15 Apr
2009
15 Apr
'09
12:53 p.m.
Jan-Benedict Glaw wrote:
On Tue, 2009-04-14 10:52:00 -0500, Jules Richardson
<jules.richardson99 at gmail.com> wrote:
you are confusing linear pixel density with areal pixel density.
the 11"x13" fitting in 1"x1.5" implies a 11:1 scaling in density, so
300
dpi would be 3300 dpi. still very high for typical consumer grade
scanners. I believe 2400 dpi actual (not interpolated) is available on
decent models, though.
The DEC ones I've seen are extremely high
resolution - from memory,
something like 11 x 13 A4 pages on a fiche around 1" x 1.5".
If this is right, then there's a scale factor of about 1:90 to 1:100
involved. That should tell everybody why even a good consumer-grade
scanner will not do the job. To get the equivalent of a 300dpi scan,
you'd need to have about 30000dpi. Nothing any el-cheapo scanner could
handle. (Let alone the problem of getting the sheet properly into the
light's focus.)