Message-Id: <mailto:199506110145.SAA29292@listserv.ccit.arizona.edu> Date: Sat, 10 Jun 1995 12:41:26 +0000 From: Frank Dunn <mailto:frank@BRAZEN.DEMON.CO.UK> Subject: Re: Scanning B&W photonegatives ? To: Multiple recipients of list IMAGELIB
>Please let me know if you believe the following
>information is accurate.
snip...
>Scanning a black & white 4X5 negative at 400 dpi
>yields about a 2,601K tiff image.
>With no compression and scanning at 400 dpi you can
>store about 393 images per gigabyte.
Its a greyscale so thats 256 colour or 8 bits (1 byte depth).
(4"x400) x (5"x400) ó.2 million pixels or 3.2 Mb at 8 bit raw bitmap.
TIFF version 6 allows a number of compression schemes, RLE would get it
down to about 2.6 Mb lossless depending of picture content. IMHO JPEG on
greyscale isn't as efficient as JPEG on 24 bit or 32 bit colour. Your
mileage may vary.
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