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RESTATED question Re: [OCLUG-Tech] producing distributable files from Graphic material. old schematic diagrams.

  • Subject: RESTATED question Re: [OCLUG-Tech] producing distributable files from Graphic material. old schematic diagrams.
  • From: "Ima Gnuber" <ima [ dot ] gnuber [ at ] gmail [ dot ] com>
  • Date: Mon, 12 Nov 2007 21:31:49 -0500
I've been watching this with some interest. I think you are thinking
of this in the wrong way as 44MB seems a somewhat excessive file size.

Think in terms of printing a photograph (my usual frame of reference).

Scaling the provided sample image from a 72 ppi gif to 1.5 inches
width = 1650ppi.

A good photo image could be 150 to 300 ppi.

If you want to scan at the higher density then the GIMP becomes your
friend for manipulating and improving the image AND file size.

sample image converted using the GIMP - converted to jpg to reduce file size

original sample file size = 2.8MB

150 × 150 ppi 38.10 × 21.34 millimeters = 26.9 KB greyscale jpg

Providing a larger image at higher pixel density:
300 x 300 ppi 76.28 × 42.76 millimeters = 346 KB greyscale jpg
300 × 300 ppi 76.28 × 42.76 millimeters = 348 KB rgb jpg

You could also increase brightness by 20 and contrast by 15.

Hope this helps.

-Ima