University ...arizona!naucse!rrw | BITNET: WIER@NAUVAX | *usual disclaimers*