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Subject: Re: DPI and alignment. (was staples paper topic)

From: "Phil" <phil1960us@...>
Date: 2004-07-02

My point is that the driver has to convert it to the dot grid -
there are always conversions taking place. You will almost never
have an exact number of dots or exact dot alignment even if you start
with the English system. Its all arbitrary and the dot grid causes
fractional dots to be truncate or rounded up. You will always have
fractional dots to deal with - metric or English. I doubt seriously
that there is less precision (or more loss) when starting with metric.

There's a lot wrong with the English system but this isn't one of
them.

I'll stick to my 567 DPCM printer (er, 1440 DPI) with its tiny
fractional dot inaccuracies. I much prefer my 10 mil traces being 14
dots wide with a max of 0.07% error - probably better than the
accuracy of TT.

--- In Homebrew_PCBs@yahoogroups.com, Stefan Trethan
<stefan_trethan@g...> wrote:
> On Fri, 02 Jul 2004 18:24:52 -0000, Phil <phil1960us@y...> wrote:
>
> > I'm not so sure that a 7 mil trace is going to come out that well
on
> > a 300 dpi device. that is basically 2 dots wide (2.1 to be exact
but
> > it doesn't do partial dots). that isn't very much toner. 10 mils
is 3
> > dots and that's still kind of light.
> >
>
> yes, correct, IF you draw the lines on a grid in mil.
> if yo have metric grid (e.g. metric spaced flatpack)
> the driver must convert it, and will make alternating two or three
dot
> traces,
> same with space between traces.
> Things get ugly and irregular.
>
> both 2 dot and 3 dot traces come out well, it doesn't do one dot
but i
> think it does one-dot with very small fonts, which still come out
well.
>
>
> st